System and method for using a single intelligence circuit in both a digital camera and printer

[0002] This invention generally relates to a system and method for using a single intelligence circuit in both a digital camera and printer, and is specifically concerned with the use of a single PC card to perform the primary data processing operations in both a digital camera and printer to simplify the structure of a camera/printer imaging system.

[0003] Techniques for simplifying the structure of components used in digital imaging systems to reduce manufacturing costs are known in the prior art. For example, in the camera system disclosed in U.S. Pat. No. 5,506,617, and assigned to the Eastman Kodak Company, a digital camera is provided as a module that attaches to the signal bus of a PC compatible computer. This system advantageously eliminates the need for a separate intelligence circuit to be incorporated within the camera itself, as the camera in this system includes a PC-compatible interface connector for mating with a bus extension connector on the computer. Digitized data is directly transmitted from the camera to the signal bus of the computer so that the intelligence circuits of the computer can be used to perform all image processing, storage, and display functions. The elimination of the camera intelligence circuit not only simplifies the circuit architecture, but substantially reduces camera manufacturing costs as the microprocessor used in such circuits costs between $20.00 and $40.00 depending upon the speed and operating abilities required.

[0004] While the camera-computer system disclosed in the '617 patent represents a significant advance in the simplification of digital camera circuitry, its utility is limited since the digital camera must be continuously connected to the PC compatible computer during both the capturing and displaying of images.

[0005] Clearly, there is a need for a completely portable, untethered digital camera that is fully capable of recording images without its own dedicated and relatively expensive microprocessor. Ideally, such a camera could be used in conjunction with a relatively inexpensive thermal or ink-jet printer to produce hard copies of images in photographic form. Finally, it would be desirable if the circuit-simplifying design of the digital camera also allowed the circuitry of the printer to be similarly simplified so that even larger reductions in manufacturing costs could be realized.

[0006] Generally speaking, the invention is an electronic imaging system that utilizes a shared intelligence circuit to fulfill all of the aforementioned criteria. The system of the invention comprises first and second imaging components for capturing and rendering an image, respectively, each of which requires a primary intelligence circuit for operation, and an intelligence circuit that is detachably connectable to either of the imaging components during their operation. The system may, for example, comprise a camera having an imaging sensor for generating a stream of data representative of an image, a printer having a printhead for generating an image from a set of printer instructions, and a single intelligence circuit in the form of a PC card that is detachably connectable to either the camera or the printer for the operation of either. In the method of the invention, the intelligence circuit is first detachably connected to an image capturing component, which may be a camera, in order to convert data stream from an imaging sensor into stored image data. Next, the intelligence circuit is manually removed from the image capturing component, and detachably connected to the image rendering component, which may be a printer. The image rendering component in turn renders an image in accordance with instructions relayed from the intelligence circuit that are generated from the stored image data.

[0007] The use of a single intelligence circuit to operate both a camera and a printer of an imaging system advantageously simplifies the system by obviating the need for separate and largely redundant intelligence circuits presently used in both the camera and the printer, thereby reducing manufacturing costs. The use of a single intelligence circuit also enhances the overall reliability of the imaging system by reducing processing steps and component interfaces.

[0008] In the preferred embodiment, the intelligence circuit is a PC card having a liquid crystal display for displaying either a real-time or a stored image constructed from instructions generated by the microprocessor of the circuit. The PC card preferably includes manually operated controls for capturing, storing, erasing, and scrolling through images generated by the imaging sensor of the camera.

[0009] In one embodiment of the system, the intelligence circuit within the PC card not only stores data from the imaging sensor of the camera, but further includes stored camera and printer-model operating programs for both the camera and the printer that are specific to the particular model and make of the camera and printer. In an alternative embodiment, both the camera and the printer include their own individual stored operating programs in the form of EPROMs. The second embodiment of the system has the advantage of allowing the intelligence circuit to be more versatile, as it can be used in conjunction with a variety of different models of cameras and printers having different features and operational capacities, i.e., zoom lens capabilities, picture editing features, etc.

[0010] FIG. 1 is a schematic diagram of the electronic imaging system of the invention, illustrating how a single, portable intelligence circuit is used to operate either a digital camera or a printer;

[0011] FIG. 2 is a schematic block diagram of the intelligence circuit of the system, and

[0012] FIG. 3 is a plan view of the PC card that houses the intelligence circuit of FIG. 2, illustrating the liquid crystal display and manual controls of the card.

[0013] With reference now to FIG. 1, wherein like numerals designate like components throughout all the several figures, the imaging system 1 of the invention may comprise a digital camera 3, a printer 5, and a shared PC intelligence card 7 which is detachably connectable to either the camera 3 or the printer 5.

[0014] The digital camera 3 includes a lens unit 11 disposed within a movable tubular housing 12 for gathering reflected light from a subject 13 to be photographed. A lens focusing assembly 15 which includes a small DC motor 17, battery pack 19 and gear train 21 is provided for reciprocally moving the tubular housing 12 of the lens unit 11 in a manner well known in the art.

[0015] Digital camera 3 further includes a flash unit 23 which is likewise powered by the battery pack 19 via connector wire 24, and a photometer 25 for measuring the amount of ambient light in the vicinity of the subject 13. Disposed behind the lens unit 11 are an electronic iris diaphragm 27, electronic shutter 29, infrared filter 31, and imaging unit 33, which may be a charged coupled device (CCD) sensor, such as KAF-400 full frame sensor manufactured by the Eastman Kodak Company located in Rochester, N.Y. While not shown in FIG. 1, components 27,29 and 33 are each connected to and driven by the battery pack 19. In operation, light from a subject 13 is focused onto the surface of the imaging unit from the lens unit 11. The imaging unit includes a 640×480 pixel matrix of individual light sensitive elements which collectively generate a data stream representative of the subject 13.

[0016] The digital camera 3 may optionally have any erasable programmable read-only memory (EPROM) 36 which contains an operating program that coordinates the functions of the lens-focusing assembly 15, the flash unit 23, the electronic diaphragm 27 and shutter 29, as well as the activation of the imaging unit 33 whenever the shutter 29 is activated. Finally, the camera 3 includes both a card-receiving slot 38 for receiving the flat, rectangular body of the PC card, as well as a terminal 40 for engaging a row of input and output contacts 41 disposed along an edge of the card 7. In the preferred embodiment, the digital camera 3 may have a structure that is essentially identical to that of the Model DC110 or 220 digital camera manufactured by the previously-mentioned Eastman Kodak Company, the only differences being the replacement of the primary microprocessor and associated programming and memory circuits with the aforementioned card-receiving slot 38 and terminal 40.

[0017] In this example, the printer 5 comprises a thermal printing unit 44 connected to control and power circuitry 46, although ink-jet and other types of printers may be used as well. The printing unit 44 is formed from a ribbon advancing assembly 48 and a printhead mechanism 50, both of which cooperate to thermally render an image onto a sheet of thermal printing paper 52. A movable platen roller 54 supports the printing paper 52 as the printhead mechanism 50 sweeps over it to render an image thereon.

[0018] The ribbon-advancing assembly 48 includes a drive roller 56 connected to the shaft 57 of an electric motor 58 for unwinding a strip of thermal print ribbon 60 from an opposing spool roller 62. The thermal print ribbon 60 is formed from serially connected portions 64 containing cyan, yellow, and magenta coloring agents, respectively. Thermal printing unit 44 further includes a thermal printhead 66 having a linear row of closely spaced heating elements 68 for depositing coloring agents from the thermal print ribbon 60 onto the thermal printing paper 52 by fusion. A paper moving mechanism 70 is provided for moving the thermal printing paper 52 across the thermal matrix printhead 66 while a selected pattern of the heating elements 68 are actuated in order to deposit an image-forming pattern of coloring agents onto the paper 52. Like the drive roller 56 of the ribbon advancing assembly 48, the paper moving mechanism 70 is mechanically powered by the output shaft 57 of the electric motor 58.

[0019] The control and power circuitry 46 of the printer 5 includes a printhead driver and ribbon advance circuit 75 whose output is connected to the electric motor 58 via cable 76. Circuitry 46 also has a printhead controller circuit 77 electrically connected to the heating elements 68 of the thermal matrix printhead 66 via a cable 78. Finally, circuitry 46 includes a power supply 79 which is connected in parallel to the outputs of the circuits 75 and 77. Essentially, the circuits 75 and 77 are power switching circuits formed from an array of power semiconductors whose outputs are modulated by the low-current printer instructions generated by the PC card. In addition to the circuits 75, 77, and 79, the control and power circuitry 46 may further include a EPROM 81 containing an operating program which coordinates the movement of the drive roller 56, paper moving mechanism 70, and the actuation of the heating elements 68. The inclusion of the optional EPROMs 36 to the camera 3 and 81 to the printer 5 advantageously allows the intelligence circuit within the PC card 7 to operate a variety of different imaging systems formed from cameras and printers having different features and capabilities, such as zoom lensing, various picture editing abilities, etc. Finally, similar to the digital camera 3, the printer 5 likewise includes a card-receiving slot 83 for receiving the body of the PC card 7 along with a terminal 85 for engaging the input and output contacts 41 present along an edge of the card 7. The overall structure of the printer 5 may be the same as a Model No. DS 8650 thermal printer manufactured by the Eastman Kodak Company with slot 83 and terminal 85 replacing its microprocessor and associated circuits. Alternatively, a Kodak Model No. HP890C ink jet printer may be used that has been modified in the same manner.

[0020] With reference now to FIG. 2, the intelligence circuit 90 disposed within the card 7 includes a microprocessor 92, and a button-type battery pack 94. Preferably, microprocessor 92 is one of the commercially available family of reduced instruction set computers (known in the art as RISC-type processors) that are relatively fast, math intensive, and application-specific. Examples of such processors include the Model 821 Power PC manufactured by Motorola Corporation located in Phoenix, Ariz., and the Model MIPSR-4000 Processor manufactured by NEC Electronics located in Tokyo, Japan. Such processors are fully capable of rapidly implementing the JPEG still image compression algorithm used to control digital cameras such as the previously-mentioned Model DC110 and 220.

[0021] The intelligence circuit 90 also includes an EPROM 96 for storing an operating program for the microprocessor 92 that allows it to convert the data stream received from the imaging unit 33 into printer instructions. Any one of a number of commercially available EPROM integrated circuits may be used for the EPROM 96 which preferably have a capacity of about 1 megabyte. In order to store the data generated by the imaging unit 33 of the camera 3, the intelligence circuit further has a dynamic random access memory or DRAM 98 that is powered by the battery pack 94. As the imaging sensor 33 preferably has a capacity of 640×480 pixels, the DRAM 98 should have a 20 megabyte capacity in order to store data for 20, one mega-pixel images or 100 compressed images. Examples of commercially available integrated circuits which can be used as the DRAM 98 include the Model MCM51LXXX DRAM manufactured by Motorola, or one of the series of AMD 29C600 DRAMs manufactured by Advance Micro Devices located in Beaverton, Oreg. In both cases, a total of three, 8 megabyte ICs may be used. Optionally, a flash RAM non-volatile memory may be substituted for the DRAM 98, the advantage being that no button-type battery pack 94 would be necessary to preserve data captured in the memory of the intelligence circuit 90.

[0022] The intelligence circuit 90 further includes both a display driver circuit 100 for providing instructions to a liquid crystal image display 104, and a mechanical programmable controller 102 for providing operational commands to the mechanical systems of the digital camera 3 and the printer 5, i.e., the lens focusing assembly 15, and the printhead driver and ribbon advance circuit 75. Driver circuit 100 is normally part of the liquid crystal display module that forms the image display 104, while mechanical programmable controller 102 may be an application specific integrated circuit (ASIC) manufactured by the Eastman Kodak Company in accordance with known technology.

[0023] The intelligence circuit 90 includes a user interface circuit 106 that includes the manual controls and indicator LEDs present on the body of the card 7. All of the components 92, 96, 98, 100, 102, 104, and 106 are interconnected via an address data and input/output bus 107 as is schematically indicated, and with the exception of DRAM 98, all of these components are powered by the battery pack 18 of the camera 3 or power supply 79 of the printer 5.

[0024] With reference now to FIG. 3, the card 7 includes a liquid crystal display (LCD) screen 108. In the preferred embodiment, LCD screen is a low temperature, polysilicon-type screen, as such screens can be made with an overall thickness of approximately 1 millimeter and therefore not significantly contribute to the overall thickness of the body of the card 7. The user interface 106 includes two light emitting diode (LED) indicators 109aand 109bfor indicating whether or not either the camera or the printer is on or off, and further whether or not the button-type battery in battery pack 94 is running low, thereby jeopardizing the integrity of the images stored in DRAM 98. Interface 106 further includes four manually operated arrow buttons 110 which may be used interactively with a control display 114 which appears in a comer of the LCD 108 when the card 7 is in operation. Finally, interface 106 includes an execute button 112 for executing a selected function in the display 114.

[0025] In the example of the control display 114 illustrated in FIG. 3, the system operator has inserted the card 7 into the camera 3 and has further selected the “live picture” function at the top of the display 114 by manipulating bottom-most arrow buttons 110. In such a mode, the LCD 108 acts as a view finder for the system operator, displaying the still frame that will be stored within the DRAM 98 upon the actuation of the electronic shutter 29 of the camera 3. If the system operator wishes to use the card 7 to capture a selected image, he depresses the bottom-most arrow button 110 to light up the “capture” title in the display, and then depresses execute button 112. The number of image frames remaining in the DRAM 98 is displayed in the “frame number” box of the display 114. If the operator wishes to display the frames already stored within the DRAM 98, then he again pushes the bottom-most arrow button 110 to light up the “scroll” box of the display 114, whereupon captured images in the DRAM 98 may be serially scrolled through by manipulating the sideways arrow buttons 110. Of course, a different control display 114 would be exhibited when the card 7 was inserted into the receiving slot 83 of the printer 5. It should be noted that the previously described control scheme on the card 7 has the ergonomic advantage of teaching a first-time user how to operate the printer 5 as the user first learns how to operate the camera 3, since the display, scrolling, and erase functions for both the camera and printer are executed in the same way.

[0026] Although the imaging system of the invention has been described with respect to a specific example, variations, additions, and modifications of this system will become evident to those of skill in the art. For example, while the imaging system has been described in terms of a camera and a printer, the system may be used with any other kind of imaging rendering device, such as an electronic photo-album, a PC video screen, a scanner, a transfer station, or an archive station. The camera may be still or video. While the intelligence circuit of the invention has been described in terms of a PC card, this circuit can assume the form of any portable module that is detachably connectable to both a digital camera or printer. Additionally, the intelligence circuit may perform all, most, or some of the intelligence functions of either the camera or the printer. As has been previously pointed out, the presence of an EPROM having a basic operational program in both the camera and the printer allows the card or other modular intelligence to be used in a number of different types of digital cameras and printers having different functions, i.e., zoom lens capacities, special print-editing functions, etc. All such variations, modifications, and additions are intended to be encompassed within the scope of this invention, which is limited only by the claims appended hereto.