TWI281042B - An image transmission system - Google Patents

Abstract

The present invention discloses an image transmission system. It comprises a laser apparatus and an optical glass with diffraction optical elements (DOEs). The image transmission system according to the present invention can selectively transmit the video to the user with DOE glass.

Description

1281042 IX. Description of the Invention: [Technical Field of Invention 4] The present invention relates to an image transmission system, and more particularly to an image transmission system equipped with optical glasses having a diffraction optical element (DOE) . [Prior Art] At present, the conventional video playback devices are directly broadcasted to the viewer in front of the display panel via a display panel, such as a television, an LCD panel, a plasma TV, and an OLED panel. Therefore, the viewer can view the image as long as it is in front of the display panel. However, the conventional image playback device cannot achieve a confidential effect; that is, it is impossible to play an image for a specific person. In some special places, such as the investigation office of the conference and the police unit, it is necessary to have a confidential and highly selective video playback device. Therefore, in order to solve the above problems, it is desirable to provide an image transmission system to overcome the disadvantages of the prior art. SUMMARY OF THE INVENTION An object of the present invention is to provide an image transmission system that uses a laser device and an optical lens having a light diffraction element to selectively play an image to a user wearing the optical lens. To achieve the above object, the present invention provides an image transmission system including a laser device for generating a laser beam having a stereoscopic image.

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It is to be understood that the disclosure of the present invention is intended to be illustrative of the present invention and is not intended to limit the invention to the specific embodiments illustrated and described. Referring to Figures la and lb, respectively, the laser device 10 and the optical glasses 20 having the light diffractive element 21 are disclosed in accordance with the present invention. The image transmission system includes a laser device 10 and an optical lens 20. Referring to Figure 2, there is shown a laser device 10 for an image transmission system in accordance with the present invention. The laser device 10 includes a housing; a laser source unit 12; a first motor 15; a second motor 16; a fixed mirror 18 and a circuit unit 17. The housing is used to cover and protect the internal circuitry of the image transmission system. The laser source unit 12 is for generating a laser beam having an image 30. The first motor 15 is for rotating the first mirror 13. The second motor 16 is for rotating the second mirror 14. The fixed mirror 18 is for reflecting a laser beam from the first mirror 13 and the second mirror 14. The circuit unit 17 is for controlling the rotational speed of the first motor 15 and the second motor 16. The image 30 controls the rotation speeds of the first motor 15 and the second motor 16 via the circuit unit 17, and the laser light source unit 12 can generate a stereo image by the rotation speed of the first motor 15 and the second motor 16. 30. The stereoscopic image 30 is transmitted to the user by laser light. The lens of the optical glasses 20 has a light diffractive element 21 for

FE021-P446-TW 1281042

The principle of splitting of element 21. In Fig. 5a, when the wavefront shape of a light is not a plane wave, it can be mathematically calculated by Fourier transform, and this wavefront can be composed of many plane waves of different intensities. In Fig. 5b, when a parallel light is incident on the light diffraction element 21, the wavefront is changed. When the surface shape (i.e., score) of the light diffraction element 21 is controlled, the traveling direction of different incident waves can be controlled. Since the relationship between the refractive index η of the substrate medium and the thickness affects the wave propagation speed, it can be used to design the direction of advancement affecting the wavelength, and the light of the object to be displayed is further imaged 31 on the second mirror 14. Referring again to Fig. 3, a schematic diagram of the operation of the image transmission system has been described. The basic principle of the light diffractive element 21 is in the form of phase modulation, using scalar diffraction theory or vector diffraction theory; after calculation, the surface profile changes. After the invention of holography, the concept and principle of diffractive optics were further applied to micro-optical components such as beamsplitters and lenslets. The basic design flow of the light diffractive element 21 is to first calculate the interference pattern of a particular wavefront, which is a computer-generated hologram (CGH). Then, the simulated interference pattern is calculated by the digital plotter output, and finally the thumbnail image is obtained. The phase of the incident surface light field is modulated by the change of the surface profile, and the phase of the exiting surface light field is controlled to obtain the distribution of the predetermined outgoing optical space energy. The design rule of the light diffractive element 21 is roughly divided into four kinds of architectures: · the first is an optical path method; the second is a scalar diffraction theory; the third Is strictly rigorous coupled wave theory; the fourth is waiting

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Effective medium theory. The optical diffractive element 21 of the present invention is preferably designed using a scalar wave diffraction method. The scalar wave diffraction method is based on the phenomenon of light fluctuations to describe the diffraction phenomenon of light. Also known as fourier optics. The wave of light says that every point on the wavefront can be thought of as a secondary spherical source, that is, the wave packets of all new sources will form a new wavefront. The light diffraction element 21 is designed to advance the light passing through the light diffraction element 21 in accordance with the wavelength of the incident/exit light and the refractive index of the substrate. The diffraction efficiency is related to the number of a plurality of light diffraction unit cells 22 on the light diffractive element 21. The dielectric thickness of the plurality of light diffraction unit cells 22 determines the diffraction direction of the incident light wavefront. The plurality of light diffraction unit lattices 22 are used to disperse light of a plurality of beams of different directions and angles to achieve uniform energy distribution. The plurality of light diffraction unit cells 22 have a thickness of no more than 10 um. The diffraction angle of the plurality of light diffraction unit cells 22 is not more than 90 degrees. In the imaging 31 mechanism, since the light diffring element 21 is the most different from the conventional general lens, the relationship between the object distance (P), the focal length (1) and the image distance (q) is not required. Therefore, when the laser beam having the image 30 is incident on the light diffractive element 21, the image 31 is perfectly formed. It should be noted that the image 30 must be visible only with the optical glasses 20 having the light diffractive element 21. Again with Figure 3 to illustrate the DOE process. The manufacturing method of the DOE of the preferred embodiment of the present invention employs, but is not limited to, a photomask lithography (yellow lithography) process. On a transparent substrate, such as quartz, glass substrate,

10 FE021-P446-TW 1281042 Explanation, all types of corrections and changes can be made without destroying the spirit of this invention. Therefore, the scope of the invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS In order to make the above and other objects, features and advantages of the present invention more apparent, the preferred embodiments of the invention.

Figure la shows a laser device; Figure lb shows an optical lens with a light diffractive element; Figure 2 shows a laser device according to the present invention; Figure 3 shows a schematic view of the operation of the image transmission system; Figure 4 shows the difference in function and appearance between the diffractive optical element and the refracting optical element; Figure 5a shows a schematic representation of many different directions and intensities for the conversion of planar light by Fourier and Figure 4b. The principle of splitting of the light diffractive element. [Main component symbol description] 10 laser device Π laser light exit hole 12 laser light source unit 13 first mirror 14 second mirror

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15 first motor 16 second motor 17 circuit unit 18 fixed mirror 20 optical glasses 21 light diffracting element 22 light diffraction unit lattice 30 image 31 imaging

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Claims (1)

a fixed mirror, a base disposed in the housing for reflecting a laser beam from the first mirror and the second mirror; and a circuit unit disposed in the base of the housing And controlling the rotation speed of the first motor and the second motor. 3. The image transmission system of claim 2, wherein the substrate of the light diffraction element is selected from the group consisting of a glass substrate, a thick film of indium tin oxide, and a transparent photoresist. 4. The image transmission system of claim 1, wherein the optical diffraction element is fabricated by a microelectromechanical process. 5. The image transmission system of claim 2, wherein the thickness of the light diffraction unit lattice is an integer multiple of two. 6. The image transmission system of claim 2, wherein the order of the thickness variation of the light diffraction unit lattice is 4th order. 7. The image transmission system of claim 2, wherein the plurality of light diffraction unit lattices have a length of 16 um. 8. The image transmission system of claim 1, wherein the dielectric thickness and refractive index of the plurality of optical diffraction unit lattices determine a diffraction direction of the incident light wave. 15 FE021-P446-TW 1281042 9. The image transmission system of claim 2, wherein the plurality of light diffraction unit lattices have a thickness of no more than 10 μm. 10. The image transmission system of claim 2, wherein the plurality of light diffraction unit lattices have a diffraction angle of no more than 90 degrees. 16 FE021-P446-TW