TW579451B - A liquid crystal display projection system with high performance - Google Patents

Abstract

A liquid crystal display projection system with high performance includes a liquid crystal on silicon and polarization beam splitter. The light beam coming from nonpolarized light source is separated into two polarized rays. The liquid crystal on silicon separately reflects two polarized rays to a projection module of the liquid crystal display projection system. The LCD projection system make full use of the light beam coming from nonpolarized light source, and reduce volume itself by constituting the liquid crystal on silicon and the polarization beam splitter.

Description

579451 V. Description of the invention (1)-[Technical field to which the invention belongs] The present invention relates to a high-performance liquid crystal projection system, and particularly to a miniaturized high-performance liquid crystal projection system. [Previous technology] With the development of projection display technology, projection systems and equipment have developed very rapidly in recent years. Lighter, smaller, and brighter liquid crystal device (Liquid Crystal Device, LCD) or digital light source (DLP, Digital Light Projector), more than the CRT projector (CRT) Projector). A digital light source processing projector (DLP) is a projector constructed using Digital Micromirror Device (DMD) components developed by Texas Instruments. Texas Instruments is currently the only supplier of DMD. It develops semiconductor processes based on its Micro Electric Mechanical System technology. At present, the latest development progress is 0.7 inches. It has a considerable advantage in reducing the size of the projector. . DLP technology completely adopts digital control. It has the advantages of high brightness, fast response time, and no noise. After the light source collects light, it focuses through the lens, passes through the RGB three-color filter, and then scans the turntable to achieve full-color effect. It is then projected onto a micro-mirror chip (DMD), which is composed of tiny micro-lenses. The angular deflection of the micro-reflection slit is generated by the driving electrode and the deflection time is controlled to switch the reflection direction of the light. . Because digital light source processing projectors (DLp) require quite complicated micro-electromechanical mechanisms, the yield is not high, and the supply is still limited; coupled with Texas Instruments' absolute supply advantage, the price problem will also be ~

Page 5 579451 V. Description of the invention (2) Important considerations Among them, the basic principle of the LCD projector is to use the LCD module to modulate the light emitted by the light source. In order to make full use of the light emitted by the light source, most of the elements are a combination of a lens array and a polarization beam splitter array, so that the originally randomly polarized light can be efficiently converted into linearly polarized light. Thereby increasing the utilization efficiency of light in the LCD projector. There are two types of liquid crystal projectors: transmissive and reflective. Transmissive liquid crystal projectors are mainly composed of a liquid crystal panel and a dichroic mirror for splitting and combining light. The light is emitted by a light source module, and is divided into three colors of ^, G, and B through a dichroic bi-color mirror. After the three colors are controlled and adjusted by three LCD panels, they are combined by a light source before the projection lens. The three colors are combined and projected onto the screen through the projector lens. Due to the inevitable trend of miniaturization of its LCD panels, projectors are becoming more and more lightweight. However, as the size of the LCD panel is reduced and the resolution is increased, the opening will affect the penetrating power of the light ’, which will cause the light projector to have insufficient light utilization efficiency. Withered? In terms of projectors, reflective LCD elements are the key technology, and% of them are reflective liquid crystals (LCOS, Liquid Crystal on: Top, 11), and metal oxide semiconductor wafers (CMOS) are used as circuit substrates. , Said 5, and the plate is filled with liquid crystal. The current "⑽reflective technology can be 5 疋 f _ Qiaofa date inch period" unlimited potential in the future, which can effectively improve the brightness ^, and at the same time bring the development of projector resolution into a new era. [Inventive Content]

Page 6 579451 V. Description of the invention (3) In view of the above-mentioned high-efficiency liquid crystal projector (Crystal Si 1 beam splitter), improve the use of light to achieve the above purpose Contains: light source, bias projection module. The present invention provides the light splitting shape of the liquid crystal display light valve required for projection, and is used to project the first use efficiency, and can also horizontally polarize the light to shape the first reflected beam. It can reduce the size of the projector, mini and palm-type. Among them, the present invention integrates three sets of light-emitting elements such as photo-electricity emitters to make them collimated. The detailed description of the present invention is as follows: The problems of the known technology, the object of the present invention is to provide a shadow system, which uses a combination of reflective liquid crystal (LCOS, Liquid IC) and polarization beam splitter (polarization) to reduce the volume structure of the projection system. At the same time, the high-efficiency liquid crystal projection system of the present invention includes a vibration beam splitter, a reflective liquid crystal display light valve, and an unpolarized light source. The light source is used for light; the polarized beam splitter is It is used to convert the vertically polarized light and horizontal polarized light from the light source; the first reflection type reflects the vertically polarized light to form a first reflected light beam; a projection module of the reflected light beam; and in order to strengthen the light, a second reflection type is added The liquid crystal display light valve is used to reflect into a second reflected light beam, which is then projected by the projection module. This method can make full use of the volume structure of the light shirt system provided by the light source, especially the liquid crystal projection system that can be widely used. The light source used can be a photoelectric light emitting element group or a light element as a light source, such as a light emitting diode or a laser diode. The light emitted by the light source can be homogenized in advance, and the characteristics and implementation of the light can be added by adding a lens in front of the light source. The best embodiment is shown below with the illustration. 5759451 5. Description of the invention (4) ----- -[Embodiment] Please refer to FIG. 1, which shows the system architecture of the first embodiment of the present invention. The system architecture includes: three sets of three primary colors (the three primary colors of this embodiment),: ,,, red, green, and blue. Photoelectric light-emitting element group power source (丨 1, 1, 2, 1 3),-light homogenization device 30, a first reflective liquid crystal display light valve (for example, reflective liquid crystal display 7F panel) 40, a second reflective type Liquid crystal display light (for example, ^ -transmissive liquid crystal display panel) 41, a polarizing beam splitter 50, a projection module 60, and a three-way color splitter 70 (for example, Yoshida or X-shaped plate 'I.e. X-plate). The three groups of red, green and blue optoelectronic light-emitting element groups 丨 2, i 3, 丨 4 are used as light sources, and the three-way dichroic device 70 is a first two-way dichroic mirror (dichr). ic mi rror) 71 and a second two-way dichroic mirror 72; the first two-way dichroic mirror 71 Blue light passes and red light reflects; the second bidirectional dichroic mirror 72 allows green and red light to pass and blue light reflects. Two groups of photoelectric light-emitting element groups 1 2, 1 3, and 1 4 emit light of each color. X-plates are used to generate different travel paths, and then pass through the light homogenization device 30 to obtain uniform light; the polarizing beam splitter 50 is used to divide two groups of photoelectric light-emitting element groups (1 2, 1 3 , 1 4) The light emitted is split into vertical and horizontally polarized light; the first reflective liquid crystal display panel 4 is used to reflect the vertically polarized light to form a first reflected light beam, and the second reflective liquid crystal display panel 4 1 It reflects the horizontally polarized light that penetrates to form a second reflected beam; the first reflected beam and the second reflected beam are concentrated on the projection module 60, and the projection module 60 also projects the second reflected beam and the first reflected beam. The reflected beam is then focused on the screen. On the two bi-directional dichroic surfaces of the X-plate 5749451 5. Description of the invention (5) There is less interference between the mirror and the polarizing beam splitter. # ΠίΓΗΤ PTPF, # 1 and 0 are homogenized first The device 30 can be-light s (uGHT PIPE), and the thickness of the light pipe is at least about 2 cm. Qiao Qiguang: J = the group is a set of light-emitting diode (led) clusters: as shown by Van Gogh, it is a schematic diagram of a green light source; 'There are no 6 rows in parallel and 1G Connected in series, the grain group 1 0 1 is set in a thunderstorm! N Q ^ body body day ιοί m: the green light diode crystal grain group 1 101 is formed by concatenation of v lines-the same color Light material, and the positive electrode connected to each of the polar crystal grains is connected to all tomb mines ^ μ ancient eight η, Zeng; u is a V electric sheet 102, the circuit board 103-side swallowed and a metal conductive sheet 102 And grounding piece 104. Later, the above-mentioned light source is integrated into the embodiment, that is, as shown in FIG. 1, two red, blue, and green light diode groups are arranged on both sides of the circuit board. J: and the circuit structure to form red, M, green three groups of light sources, including a cover, to gather light source intensities from a plurality of light-emitting diode grains, each diode group described above is controlled by a light source control circuit 200. Two I i red, '«blue light, green light diode groups are each symmetrically arranged on both sides of the ancient board M3 with a thickness of 8.5 mm (mm) and a thickness of 0.8 mm (dragon), The length of each light-emitting diode grain accounts for about ιΐ 46ι = length, width, and thickness are η · 461 mm, 85 mm, and 12 = only. As shown in Figure 2, the light-emitting diode grains can be They are arranged in small spaces (as shown in the figure); in addition, the side length of the two-way dichroic mirror 1 chr 〇icmirr 〇r can be achieved by the current technology of 13 milliseconds and The reflective display panel can also achieve 1 2.5 mm, and the projection module 60 ° can reach 15 mm (_) and the length can be 25 mm (_) '. Therefore, the invention can achieve projection Purpose of device miniaturization. 579451

Wherein, the reflection type liquid crystal display panel (LiqUid crystal ON silicon, LC0S) can be black and white; when the reflection type liquid crystal display panel is white, the display panel will only display red display screen, blue display, surface and Green display. The reflective liquid crystal display panel can be developed by the sequential color technique. This technology is based on the sequential production of red, blue and green images on the reflective liquid crystal display panel, and the two sets of photoelectric light source group light sources correspond to red. Blue-green light, blue light and green ★ make use of the phenomenon of visual persistence to make people color images. "And, for the light source control circuit for controlling the light source, please refer to FIG. 3, which is a schematic diagram of the first embodiment of the light source control circuit of the present invention. The light source control circuit mainly includes: three discontinuous clock generators (80, 82, 84 \ and three driving circuits (800: 820, 840); the light source control circuit is used to drive and control the photoelectric light-emitting element group, such as the red light-emitting diode grain group 80, the green light-emitting diode grain group 821 and blue light diode crystal group 841. The discontinuous clock generator (80, 82, 84) sequentially generates clocks in turn; the output terminals of the discontinuous clock generator (80, 82, 84) are respectively driven. The input terminals of the circuit (800, 8200, 840) are electrically connected, and the output terminals of the drive circuit (800, 8200) are respectively connected to the red light-emitting diode grain group 801 and the green light-two. The polar crystal grain group 821 and the blue diode crystal grain group 841 are electrically connected so that the three light sources of red, green, and the three light sources are sequentially turned on. When g, the reflective display panel follows; The red, green, and blue images are displayed in order, and the image formed by the three-color light is projected. The phenomenon of visual persistence is a color image in the visual perception of the human eye.

Page 10579451 V. Description of the invention (7) In addition, the light source control circuit of the present invention can be implemented according to another method. Please refer to Figure 4 for the second embodiment of the light source control circuit of the present invention. intention. The light source control circuit mainly includes:

Voltage converters (221, 222, 223), a red-green-blue sequencer (RGB held-sequential color „1 (: Γ〇 (Η3ρ1 ^) 23〇 and three switches (MOSFET swltch) (227, 228, 229) 。Sequencer 23 is to make the red, green and blue light output clocks in different order respectively, please refer to the attachment 丨, the output clock diagram of the bean red green blue sequencer. Sequencer 23 3 clock 2 They are electrically connected to the gates of the three switches (227, 228, 229) respectively; the source of the three switches ^ is grounded, and the drain is electrically connected to one end of the resistor R1, and the other end of the basin resistance R1 is red and green. And the blue diode diode group 2 226), the reverse terminal of the last diode (DU-DN) is electrically connected to the grounding resistor R2; DC-DC voltage converters (221, 222 and red, green And the blue switch (221, 222, 2 23) are respectively arranged at the two ends of the red light diode group 224, the green light diode group 225 and the blue light diode * 226 as their individual driving circuits; Then according to the time, set to drive the red light-emitting diode grain group 224, the green light-emitting diode grain group. 5 and the blue light-emitting diode grain group 226 take turns to emit light in turn, and at the same time more A “Vin supplies power to the DC-DC voltage converter (electricity 223) respectively.” The operation of the second embodiment of its light source control circuit illustrates the red, green, and blue light-emitting diode grain groups (224, 225, 226). ) σ, the chip is electrically connected to the DC-DC voltage converter to obtain a voltage of 撗 ==, for example, the DC-DC voltage converter 2 2 i is connected to red 卞 and ^ —polar body 5749451. Description of the invention ( 8) = 24 器 22 =; = 光 == Power source, · DC-DC final I sheet two ΛΑ β ^ To go to, first pro-polar body-day grain group 225 to supply launch ^ 誃 =, stay power And the DC-DC voltage converter 223 is connected to the @ ^% 极 体 日 日 粒 群 2 2 6 to supply the operating power needed to emit blue light, and the device 23 〇 According to the different pulse widths received,

The output frequency (CLK) of the pulse of Βπΐ is matched with the data bus (DATA 228, 2μΛ), and the red, green, and blue light switches (227, rR) are continuously controlled in sequence. _Stream outputs red light (Red), Green and Blue in order to achieve the purpose of sequentially controlling the color. [Effect of the invention] Fenba provides a new high-performance liquid crystal projection system architecture, which can: use unbiased: outgoing light and reduce the system The volume of its light source, such as integrating multiple groups of photoelectric light-emitting element groups as light: the same setting as the LCD display panel, can greatly improve its straight polarization j light 2: = the light emitted by the polarization beam splitting The device is flat polarized light, so you can use the sequential method of the field of view. Although the present invention moves; to limit the present invention, any. 'The example is disclosed as above, but it is not used within the spirit and scope. The artist does not depart from the patent protection of the present invention ^ 円 Tears ^ Changes and retouching at the beginning of the day, so the present invention shall prevail. ^ ^ Briefly illustrated by the scope of the patent application attached to this specification 5749451 Picture 1 The schematic diagram of the system architecture of the first embodiment is shown in Fig. 2. Fig. 2 is a schematic diagram of a green light source. Fig. 3 is a schematic diagram of a first embodiment of a light source control circuit of the present invention. Fig. 4 is a second diagram of a light source control circuit of the present invention. The schematic diagram of the embodiment; and FIG. 5 is the output clock diagram of the red, green and blue sequence controller of the light source control circuit in FIG. 4 [Illustration of Symbols] 12 Photoelectric light emitting element group 13 Photoelectric light emitting element group 14 Photoelectric light emitting element group 30 Light Homogenizer 40 First reflective liquid crystal display panel 41 Second reflective liquid crystal display panel 50 Polarized beam splitter 60 Projection module 72 Two-way color separator 73 First two-way dichroic mirror 74 Second two-way dichroic mirror 80 discontinuous clock generator 82 discontinuous clock generator 84 discontinuous clock generator 101 Diode grain group

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579451 Brief description of the diagram 102 Metal conductive sheet 103 Circuit board 104 Ground sheet 200 Light source control circuit 800 Drive circuit 801 Diode group 820 Drive circuit 821 Diode group 840 Drive circuit 841-Polar body group 221 DC-DC voltage converter 222 DC-DC voltage converter 223 DC-DC voltage converter 227 Switch 228 Switch 229 Switch 230 Sequencer D11-DN Diode R1 Resistor R2 Resistor

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Claims (1)

579451 6. Scope of patent application 1 · A kind of high-efficiency liquid crystal projection system, which contains · Two separate three primary colors, step by step, intermittently and sequentially sending #-击-盾 A # 斫; first, the original, is used to provide one: \ First two beams of two primary color unpolarized beams; The C device is provided with three sides corresponding to three primary color beams-polarized beam beam splitters, which is a wheeled path of vibration light splitting J into vertical polarized light and horizontally deviated primary color beam non-polarizers. -Side to reflect the vertical polarization;: set: her beam splits the beam; nine to form a younger one reflected image-the other monochrome side of the light reflection valve to reflect the horizontal deviation: = The polarized beam splits the image beam; and firstly, a second reflection shadow and a projection module are used to project the image. 2. As described in the application for patent application, the first beam is used for imaging. The three primary color light sources are Λ Λ = μ ′. ,, ',,, 彔, blue light emitting element 3. The three primary colors are sequential as described in item 丨 of the scope of application for patent η _ Yi 氺 b / night and day technology film system, which controls the light sources to emit light sequentially , Light, source control circuit,, clock production:; = = circuit system 仏 three sets of photoelectric light-emitting element group; and, Ming L generates clock to control the three drive circuits, the discontinuous clock of the ㈣ circuit The input terminals are electrically connected, and the terminals are respectively connected to the output terminals of the 6H drive circuit. 579451 6. The scope of the patent application is electrically connected to the three groups of photoelectric light-emitting element groups respectively, so that the discontinuous clock generator can control the three groups of photoelectric light-emitting element groups. 4. The high-performance liquid crystal projection system according to item 1 or 2 or 3 of the scope of patent application, further comprising a light homogenizing device, the light homogenizing device is disposed between the three-way dichroic device and the polarized beam splitting It is used to uniformize the light beam output from the three-way color separator. 5. The south-efficiency liquid crystal projection system described in item 1 or 2 of the scope of patent application, wherein the light source control circuit includes: a red, green, and blue sequencer, which is used to provide the three different groups of photoelectric light-emitting element groups. Sequential clock output; Three switches: The three clock outputs of the red, green and blue sequencer are electrically connected to the three switches respectively to sequentially control the output of the three switches; and the three DC-DC voltage converters are The two ends of the three groups of photoelectric light-emitting element groups are respectively arranged with three switches as their respective driving circuits. 6. The high-performance liquid crystal projection system described in item 1 of the scope of patent application, wherein the light valves are liquid crystal display panels. 7. The high-performance liquid crystal projection system as described in item 2 of the scope of the patent application, wherein the optoelectronic light-emitting element group has a lampshade externally, and the lampshade can converge the light sources of the light-emitting element group and then project to the three-way color separator. . Page 16