EXTERNAL USER INTERFACE FOR HEAD WORN COMPUTING

[0001] This application claims the benefit of priority to and is a continuation-in-part of the following U.S. patent applications:

[0002] U.S. non-provisional application Ser. No. 14/472,145 entitled EXTERNAL USER INTERFACE FOR HEAD WORN COMPUTING, filed Aug. 28, 2014. U.S. non-provisional application Ser. No. 14/472,145 is a continuation-in-part of U.S. non-provisional application Ser. No. 14/462,415 entitled EXTERNAL USER INTERFACE FOR HEAD WORN COMPUTING, filed Aug. 18, 2014. U.S. non-provisional application Ser. No. 14/462,415 is a continuation-in-part of U.S. application Ser. No. 14/337,346 entitled EXTERNAL USER INTERFACE HEAD WORN COMPUTING, filed Jul. 22, 2014.

[0003] This application is also a continuation-in-part of U.S. non-provisional application Ser. No. 14/462,415 entitled EXTERNAL USER INTERFACE FOR HEAD WORN COMPUTING, filed Aug. 18, 2014.

[0004] This application is also a continuation-in-part of U.S. non-provisional application Ser. No. 14/337,346 entitled EXTERNAL USER INTERACE FOR HEAD WORN COMPUTING, filed Jul. 22, 2014.

[0005] 1. Field of the Invention

[0006] This invention relates to head worn computing. More particularly, this invention relates to external user interfaces related to head worn computing.

[0007] 2. Description of Related Art

[0008] Wearable computing systems have been developed and are beginning to be commercialized. Many problems persist in the wearable computing field that need to be resolved to make them meet the demands of the market.

[0009] Aspects of the present invention relate to the systems and methods of predicting the interaction with virtual user interfaces presented in connection with head-worn see-through computer displays.

[0010] These and other systems, methods, objects, features, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of the preferred embodiment and the drawings. All documents mentioned herein are hereby incorporated in their entirety by reference.

[0021] While the invention has been described in connection with certain preferred embodiments, other embodiments would be understood by one of ordinary skill in the art and are encompassed herein.

[0022] Aspects of the present invention relate to head-worn computing (“HWC”) systems. HWC involves, in some instances, a system that mimics the appearance of head-worn glasses or sunglasses. The glasses may be a fully developed computing platform, such as including computer displays presented in each of the lenses of the glasses to the eyes of the user. In embodiments, the lenses and displays may be configured to allow a person wearing the glasses to see the environment through the lenses while also seeing, simultaneously, digital imagery, which forms an overlaid image that is perceived by the person as a digitally augmented image of the environment, or augmented reality (“AR”).

[0023] HWC involves more than just placing a computing system on a person's head. The system may need to be designed as a lightweight, compact and fully functional computer display, such as wherein the computer display includes a high resolution digital display that provides a high level of emersion comprised of the displayed digital content and the see-through view of the environmental surroundings. User interfaces and control systems suited to the HWC device may be required that are unlike those used for a more conventional computer such as a laptop. For the HWC and associated systems to be most effective, the glasses may be equipped with sensors to determine environmental conditions, geographic location, relative positioning to other points of interest, objects identified by imaging and movement by the user or other users in a connected group, and the like. The HWC may then change the mode of operation to match the conditions, location, positioning, movements, and the like, in a method generally referred to as a contextually aware HWC. The glasses also may need to be connected, wirelessly or otherwise, to other systems either locally or through a network. Controlling the glasses may be achieved through the use of an external device, automatically through contextually gathered information, through user gestures captured by the glasses sensors, and the like. Each technique may be further refined depending on the software application being used in the glasses. The glasses may further be used to control or coordinate with external devices that are associated with the glasses.

[0024] Referring to FIG. 1, an overview of the HWC system 100 is presented. As shown, the HWC system 100 comprises a HWC 102, which in this instance is configured as glasses to be worn on the head with sensors such that the HWC 102 is aware of the objects and conditions in the environment 114. In this instance, the HWC 102 also receives and interprets control inputs such as gestures and movements 116. The HWC 102 may communicate with external user interfaces 104. The external user interfaces 104 may provide a physical user interface to take control instructions from a user of the HWC 102 and the external user interfaces 104 and the HWC 102 may communicate bi-directionally to affect the user's command and provide feedback to the external device 108. The HWC 102 may also communicate bi-directionally with externally controlled or coordinated local devices 108. For example, an external user interface 104 may be used in connection with the HWC 102 to control an externally controlled or coordinated local device 108. The externally controlled or coordinated local device 108 may provide feedback to the HWC 102 and a customized GUI may be presented in the HWC 102 based on the type of device or specifically identified device 108. The HWC 102 may also interact with remote devices and information sources 112 through a network connection 110. Again, the external user interface 104 may be used in connection with the HWC 102 to control or otherwise interact with any of the remote devices 108 and information sources 112 in a similar way as when the external user interfaces 104 are used to control or otherwise interact with the externally controlled or coordinated local devices 108. Similarly, HWC 102 may interpret gestures 116 (e.g captured from forward, downward, upward, rearward facing sensors such as camera(s), range finders, IR sensors, etc.) or environmental conditions sensed in the environment 114 to control either local or remote devices 108 or 112.

[0025] We will now describe each of the main elements depicted on FIG. 1 in more detail; however, these descriptions are intended to provide general guidance and should not be construed as limiting. Additional description of each element may also be further described herein.

[0026] The HWC 102 is a computing platform intended to be worn on a person's head. The HWC 102 may take many different forms to fit many different functional requirements. In some situations, the HWC 102 will be designed in the form of conventional glasses. The glasses may or may not have active computer graphics displays. In situations where the HWC 102 has integrated computer displays the displays may be configured as see-through displays such that the digital imagery can be overlaid with respect to the user's view of the environment 114. There are a number of see-through optical designs that may be used, including ones that have a reflective display (e.g. LCoS, DLP), emissive displays (e.g. OLED, LED), hologram, TIR waveguides, and the like. In addition, the optical configuration may be monocular or binocular. It may also include vision corrective optical components. In embodiments, the optics may be packaged as contact lenses. In other embodiments, the HWC 102 may be in the form of a helmet with a see-through shield, sunglasses, safety glasses, goggles, a mask, fire helmet with see-through shield, police helmet with see through shield, military helmet with see-through shield, utility form customized to a certain work task (e.g. inventory control, logistics, repair, maintenance, etc.), and the like.

[0027] The HWC 102 may also have a number of integrated computing facilities, such as an integrated processor, integrated power management, communication structures (e.g. cell net, WiFi, Bluetooth, local area connections, mesh connections, remote connections (e.g. client server, etc.)), and the like. The HWC 102 may also have a number of positional awareness sensors, such as GPS, electronic compass, altimeter, tilt sensor, IMU, and the like. It may also have other sensors such as a camera, rangefinder, hyper-spectral camera, Geiger counter, microphone, spectral illumination detector, temperature sensor, chemical sensor, biologic sensor, moisture sensor, ultrasonic sensor, and the like.

[0028] The HWC 102 may also have integrated control technologies. The integrated control technologies may be contextual based control, passive control, active control, user control, and the like. For example, the HWC 102 may have an integrated sensor (e.g. camera) that captures user hand or body gestures 116 such that the integrated processing system can interpret the gestures and generate control commands for the HWC 102. In another example, the HWC 102 may have sensors that detect movement (e.g. a nod, head shake, and the like) including accelerometers, gyros and other inertial measurements, where the integrated processor may interpret the movement and generate a control command in response. The HWC 102 may also automatically control itself based on measured or perceived environmental conditions. For example, if it is bright in the environment the HWC 102 may increase the brightness or contrast of the displayed image. In embodiments, the integrated control technologies may be mounted on the HWC 102 such that a user can interact with it directly. For example, the HWC 102 may have a button(s), touch capacitive interface, and the like.

[0029] As described herein, the HWC 102 may be in communication with external user interfaces 104. The external user interfaces may come in many different forms. For example, a cell phone screen may be adapted to take user input for control of an aspect of the HWC 102. The external user interface may be a dedicated UI, such as a keyboard, touch surface, button(s), joy stick, and the like. In embodiments, the external controller may be integrated into another device such as a ring, watch, bike, car, and the like. In each case, the external user interface 104 may include sensors (e.g. IMU, accelerometers, compass, altimeter, and the like) to provide additional input for controlling the HWD 104.

[0030] As described herein, the HWC 102 may control or coordinate with other local devices 108. The external devices 108 may be an audio device, visual device, vehicle, cell phone, computer, and the like. For instance, the local external device 108 may be another HWC 102, where information may then be exchanged between the separate HWCs 108.

[0031] Similar to the way the HWC 102 may control or coordinate with local devices 106, the HWC 102 may control or coordinate with remote devices 112, such as the HWC 102 communicating with the remote devices 112 through a network 110. Again, the form of the remote device 112 may have many forms. Included in these forms is another HWC 102. For example, each HWC 102 may communicate its GPS position such that all the HWCs 102 know where all of HWC 102 are located.

[0032] Referring to FIG. 2, we now turn to describe a particular external user interface 104, referred to generally as a pen 200. The pen 200 is a specially designed external user interface 104 and can operate as a user interface, such as to many different styles of HWC 102. The pen 200 generally follows the form of a conventional pen, which is a familiar user handled device and creates an intuitive physical interface for many of the operations to be carried out in the HWC system 100. The pen 200 may be one of several user interfaces 104 used in connection with controlling operations within the HWC system 100. For example, the HWC 102 may watch for and interpret hand gestures 116 as control signals, where the pen 200 may also be used as a user interface with the same HWC 102. Similarly, a remote keyboard may be used as an external user interface 104 in concert with the pen 200. The combination of user interfaces or the use of just one control system generally depends on the operation(s) being executed in the HWC's system 100.

[0033] While the pen 200 may follow the general form of a conventional pen, it contains numerous technologies that enable it to function as an external user interface 104. FIG. 2 illustrate technologies comprised in the pen 200. As can be seen, the pen 200 may include a camera 208, which is arranged to view through lens 202. The camera may then be focused, such as through lens 202, to image a surface upon which a user is writing or making other movements to interact with the HWC 102. There are situations where the pen 200 will also have an ink, graphite, or other system such that what is being written can be seen on the writing surface. There are other situations where the pen 200 does not have such a physical writing system so there is no deposit on the writing surface, where the pen would only be communicating data or commands to the HWC 102. The lens configuration is described in greater detail herein. The function of the camera is to capture information from an unstructured writing surface such that pen strokes can be interpreted as intended by the user. To assist in the predication of the intended stroke path, the pen 200 may include a sensor, such as an IMU 212. Of course, the IMU could be included in the pen 200 in its separate parts (e.g. gyro, accelerometer, etc.) or an IMU could be included as a single unit. In this instance, the IMU 212 is used to measure and predict the motion of the pen 200. In turn, the integrated microprocessor 210 would take the IMU information and camera information as inputs and process the information to form a prediction of the pen tip movement.

[0034] The pen 200 may also include a pressure monitoring system 204, such as to measure the pressure exerted on the lens 202. As will be described in greater herein, the pressure measurement can be used to predict the user's intention for changing the weight of a line, type of a line, type of brush, click, double click, and the like. In embodiments, the pressure sensor may be constructed using any force or pressure measurement sensor located behind the lens 202, including for example, a resistive sensor, a current sensor, a capacitive sensor, a voltage sensor such as a piezoelectric sensor, and the like.

[0035] The pen 200 may also include a communications module 218, such as for bi-directional communication with the HWC 102. In embodiments, the communications module 218 may be a short distance communication module (e.g. Bluetooth). The communications module 218 may be security matched to the HWC 102. The communications module 218 may be arranged to communicate data and commands to and from the microprocessor 210 of the pen 200. The microprocessor 210 may be programmed to interpret data generated from the camera 208, IMU 212, and pressure sensor 204, and the like, and then pass a command onto the HWC 102 through the communications module 218, for example. In another embodiment, the data collected from any of the input sources (e.g. camera 108, IMU 212, pressure sensor 104) by the microprocessor may be communicated by the communication module 218 to the HWC 102, and the HWC 102 may perform data processing and prediction of the user's intention when using the pen 200. In yet another embodiment, the data may be further passed on through a network 110 to a remote device 112, such as a server, for the data processing and prediction. The commands may then be communicated back to the HWC 102 for execution (e.g. display writing in the glasses display, make a selection within the UI of the glasses display, control a remote external device 112, control a local external device 108), and the like. The pen may also include memory 214 for long or short term uses.

[0036] The pen 200 may also include a number of physical user interfaces, such as quick launch buttons 222, a touch sensor 220, and the like. The quick launch buttons 222 may be adapted to provide the user with a fast way of jumping to a software application in the HWC system 100. For example, the user may be a frequent user of communication software packages (e.g. email, text, Twitter, Instagram, Facebook, Google+, and the like), and the user may program a quick launch button 222 to command the HWC 102 to launch an application. The pen 200 may be provided with several quick launch buttons 222, which may be user programmable or factory programmable. The quick launch button 222 may be programmed to perform an operation. For example, one of the buttons may be programmed to clear the digital display of the HWC 102. This would create a fast way for the user to clear the screens on the HWC 102 for any reason, such as for example to better view the environment. The quick launch button functionality will be discussed in further detail below. The touch sensor 220 may be used to take gesture style input from the user. For example, the user may be able to take a single finger and run it across the touch sensor 220 to affect a page scroll.

[0037] The pen 200 may also include a laser pointer 224. The laser pointer 224 may be coordinated with the IMU 212 to coordinate gestures and laser pointing. For example, a user may use the laser 224 in a presentation to help with guiding the audience with the interpretation of graphics and the IMU 212 may, either simultaneously or when the laser 224 is off, interpret the user's gestures as commands or data input.

[0038] FIGS. 3A-C illustrate several embodiments of lens and camera arrangements 300 for the pen 200. One aspect relates to maintaining a constant distance between the camera and the writing surface to enable the writing surface to be kept in focus for better tracking of movements of the pen 200 over the writing surface. Another aspect relates to maintaining an angled surface following the circumference of the writing tip of the pen 200 such that the pen 200 can be rolled or partially rolled in the user's hand to create the feel and freedom of a conventional writing instrument.

[0039] FIG. 3A illustrates an embodiment of the writing lens end of the pen 200. The configuration includes a ball lens 304, a camera or image capture surface 302, and a domed cover lens 308. In this arrangement, the camera views the writing surface through the ball lens 304 and dome cover lens 308. The ball lens 304 causes the camera to focus such that the camera views the writing surface when the pen 200 is held in the hand in a natural writing position, such as with the pen 200 in contact with a writing surface. In embodiments, the ball lens 304 should be separated from the writing surface to obtain the highest resolution of the writing surface at the camera 302. In embodiments, the ball lens 304 is separated by approximately 1 to 3 mm. In this configuration, the domed cover lens 308 provides a surface that can keep the ball lens 304 separated from the writing surface at a constant distance, such as substantially independent of the angle used to write on the writing surface. For instance, in embodiments the field of view of the camera in this arrangement would be approximately 60 degrees.

[0040] The domed cover lens, or other lens 308 used to physically interact with the writing surface, will be transparent or transmissive within the active bandwidth of the camera 302. In embodiments, the domed cover lens 308 may be spherical or other shape and comprised of glass, plastic, sapphire, diamond, and the like. In other embodiments where low resolution imaging of the surface is acceptable. The pen 200 can omit the domed cover lens 308 and the ball lens 304 can be in direct contact with the surface.

[0041] FIG. 3B illustrates another structure where the construction is somewhat similar to that described in connection with FIG. 3A; however this embodiment does not use a dome cover lens 308, but instead uses a spacer 310 to maintain a predictable distance between the ball lens 304 and the writing surface, wherein the spacer may be spherical, cylindrical, tubular or other shape that provides spacing while allowing for an image to be obtained by the camera 302 through the lens 304. In a preferred embodiment, the spacer 310 is transparent. In addition, while the spacer 310 is shown as spherical, other shapes such a an oval, doughnut shape, half sphere, cone, cylinder or other form may be used.

[0042] FIG. 3C illustrates yet another embodiment, where the structure includes a post 314, such as running through the center of the lensed end of the pen 200. The post 314 may be an ink deposition system (e.g. ink cartridge), graphite deposition system (e.g. graphite holder), or a dummy post whose purpose is mainly only that of alignment. The selection of the post type is dependent on the pen's use. For instance, in the event the user wants to use the pen 200 as a conventional ink depositing pen as well as a fully functional external user interface 104, the ink system post would be the best selection. If there is no need for the ‘writing’ to be visible on the writing surface, the selection would be the dummy post. The embodiment of FIG. 3C includes camera(s) 302 and an associated lens 312, where the camera 302 and lens 312 are positioned to capture the writing surface without substantial interference from the post 314. In embodiments, the pen 200 may include multiple cameras 302 and lenses 312 such that more or all of the circumference of the tip 314 can be used as an input system. In an embodiment, the pen 200 includes a contoured grip that keeps the pen aligned in the user's hand so that the camera 302 and lens 312 remains pointed at the surface.

[0043] Another aspect of the pen 200 relates to sensing the force applied by the user to the writing surface with the pen 200. The force measurement may be used in a number of ways. For example, the force measurement may be used as a discrete value, or discontinuous event tracking, and compared against a threshold in a process to determine a user's intent. The user may want the force interpreted as a ‘click’ in the selection of an object, for instance. The user may intend multiple force exertions interpreted as multiple clicks. There may be times when the user holds the pen 200 in a certain position or holds a certain portion of the pen 200 (e.g. a button or touch pad) while clicking to affect a certain operation (e.g. a ‘right click’). In embodiments, the force measurement may be used to track force and force trends. The force trends may be tracked and compared to threshold limits, for example. There may be one such threshold limit, multiple limits, groups of related limits, and the like. For example, when the force measurement indicates a fairly constant force that generally falls within a range of related threshold values, the microprocessor 210 may interpret the force trend as an indication that the user desires to maintain the current writing style, writing tip type, line weight, brush type, and the like. In the event that the force trend appears to have gone outside of a set of threshold values intentionally, the microprocessor may interpret the action as an indication that the user wants to change the current writing style, writing tip type, line weight, brush type, and the like. Once the microprocessor has made a determination of the user's intent, a change in the current writing style, writing tip type, line weight, brush type, and the like. may be executed. In embodiments, the change may be noted to the user (e.g. in a display of the HWC 102), and the user may be presented with an opportunity to accept the change.

[0044] FIG. 4A illustrates an embodiment of a force sensing surface tip 400 of a pen 200. The force sensing surface tip 400 comprises a surface connection tip 402 (e.g. a lens as described herein elsewhere) in connection with a force or pressure monitoring system 204. As a user uses the pen 200 to write on a surface or simulate writing on a surface the force monitoring system 204 measures the force or pressure the user applies to the writing surface and the force monitoring system communicates data to the microprocessor 210 for processing. In this configuration, the microprocessor 210 receives force data from the force monitoring system 204 and processes the data to make predictions of the user's intent in applying the particular force that is currently being applied. In embodiments, the processing may be provided at a location other than on the pen (e.g. at a server in the HWC system 100, on the HWC 102). For clarity, when reference is made herein to processing information on the microprocessor 210, the processing of information contemplates processing the information at a location other than on the pen. The microprocessor 210 may be programmed with force threshold(s), force signature(s), force signature library and/or other characteristics intended to guide an inference program in determining the user's intentions based on the measured force or pressure. The microprocessor 210 may be further programmed to make inferences from the force measurements as to whether the user has attempted to initiate a discrete action (e.g. a user interface selection ‘click’) or is performing a constant action (e.g. writing within a particular writing style). The inferencing process is important as it causes the pen 200 to act as an intuitive external user interface 104.

[0045] FIG. 4B illustrates a force 408 versus time 410 trend chart with a single threshold 418. The threshold 418 may be set at a level that indicates a discrete force exertion indicative of a user's desire to cause an action (e.g. select an object in a GUI). Event 412, for example, may be interpreted as a click or selection command because the force quickly increased from below the threshold 418 to above the threshold 418. The event 414 may be interpreted as a double click because the force quickly increased above the threshold 418, decreased below the threshold 418 and then essentially repeated quickly. The user may also cause the force to go above the threshold 418 and hold for a period indicating that the user is intending to select an object in the GUI (e.g. a GUI presented in the display of the HWC 102) and ‘hold’ for a further operation (e.g. moving the object).

[0046] While a threshold value may be used to assist in the interpretation of the user's intention, a signature force event trend may also be used. The threshold and signature may be used in combination or either method may be used alone. For example, a single-click signature may be represented by a certain force trend signature or set of signatures. The single-click signature(s) may require that the trend meet a criteria of a rise time between x any y values, a hold time of between a and b values and a fall time of between c and d values, for example. Signatures may be stored for a variety of functions such as click, double click, right click, hold, move, etc. The microprocessor 210 may compare the real-time force or pressure tracking against the signatures from a signature library to make a decision and issue a command to the software application executing in the GUI.

[0047] FIG. 4C illustrates a force 408 versus time 410 trend chart with multiple thresholds 418. By way of example, the force trend is plotted on the chart with several pen force or pressure events. As noted, there are both presumably intentional events 420 and presumably non-intentional events 422. The two thresholds 418 of FIG. 4C create three zones of force: a lower, middle and higher range. The beginning of the trend indicates that the user is placing a lower zone amount of force. This may mean that the user is writing with a given line weight and does not intend to change the weight, the user is writing. Then the trend shows a significant increase 420 in force into the middle force range. This force change appears, from the trend to have been sudden and thereafter it is sustained. The microprocessor 210 may interpret this as an intentional change and as a result change the operation in accordance with preset rules (e.g. change line width, increase line weight, etc.). The trend then continues with a second apparently intentional event 420 into the higher-force range. During the performance in the higher-force range, the force dips below the upper threshold 418. This may indicate an unintentional force change and the microprocessor may detect the change in range however not affect a change in the operations being coordinated by the pen 200. As indicated above, the trend analysis may be done with thresholds and/or signatures.

[0048] Generally, in the present disclosure, instrument stroke parameter changes may be referred to as a change in line type, line weight, tip type, brush type, brush width, brush pressure, color, and other forms of writing, coloring, painting, and the like.

[0049] Another aspect of the pen 200 relates to selecting an operating mode for the pen 200 dependent on contextual information and/or selection interface(s). The pen 200 may have several operating modes. For instance, the pen 200 may have a writing mode where the user interface(s) of the pen 200 (e.g. the writing surface end, quick launch buttons 222, touch sensor 220, motion based gesture, and the like) is optimized or selected for tasks associated with writing. As another example, the pen 200 may have a wand mode where the user interface(s) of the pen is optimized or selected for tasks associated with software or device control (e.g. the HWC 102, external local device, remote device 112, and the like). The pen 200, by way of another example, may have a presentation mode where the user interface(s) is optimized or selected to assist a user with giving a presentation (e.g. pointing with the laser pointer 224 while using the button(s) 222 and/or gestures to control the presentation or applications relating to the presentation). The pen may, for example, have a mode that is optimized or selected for a particular device that a user is attempting to control. The pen 200 may have a number of other modes and an aspect of the present invention relates to selecting such modes.

[0050] FIG. 5A illustrates an automatic user interface(s) mode selection based on contextual information. The microprocessor 210 may be programmed with IMU thresholds 514 and 512. The thresholds 514 and 512 may be used as indications of upper and lower bounds of an angle 504 and 502 of the pen 200 for certain expected positions during certain predicted modes. When the microprocessor 210 determines that the pen 200 is being held or otherwise positioned within angles 502 corresponding to writing thresholds 514, for example, the microprocessor 210 may then institute a writing mode for the pen's user interfaces. Similarly, if the microprocessor 210 determines (e.g. through the IMU 212) that the pen is being held at an angle 504 that falls between the predetermined wand thresholds 512, the microprocessor may institute a wand mode for the pen's user interface. Both of these examples may be referred to as context based user interface mode selection as the mode selection is based on contextual information (e.g. position) collected automatically and then used through an automatic evaluation process to automatically select the pen's user interface(s) mode.

[0051] As with other examples presented herein, the microprocessor 210 may monitor the contextual trend (e.g. the angle of the pen over time) in an effort to decide whether to stay in a mode or change modes. For example, through signatures, thresholds, trend analysis, and the like, the microprocessor may determine that a change is an unintentional change and therefore no user interface mode change is desired.

[0052] FIG. 5B illustrates an automatic user interface(s) mode selection based on contextual information. In this example, the pen 200 is monitoring (e.g. through its microprocessor) whether or not the camera at the writing surface end 208 is imaging a writing surface in close proximity to the writing surface end of the pen 200. If the pen 200 determines that a writing surface is within a predetermined relatively short distance, the pen 200 may decide that a writing surface is present 502 and the pen may go into a writing mode user inteface(s) mode. In the event that the pen 200 does not detect a relatively close writing surface 504, the pen may predict that the pen is not currently being used to as a writing instrument and the pen may go into a non-writing user interface(s) mode.

[0053] FIG. 5C illustrates a manual user interface(s) mode selection. The user interface(s) mode may be selected based on a twist of a section 508 of the pen 200 housing, clicking an end button 510, pressing a quick launch button 222, interacting with touch sensor 220, detecting a predetermined action at the pressure monitoring system (e.g. a click), detecting a gesture (e.g. detected by the IMU), etc. The manual mode selection may involve selecting an item in a GUI associated with the pen 200 (e.g. an image presented in the display of HWC 102).

[0054] In embodiments, a confirmation selection may be presented to the user in the event a mode is going to change. The presentation may be physical (e.g. a vibration in the pen 200), through a GUI, through a light indicator, etc.

[0055] FIG. 6 illustrates a couple pen use-scenarios 600 and 601. There are many use scenarios and we have presented a couple in connection with FIG. 6 as a way of illustrating use scenarios to further the understanding of the reader. As such, the use-scenarios should be considered illustrative and non-limiting.

[0056] Use scenario 600 is a writing scenario where the pen 200 is used as a writing instrument. In this example, quick launch button 122A is pressed to launch a note application 610 in the GUI 608 of the HWC 102 display 604. Once the quick launch button 122A is pressed, the HWC 102 launches the note program 610 and puts the pen into a writing mode. The user uses the pen 200 to scribe symbols 602 on a writing surface, the pen records the scribing and transmits the scribing to the HWC 102 where symbols representing the scribing are displayed 612 within the note application 610.

[0057] Use scenario 601 is a gesture scenario where the pen 200 is used as a gesture capture and command device. In this example, the quick launch button 122B is activated and the pen 200 activates a wand mode such that an application launched on the HWC 102 can be controlled. Here, the user sees an application chooser 618 in the display(s) of the HWC 102 where different software applications can be chosen by the user. The user gestures (e.g. swipes, spins, turns, etc.) with the pen to cause the application chooser 618 to move from application to application. Once the correct application is identified (e.g. highlighted) in the chooser 618, the user may gesture or click or otherwise interact with the pen 200 such that the identified application is selected and launched. Once an application is launched, the wand mode may be used to scroll, rotate, change applications, select items, initiate processes, and the like, for example.

[0058] In an embodiment, the quick launch button 122A may be activated and the HWC 102 may launch an application chooser presenting to the user a set of applications. For example, the quick launch button may launch a chooser to show all communication programs (e.g. SMS, Twitter, Instagram, Facebook, email, etc.) available for selection such that the user can select the program the user wants and then go into a writing mode. By way of further example, the launcher may bring up selections for various other groups that are related or categorized as generally being selected at a given time (e.g. Microsoft Office products, communication products, productivity products, note products, organizational products, and the like)

[0059] FIG. 7 illustrates yet another embodiment of the present invention. FIG. 700 illustrates a watchband clip on controller 700. The watchband clip on controller may be a controller used to control the HWC 102 or devices in the HWC system 100. The watchband clip on controller 700 has a fastener 718 (e.g. rotatable clip) that is mechanically adapted to attach to a watchband, as illustrated at 704.

[0060] The watchband controller 700 may have quick launch interfaces 708 (e.g. to launch applications and choosers as described herein), a touch pad 714 (e.g. to be used as a touch style mouse for GUI control in a HWC 102 display) and a display 712. The clip 718 may be adapted to fit a wide range of watchbands so it can be used in connection with a watch that is independently selected for its function. The clip, in embodiments, is rotatable such that a user can position it in a desirable manner. In embodiments the clip may be a flexible strap. In embodiments, the flexible strap may be adapted to be stretched to attach to a hand, wrist, finger, device, weapon, and the like.

[0061] In embodiments, the watchband controller may be configured as a removable and replacable watchband. For example, the controller may be incorporated into a band with a certain width, segment spacing's, etc. such that the watchband, with its incorporated controller, can be attached to a watch body. The attachment, in embodiments, may be mechanically adapted to attach with a pin upon which the watchband rotates. In embodiments, the watchband controller may be electrically connected to the watch and/or watch body such that the watch, watch body and/or the watchband controller can communicate data between them.

[0062] The watchband controller may have 3-axis motion monitoring (e.g. through an IMU, accelerometers, magnetometers, gyroscopes, etc.) to capture user motion. The user motion may then be interpreted for gesture control.

[0063] In embodiments, the watchband controller may comprise fitness sensors and a fitness computer. The sensors may track heart rate, calories burned, strides, distance covered, and the like. The data may then be compared against performance goals and/or standards for user feedback.

[0064] Another aspect of the present invention relates to tracking pen movements with the assistance of a camera and displayed content in a HWC 102. In embodiments, content is presented in a see-through display of a head-worn computer to provide a virtual guide for the wearer who wants to make motions with a pen, finger, or other interface and have the motions interpreted for pattern recognition. As described in connection with pen embodiments disclosed herein elsewhere, an IMU or pen-tip camera may be used to monitor the motion of a pen in order to predict what patterns are being drawn. The IMU and/or pen tip camera may suffer from electronic or optical drift and the drift may cause inaccuracies in the pattern prediction. In embodiments, to augment the IMU and/or pen tip camera motion predictions the virtual guide is provided to compensate for the drift. The pen motions may be captured by a camera on-board the HWC 102 while the wearer is writing with the guidance of the virtual line. Knowing that the wearer is using the virtual line as a guide, the relative position between the pen tip and virtual line can be used to reduce or eliminate drift issues.

[0065] In embodiments, digital content is presented to a wearer of the HWC 102 and the wearer moves the pen 200 along a writing surface guided by the digital content for pattern recordation, recognition and presentation assistance. In embodiments, a camera in the HWC 102 images and tracks the positions of the pen 200 for pattern recordation and recognition assistance. In embodiments, both the digital content and the camera capturing the pen positions are used for pattern recordation and recognition assistance. In embodiments, the digital content, camera capture, in-pen camera capture, in-pen IMU, etc. may be used in combination for pattern recordation and recognition assistance. In embodiments, the relative positions of the pen strokes to the virtual line may be presented in the HWC 102 displays in relation to the virtual line. For example, the wearer of the HWC 102 may be scribing without ink in relation to the virtual line that he perceives and as presented in the HWC 102 display, the on-board HWC 102 camera may capture the scribing, a processor may interpret the imaged scribing in relation to the line such that the scribing can be converted into digital content to be displayed in the HWC 102 display in relation to the virtual line.

[0066] FIG. 8 illustrates a system where a camera in the HWC 102 is used to track pen 200 motions and digital content is presented to the wearer of the HWC 102 to assist the wearer with writing within a structure. In this embodiment, digital content in the form of a line 804 is presented in an FOV 802 of the HWC 102. The wearer can see through the FOV 802 so the line 804 appears to augment the surrounding environment's view for the wearer. The line may be ‘fixed’ to a spot in the environment such that when the wearer turns his head and hence changes the position of the HWC 102, the line appears to stay in position with respect to the environment. In embodiments, the camera in the HWC 102 may image the environment and track the relative movement of the HWC 102 with respect to the environment such that the line 804 can be positioned and moved within the FOV in accordance with the imaged movements to maintain visual alignment of the line with a point, object, marker, etc. in the environment. This configuration presents a virtual line in the environment that does not appear to move as the wearer's head moves. The virtual line can provide the wearer with guidance on where to make pen strokes. The line can be thought of as a line on a piece of paper so the wearer can write, or make strokes in a writing pattern, along the virtual line to make prediction of the lines pattern more accurate and overcome drift errors that may otherwise be apparent when attempting to record the movements and predict the patterns.

[0067] With the virtual line presented and virtually connected to a position in the environment, the wearer can use the line for guidance when making writing patterns. The HWC 102 camera can also be used to track the movements of the pen 200 relative to the position of the virtual line. This may be used to better predict the patterns indicated by the wearer's pen strokes. As described herein elsewhere, the pen 200 may track its motions through a pen tip camera and IMU. In embodiments, the pen tip camera and IMU may track the pen's motion and the camera may be used to track the motion of the pen relative to the virtual line. Each of these inputs may be used to track, record and predict what it being written.

[0068] In embodiments, the camera in the HWC 102 captures images of the wearer's pen's motion while the wearer is using the pen to make patterns with the virtual line as a guide. The virtual line may then be overlaid on the captured images of the motion to assist with the pattern analysis. In embodiments, once the overlay is made, one can see or analyze how the pen pattern moved with respect to the position of the virtual line as the wearer may be viewed the virtual line. The pattern analysis may involve interpreting the IMU motion detection, in-pen motion detection, and/or the pen's motion as captured through the HWC 102 camera relative to the virtual line. For example, if the IMU indicates that the pen shifted away from the wearer but the position of the pen relative to the virtual line indicates the pen was not moving, the portion of IMU data that indicated the shift may be discounted in the prediction analysis. The virtual line pattern analysis may be done in real-time, after the fact, etc. The pattern recognition may be done on a processor on-board the HWC 102, remote from the HWC 102, or partially on-board and remotely.

[0069] In embodiments, the virtual line may take any number of forms. For example, the virtual line may be a line, part of a virtual note, part of a virtual message template, etc. The line may also change positions and shapes depending on the wearer's needs. For example, the wearer may want to trace a pattern that is being displayed as digital content and the digital content may be presented as a consolidated image, part of an image, image in a line-by-line presentation format, etc. In embodiments, this system may be used for lessons on writing, painting, drawing, etc.

[0070] Another aspect of the present invention relates to the projection of imagery from a head-worn computer, wherein a projector with x-y mirror control and a solid state lighting system are mounted in the head-worn computer and positioned to project a raster style image onto a nearby surface.

[0071] FIG. 9 illustrates a projection system according to the principles of the present invention. In embodiments, the HWC 102 has a micro-mirror projector 902 adapted to project a raster style beam of light to generate an image on a nearby surface. The micro-mirror projector 902 may include two movable mirrors for the x-y directional control of the light source or a single mirror that has movement on two independently controlled perpendicular axes for x-y directional control. The light source may be a monochromatic, multi-chromatic, dual color, tri color, multi-colored, or other arrangement. In the embodiments where multiple colors are used (e.g. red, green, and blue) the colors may be sequentially provided, simultaneously provided, or otherwise provided by a solid -state lighting system (e.g. LED, Laser, etc.). It should be understood that the term “raster” is being used herein as an example of a pattern that may be projected to produce the image on the nearby surface and it should not be considered limited to any one particular pattern unless otherwise stated. Further, while embodiments refer to a “nearby surface” it should be understood that this is also an example for the reader and that it should not be considered limited to any particular distance unless otherwise stated.

[0072] The micro-mirror projector 902 may project an image for display (e.g. a map, presentation, etc.), an interactive user interface for the HWC 102 (e.g. an interactive keyboard, cursor control interface, button, touch pad, etc.), an interactive user interface for an external device 108, interactive content for multiple participants (e.g. a map, game, etc.).

[0073] In embodiments, an interactive user interface may be projected by the micro-mirror projector 902 and a sensor system may be included in the HWC 102 to make interpretations related to the intersection of the person with the image. For example, the sensor system may detect that the person has ‘touched’ the letter “a” on a projected keyboard and provide the detection information to a processor that determines that the person has ‘pressed’ the letter “a.”

[0074] In embodiments, a sensor system may be included in the HWC 102 adapted to sense an interference when there is an object between the micro-projector 902 and a nearby surface and the interference information may be used to modify the projected image such that the projected image does not project onto the object. For example, the micro-mirror projector 902 may project a keyboard onto a nearby surface and when the user places their fingers over the keyboard the sensor system can detect the interference from the fingers and the projection can be modified such that the projection is dark, not emitted, in the area of the interference so the user's finger or hand does not have a projected image on it. In an example, the micro-projector can project the keyboard onto the surface. An image of the projected keyboard is captured by the camera in the HWC and this image is used as a baseline for comparison. Images are then captured periodically of the keyboard and compared to the baseline to determine whether fingers are present and where the fingers are located. The image of the projected keyboard is then modified to remove the portions of the keyboard where the fingers have been determined to be located.

[0075] In embodiments, the solid state light used in the micro-mirror projector is a non-visible laser or LED (e.g. NIR, IR), such that the projector projects an invisible image. The invisible image may be detected through the use of a matching non-visible light detector or camera. This may be used to prevent others from seeing what the user of the HWC 102 is seeing by providing the HWC 102 with the detector and then displaying visible image content in the see-through display of the HWC 102 that matches the non-visible radiation. This may also be used to project an image for someone else to see if they have a matching non-visible detector system.

[0076] In embodiments, the position of the projected image from the micro-mirror projector 902 is controllable through the HWC 102. The position, for example, may be settable through a user gesture, external control device, HWC 102 mounted interface, etc. In embodiments, the position is locked in place on the nearby surface. For example, once positioned, an adjacent object or a marker on or proximate the nearby surface may be used to ‘key’ the projected image to such that the projected image maintains a relative position on the nearby surface. In this case, the projected image is stabilized relative to the key, so that as the HWC moves, the projected image is moved within the display field of view to maintain a constant relative position to the key, this is also known as a world-locked image.

[0077] In embodiments, the micro-mirror projector 902 has an image stabilization system. The image stabilization system may move the micro-mirror projector 902 to compensate for sensed vibrations or other movements of the HWC 102 such that the projected image appears stably positioned on the nearby surface even when there are vibrations or movements (e.g. small movements) of the HWC 102.

[0078] An aspect of the present invention relates to a gyro-stabilized image projector with gimbaled mounts to provide a physically stabilized projection platform. In embodiments, the projection is world locked such that the projected image appears in a fixed position relative a surface, surface edge, marker, etc. The world locked projection maybe gyro-stabilized with a laser rasterized projection where an IMU is used to measure movements of the head-worn computer and then small motors (e.g. piezo electric motors) are used to stabilize the projector/raster mirror(s). In an alternate embodiment, the projected image passes through optics that include optical stabilization wherein the position of optical elements can be laterally moved to change the pointing direction of the projector in response to sensed movements of the HWC.

[0079] In addition to optical stabilization, the projected user interface may also be, or instead be, digitally stabilized. The digitally generated image of the projected user interface can be digitally shifted laterally across the projected field of view to stabilize the user interface as seen by the user. Provided the projected user interface (e.g. the keyboard) only occupies a portion of the projected field of view. For example, where the keyboard occupies 20 degrees of a 30 degree projected field of view, the projected image can be digitally stabilized for movements of +/−5 degrees by digitally shifting the image to compensate for detected movements. In embodiments, movement detection can be accomplished by detecting movements of the HWC or by detecting movements of objects in the camera's field of view or through a combination of both techniques.

[0080] Another aspect of the present invention relates to generating the projected image through a diffractive optical element. In embodiments, the IMU stabilized laser is arranged such that the user interface image is generated by the diffractive. The laser may be attached to the diffractive and the combined device may be pointed by actuators to align and stabilize the image. In embodiments, the diffractive is removable and replaceable such that the user can change what projected image is to be presented by the projector. For example, the HWC 102 may be provided with a set of diffractives, one for a keyboard, button, slider, etc. and each one may be removed and replaced in the HWC 102.

[0081] An aspect of the present invention relates to a projected or augmented reality content displayed user interface position and focal plane along with the focal plane for content resulting from an interaction with the user interface. For example, as described herein, a keyboard or other user interface may be projected from an HWC 102 onto a surface. The user may interact with the image that appears on the surface and the HWC 102 may have an interaction identification system (e.g. structured invisible wavelength light pattern recognition system, motion and distance sensor system, etc.) such that the interactions produce output (e.g. key strokes relating to keyboard interactions). The output, or response to the interactions, may be displayed in the see-through display of the HWC 102 at a position and at a focal plane that is in relation to the position and focal plane of the surface and area where the projected user interface is displayed. In embodiments, the position may be such that the resultant content does not overlap the user interface from the user's perspective. In embodiments the focal plane for the presentation of the resultant content and the user interface display surface may be different to form a workspace where the user can either focus on the user interface or the resultant content, but not both simultaneously. In embodiments, the position of the resultant content may be world-locked in relation to the projected user interface such that they appear to maintain a constant positional relation to one another from the user's perspective. This can be a useful arrangement for user's that are touch typers where they focus mainly on the resultant content but occasionally want to view the keyboard.

[0082] In other embodiments, the resultant content may be positioned and locked in a position near the projected or displayed user interface and have the same or similar focal plane as the user interface. This arrangement may be desirable for those users who like to look back and forth between the resultant content and the keys of a keyboard, for example.

[0083] In embodiments, the user may affirmatively control the position and focal plane of the resultant content relative to the projected or displayed user interface. The selections may be set as default settings, temporary settings, contextual settings (e.g. a selection based on the application being used in the HWC 102, a selection based on the surface in use for the reference projection or display, time of day, sensor feedback (e.g. if a motion sensor identifies motion a certain setting may be used), environmental conditions, etc.

[0084] In embodiments, the resultant content may be presented through a display other than the head-worn see-through display. For example, the user may want to display the content to other people, either proximate or remote from the user, so the user may elect to cause the resultant content to be presented on another system display.

[0085] Another aspect of the present invention relates to maintaining a proper shape of a projected or display user interface during movements of the HWC 102. In embodiments, the user interface is presented as a world-locked item, meaning it is positioned through a fixed reference to something in the surrounding environment such that it appears to be locked in place even as the user moves his head and eyes. In embodiments, the user interface is also stabilized such that relatively small movements of the user's head don't cause the user interface to appear to shake or move in an unwanted fashion from the user's perspective. In a further embodiment, the shape of the projected user interface may be monitored and adjusted to maintain its intended shape as to be viewed from the user's perspective (e.g. to correct for keystoning). For example, the surface or edges of the surface may be monitored for shape alignment and when the HWC 102 moves enough to cause the shape to otherwise change with respect to the surface reference, the projected user interface shape may be altered to maintain the properly aligned shape. In embodiments, active surface alignment may be accomplished through an imaging process where the camera in the HWC 102 is used to image the surface. In embodiments, the shape modifications may be accomplished based on a predictive system. For example, an IMU may monitor the movements of the HWC 102 and the IMU output may be used to predict the resulting changes in a projected user interface image such that the user interface image can be reshaped based on the movements. In embodiments, the shape management may involve both surface imaging and motion-based predictions. In embodiments, the projected or displayed user interface may further be digitally stabilized.

[0086] Another aspect of the present invention relates to cutting away a portion or all of a displayed or projected user interface based on movements of the HWC. In embodiments, the user interface is world locked and either a portion or the whole user interface will be cut off if the HWC 102 moves too much. For example, in the situation where a keyboard is being projected onto a surface and the keyboard is world-locked to the surface, a portion of the projected keyboard may be eliminated when the user turns his head to the side. This prevents the projector from projecting the image erroneously. The projector will only have a certain relatively small adjustable range to target the surface and once the end of the range is reached, for example, the projection can stop or the projected image can be altered in such a way that only a portion of the projected user interface still appears. When projecting a portion of the user interface in such a situation the content being projected may need to be altered. For example, as the right side of the projection is getting cut off, the digital content may be altered such that the left portion of the content continues to appear clear.

[0087] Another aspect of the present invention relates to world-locking a projected or displayed user interface based on a user presented marker. In embodiments, a user of a HWC 102 places a high contrast marker or makes a high contrast mark such that the HWC 102 has a reference for the world-locking of the user interface. In embodiments, the marker or mark may be intended to be used multiple times, such as a mark on a table top where the user periodically sits. In embodiments, the marker may be intended as a one time or limited time mark, such as a mark in the sand or on some surface that the user does not frequently visit. In embodiments, the marker or mark may be used to world-lock the user interface where the mark is directly associated with the placement for a portion of the user interface. In other embodiments, the marker or mark may be used as a remote reference for which the user interface will be referenced but which the user interface will not overlap. This can be useful in situations where the user wants to move the user interface on the surface. For example, the user interface may be projected in an original position and the HWC 102 may give the user the opportunity to move the user interface on the world-locking surface. The user may then use a gesture, such as touching the user interface projection and dragging it into the preferred position. Then the HWC may continue to use the mark or marker as a reference or if another marker is recognized as being available the new marker may be used.

[0088] In embodiments, the user generated marker is not visible to the human eye but can be detected by the HWC 102. For example, quantum dot ink or other infrared active material may be used to make a mark that is invisible to the human eye but is visible when viewed in infrared and the HWC 102 may include an infrared camera capable of detecting the infrared light emitted from the mark. The quantum dot ink or other infrared active material may fluoresce infrared light in response to visible light or near infrared light. Similarly, the mark may be visible in ultraviolet light but be invisible to the human eye, and the HWC then includes an ultraviolet camera.

[0089] Another aspect of the present invention relates to capturing user interactions with the projected or displayed user interface through a projection of structured light and capturing and interpreting changes in the structured light caused by user movements. In embodiments, the structured light is projected through a diffractive to generate a known pattern of light. The structured light projector may be built into the HWC 102, IMU stabilized and coordinated with the user interface projector to maintain an alignment with the projected user interface image. In embodiments, the structured light will cover the user interface such that physical interactions with the area involving the user interface can be identified and interpreted. The structured light is typically not visible to the user because it is can be a very busy pattern that would be distracting to the user. In embodiments, the HWC 102 includes a non-visible capture system (e.g. IR camera) to capture the structured light interference patterns.

[0090] In embodiments, a user's finger positions can be calibrated into the structured light system or stereo camera 3D imaging system by having the user start with all fingers in contact with the surface. By measuring the positions of the fingers in contact with the surface by using the structured light system or stereo camera 3D imaging system, a baseline position of the fingertips when in contact with the surface can be obtained. When a fingertip later reaches this baseline position, it can be interpreted as having contacted the surface and a keystroke or other input can be determined on the projected or displayed keyboard or user interface. This is particularly advantageous when the structured light or stereo camera 3D imaging system views the surface and the user's fingers from a perspective wherein the movements of the user's fingers are away or toward the HWC, because then the movements of the user's fingers are limited by the surface. The position and angle of the surface relative to the user interface can also be determined by using the structured light system or stereo camera 3D imaging system. The position and angle of the surface can be used to more accurately determine the baseline position of the fingers over the entire area of the projected or displayed keyboard or user interface so that keystrokes can be more accurately identified.

[0091] In embodiments, a displayed or projected user interface (e.g. a keyboard) and other displayed information are provided to the user in correspondence with the head pose of the user. Wherein the head pose is determined by the measured tilt of the HWC as determined by a tilt sensor associated with the HWC. In this case, the displayed or projected user interface is only provided when the user's head pose is at a selected angle or range of angles such as when the user's head is tilted downward by 30 degrees as is typical when using a laptop computer. When the user, raises their head above this tilt angle, the user interface is not provided and their finger movements are not tracked. If the user then tilts their head down again, the user interface is once again provided and their finger movements are tracked to determine their interactions with the user interface. In a similar fashion, the user interface can be provided when the user's head pose is within a selected lateral angle or range of angles and if the user moves their head laterally, the user interface is not provided. This method of providing the user interface only when the user's head pose is within a selected position, encourages the user to keep their head still as is typical when a person is typing or interacting with a graphical user interface. Although, it is within the scope of the invention to provide a stabilized displayed or projected user interface within the selected range of angles. In this way, a simplified method of world locking the user interface without having to track objects in the environment is provided. Instead, the method relies on tracking the head pose of the user within a selected range of angular movements to determine when a displayed or projected user interface is provided to the user. The method can also be provided as a mode that is selected by the user of the HWC. In addition, providing the user interface can be combined with the providing of other information that is displayed in the HWC when the user interface is not displayed. For example, when the user has their head tilted downward, the user interface can be displayed or projected and when the user tilts their head upward the other information is provided while the user interface is not provided.

[0092] In embodiments, the user interface is projected using non-visible light where the non-visible light is imaged by the user, or other user, and the user interface is then presented as an augmented reality overlay in the head-worn display. For example, the structured light could be provided at 940 nm (e.g. with an LED or laser diode), which can still be captured by a standard CMOS or CCD camera with the infrared cut filter removed. The keyboard could then be projected with 808 nm light (e.g. with an LED or laser diode) and captured with a standard camera. In embodiments, the image may be captured with the same camera and the images may be image processed to identify the different wavelength patterns. In other embodiments, this may be accomplished with two cameras wherein one camera is used to capture the structured light and the other camera is used to capture the projected image and each camera is blocked from light associated with the other image (e.g. by including a notch filter that transmits certain wavelengths of light while reflecting or absorbing other wavelengths of light).

[0093] In embodiments, the structured light pattern and projected user interface are world locked, stabilized, and image shape corrected in a coordinated fashion to maintain proper alignment between the two and such that proper identification of user interactions can be identified as properly aligned with the user interface elements. For example, both the structured light projector and user interface projector may be physically stabilized (e.g. as described herein), digitally stabilized (e.g. as described herein) and shape corrected to compensate for head movements (e.g. as described herein).

[0094] In embodiments, IMU's are attached to the back of a user's hand, finger, and or knuckles to detect finger movements and surface contact by detecting sharp stops in movement. This can provide a more detectible key contact to go along with detection of finger movements with systems.

[0095] Another aspect of the present invention relates to capturing user interactions with a projected or displayed content user interface through 3D imagery of the user's fingers as captured by two separated cameras mounted on a head worn computer. For example, a camera may be mounted on ends of the front facing side of the HWC 102 (e.g. near the glasses lenses) and the two cameras may simultaneously capture video of the user's fingers while the user is interacting with a projected or content displayed user interface (e.g. a projected keyboard or AR content displayed keyboard). As the cameras capture the images, the images from the separate cameras can be processed to generate a 3D model of the user's movements such that interactions with the projected or display user interface (e.g. virtual interface) can be determined. In embodiments, the dual separated cameras may capture other user body part movements such that they can be interpreted as 3D gesture commands.

[0096] Another aspect of the present invention relates to technologies for launching a projected or displayed user interface. In embodiments, the user interface may be activated (e.g. projected or displayed) based on an affirmative user action, contextual information or other information. For example, if the user launches a software application on the head-worn computer that interoperates with a particular type of user interface (e.g. a keyboard, button, mouse, touch pad), the user interface may be presented to the user automatically. In embodiments, the user interface may be presented when appropriate during the experience with the software application. For example, if the user launches an email application, the user may automatically be presented with a ‘reader's’ user interface such as a projected or displayed touch pad. The user may use the touch pad to interact with the email program to assist in reading, scrolling, moving to another email, etc. The user may also use the touch pad to reply or start a new email, which is an action that may cause the user interface to alter and include a keyboard to facilitate the input of text. In other embodiments, the user may use another external user interface to launch the projected or displayed user interface. For example, the user may have a pen or watch interface (as described herein) and the pen or watch may be adapted to launch the projected or displayed user interface. The user may then use the pen or watch for certain interactions and then quick launch an additional user interface (e.g. a projected or displayed keyboard). The user may also use a user interface mounted on the head-worn computer to launch the projected or displayed interface.

[0097] Another aspect of the present invention relates to an invisible user interface that can be viewed by the user of a head-worn computer. In embodiments, the user interface is an infrared fluorescing printed keyboard (e.g. printed with quantum dot ink or infrared active ink) wherein the ink fluoresces in the infrared after being exposed to visible light or near infrared light. The light from the infrared fluorescing printed keyboard, or other user interface or image, can be captured by an infrared camera or hyperspectral camera in the HWC, along with finger movement. Since the printed keyboard is under the user's fingers, the fingers don't interfere with the keyboard image. Stereo cameras or structured light can be used to determine finger movements as has been discussed previously herein. Examples of suitable infrared inks include: http://www.maxmax.com/aXRayIRInks.asp IR1 ink absorbs below 793 nm and emits at 840 nm; or http://www.diversifiednano.com/i-series.aspx x-nano IR-783 absorbs in the visible and emits at 783 nm.

[0098] In a further embodiment, user interactions with the projected or displayed user interface or printed user interface are captured with a time of flight camera system that is associated with the HWC. Where the time of flight camera projects a short burst of light (e g infrared light) onto the user hands and the associated area of the user interface. Light reflected from the user's hands and the associated area of the user interface or keyboard is then captured for a very short period of time by the time of flight camera. The relative distance between the time of flight camera and portions of the user's hands and portions of the associated area of the user interface is then determined from the relative brightness of the different portions of the image of the scene as captured by the time of flight camera. As such, the time of flight camera provides a depth map of the user's hands and the associated area of the user interface. Changes in the depth map are used to determine the movements of the user's hands in relation to the user interface.

[0099] Although embodiments of HWC have been described in language specific to features, systems, computer processes and/or methods, the appended claims are not necessarily limited to the specific features, systems, computer processes and/or methods described. Rather, the specific features, systems, computer processes and/or and methods are disclosed as non-limited example implementations of HWC. All documents referenced herein are hereby incorporated by reference.