Background of the Invention
The present invention relates to a light ray radiating device, in particular a light ray radiating device for effectively dispersing light ray energy emitted from an optical conductor cable into a direct-light ray component and into an indirect-light ray component in order to cultivate plants more effectively and when using light ray energy transmitted through an optical conductor cable to activate the photo-synthesis process.
In order to effectively cultivate plants, a proper amount of nutritious substances, light rays, carbon dioxide, water, humidity, etc. is needed. However, it is difficult to provide all of them in the right amounts. and furthermore the cultivation of plants requires the earth as a foundation to be employed as a mother-body for cultivating plants.
However, in urban areas, such as in a megalopolis, it is not easy to acquire space for cultivation. Especially, it is very difficult to secure soil in the sun required for the cultivation of plants. In order to solve such a problem, the present applicant has previously proposed focusing solar rays by the use of a lense or the like, to guide them into an optical conductor cable, and to further guide the same through the optical conductor cable onto a plant cultivating device installed in an optical, desired place for the purpose of supplying solar ray energy to plants. The present applicant has further proposed another plant cultivating device in which artificial light rays were utilized in addition to solar rays collected as described above. (For instance, refer to the U.S. Pat. No.; 4,653,223.)
In order to effectively cultivate plants, direct solar rays and indirect solar rays are needed. Conventionally and previously a light source device capable of effectively radiating onto plants such direct solar rays and indirect solar rays had not been proposed.
Summary of the Invention
It is an object of the present invention to provide a light ray radiating device capable of effectively radiating onto plants direct solar rays and indirect solar rays.
It is another object of the present invention to provide a light ray radiating device, the ratio of direct light rays and indirect light rays can be selected optionally to a desired value for supplying both types of light rays to plants, and thereby the plants can be more and more effectively cultivated.
The above-mentioned features and other advantages of the present invention will be apparent from the following detailed description which goes with the accompanying drawings.
Brief Description of the Drawings
FIG. 1 is a construction view for explaining an embodiment of the present invention; and
FIG. 2 is a cross-sectional view for explaining the details of the light diffusing and reflecting type liquid-crystal plate shown in FIG. 1.
Description of the Preferred Embodiments
FIG. 1 is a construction view for explaining the embodiment of a light ray radiating device according to the present invention. In FIG. 1, 1 is an optical conductor cable through which the light ray energy is transmitted, 2 an upper plate having a hole through which the light-emitting end 1a of the optical conductor cable 1 is inserted at the approximate central portion of the upper plate, 3 a light diffusing and reflecting type liquid-crystal plate (a lower plate) disposed so as to be opposed to the light-emitting end 1a of the optical conductor cable 1, 4 a frame body for unitarily assembling the upper late 2 and the lower plate 3, and 5 an intermediate plate capable of moving in the direction shown by an arrow marked A or B in the frame body 4 between the upper plate 2 and the lower plate 3 and having a central portion capable of passing light rays therethrough. The circumferential portion 5a of the intermediate plate 5 is constructed of a mirror plate or a light diffusing and reflecting liquid-crystal plate.
FIG. 2 is a cross-sectional view for explaining an embodiment of the light diffusing and reflecting type liquid-crystal plate 3. The liquid-crystal plate 3 comprises an upper transparent electrode plate 3a, a lower transparent electrode plate 3b, and diffusing and reflecting liquid crystal 3c hermetically sealed between the electrode plates 3a and 3b. When the voltage is not applied thereto across the electrodes 3a and 3b, the liquid crystal 3c is transparent. On the contrary, when voltage, for instance 10 volts V, is applied thereto across electrodes 3a and 3b, the liquid crystal 3c becomes a light diffusing and reflecting plate.
In FIG. 2, 6 represents lead wires for applying voltage to electrodes 3a and 3b, and 7 is a power supply device. A switch for turning on and turning off the voltage of the power supply or a variable resistor for continuously changing the power supply voltage, or a step switch for changing the same step-wise is installed on the power supply device 7.
By turning the switch on and off, the light diffusing and reflecting liquid-crystal plate 3 becomes a light diffusing and reflecting plate or a transparent plate, and consequently direct light rays or indirect light rays can be alternatively focused onto an optional desired place. And further, it may be possible to continuously change the ratio of the direct light ray components and the indirect light ray components by using adjustable volume (a variable resistor), or else to change step-wise the ratio of the same two components by the use of a step switch.
The central portion 5b of the intermediate plate 5 is hollow and constructed of a transparent plate. Among the light rays radiated from the optical conductor cable 1, only the light rays passing through the hollow portion or the transparent portion 5b arrive at the light diffusing and reflecting type liquid-crystal plate 3 situated at the bottom of the device. On that occasion, when the light rays pass directly through the lower liquid-crystal plate 3 the same are radiated as direct light rays onto a desired place, and when the voltage is applied to the lower liquid crystal plate 3 the light rays are divided into direct light rays and indirect light rays depending on the amount of voltage applied thereto and the light rays are radiated onto a desired place. In the case that the circumferential portion 5a of the intermediate plate 5 is formed in the form of a reflecting plate, when the intermediate plate 5 is moved downwards in the direction shown by arrow A, the direct light ray components, passing through the lower plate 3, decrease, and the light rays reflected onto the reflecting plate portion 5a are radiated as indirect light rays. On that occasion, in order to effectively employ the light rays reflected onto the reflecting plate portion 5a as indirect light rays, the lower surface 2a of the upper plate 2 is formed in the state of a light reflecting surface and the frame body 4 is made of a semi-transparent substance. In such a construction, the light rays reflected on the reflecting light surfaces 5a and 2a are effectively dispersed by those semi-transparent bodies, and therefore the indirect light rays can be effectively radiated.
Furthermore, in case the circumferential portion 5a of the doughnut-like intermediate plate 5 is constructed of a light diffusing and reflecting liquid-crystal plate, the liquid-crystal plate portion 5a becomes a transparent body or a reflecting body as mentioned in connection with FIG. 2, and thereby the light rays can be divided into direct light rays and indirect light rays and radiated more and more effectively.
And further, in FIG. 2, 8 is a light sensor. The intensity of light rays passing through the lower light diffusing and reflecting liquid-crystal plate 3 is detected by the light sensor 8. The voltage applied to the lower diffused reflecting type liquid crystal plate 3 is changed in accordance with the detection signal produced by the light sensor 8. In such a way, it may be possible to radiate the light rays with a desired intensity onto plants.
As is apparent from the foregoing description, according to the present invention, the ratio of direct light rays and indirect light rays can be selected optionally to a desired value for supplying both types of light rays to plants, and thereby the plants can be more and more effectively cultivated.