Projection display system and projection display device

Abstract

The application provides a projection display system and a projection display device, and relates to the technical field of micro display. The application introduces a linear polarizer and a liquid crystal lens in a traditional projection display system, controls a unit to identify high gray scale image areas and low gray scale image areas in an image in real time, and respectively transmits the high gray scale image areas and the low gray scale image areas to an LCoS display panel and the liquid crystal lens. A phase correction voltage is applied to a low gray scale lens area of the liquid crystal lens, the deflection angle of a light beam passing through the low gray scale lens area is controlled, the light emitted by the low gray scale lens area is projected to a corresponding high gray scale panel area, the light intensity of the low gray scale panel area is weakened, and the light intensity of the high gray scale panel area is enhanced, so that the problem of low contrast of a traditional LCOS projection display system is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro display, in particular to a projection display system and a projection display device. BACKGROUND

[0002] The projection technology based on Liquid Crystal on Silicon (LCoS) is a reflective display technology, which is widely used in holographic display, virtual reality, augmented reality, projection, head-up display (HUD), laser printing and other fields.

[0003] In the related art, the current mainstream projection display system adopts a variant of the Kohler illumination system, which mainly consists of a light source system, a lens group, a polarization beam splitter, an LCoS display panel and a lens. The lens group is responsible for uniformly distributing the light emitted by the light source system into a rectangular light spot and projecting it onto the LCoS display panel. The liquid crystal inside the LCoS display panel modulates different gray scale information through voltage and reflects the light back to the polarization beam splitter. After passing through the polarization beam splitter, the image is projected onto the display screen. That is, the generation of the entire dynamic image depends on the reflection modulation of the LCoS display panel on the light.

[0004] However, the LCoS panel display system itself cannot effectively shield the low gray scale pixel light, resulting in the problem of low contrast and poor display quality of the final displayed image. SUMMARY

[0005] The present application aims to solve the technical problems existing in the prior art by providing a projection display system and a projection display device.

[0006] To achieve the above-mentioned purpose, the technical solutions adopted by the embodiments of the present application are as follows:

[0007] In a first aspect, the embodiments of the present application provide a projection display system, which comprises a lens group, a Liquid Crystal on Silicon (LCoS) display panel, a control unit and a lens unit. The lens group at least comprises a linear polarizer and a liquid crystal lens. The control unit is in communication connection with the liquid crystal lens and the LCoS display panel respectively.

[0008] The linear polarizer is used to screen out light beams (e light) of a specific polarization state in the original light and emit the light beams to the liquid crystal lens.

[0009] The liquid crystal lens realizes the deflection of the outgoing light of the low gray scale lens area through the deflection of the liquid crystal molecules, guides the outgoing light of the low gray scale area to the corresponding high gray scale panel area on the LCoS display panel, and realizes the controllable light propagation direction through the deflection of the liquid crystal molecules.

[0010] The control unit is configured to receive a target image to be displayed, perform gray scale identification on the target image to determine a plurality of low gray scale image regions and a plurality of high gray scale image regions in the target image, determine a voltage distribution signal to be applied on each low gray scale lens region corresponding to each low gray scale image region in the liquid crystal lens to control deflection of the liquid crystal molecules, and send pixel information of each gray scale image region to the LCoS display panel.

[0011] The LCoS display panel is configured to modulate outgoing light projected onto a gray scale panel region corresponding to each gray scale image region on the LCoS display panel according to the pixel information of each gray scale image region to obtain modulated light of each gray scale panel region, and project the modulated light of each gray scale panel region to the lens unit.

[0012] The lens unit is configured to magnify the modulated light of each gray scale panel region and project the modulated light onto a screen to form a display image.

[0013] Optionally, the projection display system further comprises a light source module and a polarization beam splitter.

[0014] The light source module is configured to generate the original light and emit the original light to the linear polarizer in the lens group.

[0015] The polarization beam splitter is configured to guide outgoing light of each gray scale lens region in the liquid crystal lens to the LCoS display panel, and project modulated light of each gray scale panel region in the LCoS display panel to the lens unit.

[0016] Optionally, the light source module is a matrix light source module, and the control unit further controls the light source module in real time.

[0017] The control unit is further configured to control the matrix light source module to generate light with different brightnesses in a low gray scale light source region corresponding to each low gray scale image region in the target image according to a position identifier of each low gray scale image region, wherein the light intensity of each low gray scale light source region is determined by a gray scale value of the corresponding low gray scale image region.

[0018] Optionally, the determination of the voltage distribution signal to be applied on each low gray scale lens region corresponding to each low gray scale image region in the liquid crystal lens to control deflection of the liquid crystal molecules comprises:

[0019] determining a linear phase distribution of a low gray scale lens region corresponding to the low gray scale image region in the liquid crystal lens;

[0020] Based on the linear phase distribution of the low grayscale lens region and the pre-constructed voltage and phase response relationship, the linear phase correction voltage distribution signal to be applied to the low grayscale lens region is obtained; by controlling the deflection of liquid crystal molecules to adjust the emission direction of light, the brightness of the high grayscale region is enhanced and the brightness of the low grayscale region is reduced, thereby improving the contrast.

[0021] Optionally, determining the linear phase step distribution of the low grayscale image region corresponding to the low grayscale lens region in the liquid crystal lens includes:

[0022] A phase difference is formed between the upper and lower edges of the low grayscale region;

[0023] Based on the phase difference in the low grayscale region and the preset phase order, a uniformly varying linear phase ladder distribution is sequentially constructed in the low grayscale region, wherein the phase order is 2 or higher.

[0024] Optionally, the deflection of emitted light from the low grayscale lens region through the deflection effect of liquid crystal molecules includes:

[0025] Obtain the pre-constructed relationship between phase difference and deflection angle;

[0026] Based on the phase difference of the low grayscale lens region and the pre-constructed relationship between the phase difference and the deflection angle, the target deflection angle when the e-light of the low grayscale lens region is deflected is determined, and the e-light of the low grayscale lens region is controlled to deflect at the target deflection angle.

[0027] Optionally, the step of modulating the emitted light projected onto the corresponding grayscale panel area on the LCoS display panel based on the pixel information of each of the grayscale image areas to obtain the modulated light of each grayscale panel area includes:

[0028] The voltage signal of each pixel unit in the grayscale panel area is controlled according to the grayscale value of each pixel in the grayscale panel area.

[0029] Based on the voltage signal of each pixel unit on the grayscale panel area, the light projected onto the grayscale panel is modulated to obtain the modulated light of the grayscale panel area.

[0030] Secondly, embodiments of this application also provide a projection display device, which includes the projection display system provided in the first aspect above.

[0031] The beneficial effects of this application are:

[0032] This application provides a projection display system and device. It introduces a linear polarizer and a liquid crystal lens into a traditional projection display system, and combines this with a control unit to identify high-grayscale and low-grayscale regions in the input image in real time, transmitting these regions to the LCoS display panel and the liquid crystal lens respectively. A phase correction voltage is applied to the corresponding low-grayscale lens region in the liquid crystal lens to control the deflection angle of the light beam in that region. This guides the light emitted through the low-grayscale region to the corresponding high-grayscale panel region, reducing the light intensity projected onto the low-grayscale panel region and enhancing the light intensity in the high-grayscale panel region. This effectively reduces the brightness of dark areas in the displayed image, achieving spatial light addressing. This significantly improves the overall dynamic contrast of the displayed image, solving the problem of low contrast and poor display quality caused by the high brightness of low-grayscale pixels in traditional LCoS projection display systems. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the architecture of a traditional projection display system;

[0035] Figure 2 This is a schematic diagram of the structure of a projection display system provided in an embodiment of this application;

[0036] Figure 3 This is a schematic diagram showing the longitudinal deflection of the emitted light from each low grayscale lens region in the liquid crystal lens provided in the embodiment of this application before it is projected onto the LCoS display panel;

[0037] Figure 4 A cross-sectional view of a liquid crystal lens provided in an embodiment of this application;

[0038] Figure 5 A schematic diagram illustrating the working principle of the liquid crystal lens provided in the embodiments of this application;

[0039] Figure 6 This is a schematic diagram showing the light emitted from each low grayscale lens region in the liquid crystal lens provided in the embodiment of this application after lateral deflection and projection onto the LCoS display panel;

[0040] Figure 7 A schematic diagram of the structure of a matrix light source module in another projection display system provided in this application embodiment;

[0041] Figure 8This application provides a schematic diagram of the workflow of a projection display system according to an embodiment of the present application.

[0042] Figure 9 This is a schematic diagram of the workflow of another projection display system provided in an embodiment of this application;

[0043] Figure 10 This is a schematic diagram of the grayscale phase calibration linearity of the liquid crystal lens provided in the embodiments of this application;

[0044] Figure 11 This is a schematic diagram illustrating the workflow of another projection display system provided in an embodiment of this application;

[0045] Figure 12 This is a schematic diagram illustrating the workflow of another projection display system provided in an embodiment of this application;

[0046] Figure 13 A schematic diagram illustrating grayscale brightness calibration of an LCOS display panel provided in an embodiment of this application;

[0047] Figure 14 This is a schematic diagram of the structure of a projection display device provided in an embodiment of this application.

[0048] Icons: 1-Projection display system; 100-Light source module; 101-Light emitting diode; 102-Lens; 120-Matrix light source module; 121-LED matrix; 200-Lens group; 210-Small lens array; 220-Relay lens; 230-Linear polarizer; 240-Liquid crystal lens; 241-Top glass substrate; 242-Top ITO; 243-Top alignment layer; 244-Liquid crystal layer; 245-Bottom alignment layer; 246-Pixel electrode; 247-Bottom glass substrate; 300-Polarization beam splitter; 400-Display system; 410-LCoS display panel; 500-Lens unit; 600-Control unit; 700-Projection display device; 411-Rectangular light spot; 412-Rectangular light distribution. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0050] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0051] First, the background technology involved in this application will be introduced.

[0052] refer to Figure 1 As shown, most current traditional projection display systems use variations of the Kohler lighting system, such as... Figure 1 As shown, the projection display system mainly consists of a light source module 100 (including a light-emitting diode 101 and a lens 102), a lens group 200 (including a small lens array 210 and a relay lens 220), a polarization beam splitter (PBS) 300, a display system 400, an LCoS display panel 410, and a lens unit 500.

[0053] The brightness adjustment of the light source module 100 mainly depends on the power supply control.

[0054] The specific working process is as follows: The light emitted by the light-emitting diode 101 is first shaped and homogenized by the lens 102, and then enters the lens group 200. The small lens array 210 and the relay lens 220 in the lens group 200 further homogenize the light, and then project it onto the display system 400 area through the polarization beam splitter 300, forming a rectangular light spot 411 with a size matching the LCoS display panel 410. After the rectangular light shines on the LCoS display panel 410, the liquid crystal in the LCoS display panel 410 modulates different grayscale information through voltage and reflects the light back to the polarization beam splitter 300. After passing through the polarization beam splitter 300, the image is projected onto the lens unit 500 and magnified for display.

[0055] Therefore, in traditional projection display systems, the generation of the entire dynamic image relies on the reflection modulation of light by the LCoS display panel. However, since the LCoS display panel itself cannot completely shield low-grayscale pixel light, even black areas will retain some brightness, resulting in reduced image contrast. This is especially noticeable when displaying dynamic images, where the brightness of black areas is more pronounced. Therefore, it is urgent to optimize the optical path structure to improve the image quality of projection display systems in dynamic display scenarios.

[0056] To address the aforementioned issues, this application proposes a novel projection display system. This system introduces a linear polarizer and a liquid crystal lens into the traditional projection display system. A control unit identifies high-grayscale and low-grayscale image regions in the input image in real time and applies a phase correction voltage to the corresponding low-grayscale lens region of the liquid crystal lens. This controls the deflection angle of the light beam, deflecting the emitted light from the low-grayscale lens region to the corresponding high-grayscale panel region. This reduces the light intensity projected onto the low-grayscale panel region and enhances the light intensity of the high-grayscale panel region, effectively reducing the dark-field brightness of the displayed image and achieving spatial light addressing. This significantly improves the overall dynamic contrast of the image, solving the problem in existing technologies where the LCoS display panel itself cannot completely shield low-grayscale pixel light, resulting in low contrast in the final displayed image.

[0057] The structure of the projection display system of this application will be described in detail below through several embodiments.

[0058] Optionally, refer to Figure 2 The diagram shown is a structural schematic of a projection display system provided in this application. Figure 2 As shown, the projection display system 1 includes: a lens group 200, an LCoS display panel 410, a lens unit 500, and a control unit 600.

[0059] For example, the control unit 600 can be an electronic device with data processing capabilities.

[0060] The lens group 200 includes at least: a linear polarizer 230 and a liquid crystal lens 240. (Continue to refer to...) Figure 2 As shown, the lens group 200 also includes a small lens array 210 and a relay lens 220.

[0061] The control unit 600 is communicatively connected to the liquid crystal lens 240 and the LCoS display panel 410, respectively, so that the control unit 600 can control the liquid crystal lens 240 and the LCoS display panel 410.

[0062] Linear polarizer 230 is used to filter out the e-ray from the original light and emit the e-ray to liquid crystal lens 240, wherein the e-ray is a beam of light with a specific polarization state. Under the action of linear polarizer 230, only the e-ray (with a specific polarization state) from the original light can enter the liquid crystal lens 240 and undergo spatial deflection therein.

[0063] The control unit 600 is used to receive the target image to be displayed, perform grayscale recognition on the target image to determine multiple high grayscale image regions and multiple low grayscale image regions in the target image, determine the voltage distribution signal to be applied on the low grayscale lens region corresponding to each low grayscale image region in the liquid crystal lens 240, and send the pixel information of each grayscale image region to the LCoS display panel 410.

[0064] The target image is a two-dimensional pixel array, such as an N-row, M-column pixel array.

[0065] To further enhance the visual contrast of an image (i.e., the degree of difference between brightness and darkness in the bright and dark parts of the image, making the image details clearer and more layered), grayscale analysis can be performed on the entire target image, and grayscale recognition can be performed on the target image based on the brightness (grayscale value) of each pixel to obtain multiple grayscale image regions, such as high grayscale image regions and low grayscale image regions.

[0066] High grayscale image areas refer to areas of higher brightness in an image, typically composed of multiple pixels with high grayscale values ​​(e.g., pixel areas that are close to white or have medium to high brightness). These areas may represent brighter objects or backgrounds in the image.

[0067] Low grayscale image areas refer to regions in an image that have lower brightness, consisting of multiple pixels with lower grayscale values ​​(such as pixel areas that are close to black or dark tones), and usually correspond to shadows or dark areas in an image.

[0068] Optionally, this grayscale region division allows for targeted contrast enhancement processing of the two grayscale regions separately. For example, enhancing the local contrast of the low grayscale image region can make the details in the darker areas clearer; while appropriately compressing or optimizing the brightness distribution of the high grayscale image region can prevent overexposure.

[0069] In this application, it is proposed that the voltage distribution signal to be applied to each low grayscale image region in the liquid crystal lens can be determined based on multiple grayscale image regions in the target image, and the pixel information of each grayscale image region (such as the pixel coordinates and pixel values ​​of each pixel in the grayscale image region) can be sent to the LCoS display panel.

[0070] For example, refer to Figure 3 The diagram illustrates how the emitted light from each low-grayscale lens region in the liquid crystal lens is longitudinally deflected and projected onto the LCoS display panel. Specifically, the low-grayscale image region T11 in the target image corresponds to the low-grayscale panel region A11 on the LCoS display panel, and the low-grayscale image region T12 in the target image corresponds to the low-grayscale panel region A13 on the LCoS display panel. The emitted light, originally projected onto the low-grayscale panel regions A11 and A13, is deflected to the adjacent high-grayscale panel region A12.

[0071] The liquid crystal lens 240 is used to deflect the emitted light from the low grayscale lens areas through the deflection effect of liquid crystal molecules, and guide the emitted light generated by each low grayscale lens area to the corresponding high grayscale panel area on the LCoS display panel 410, so as to achieve controllable light propagation direction through the deflection of liquid crystal molecules. Among them, the emitted light generated by each grayscale lens area in the liquid crystal lens 240 forms a rectangular light spot 411 with a size matching that of the LCoS display panel 410.

[0072] The liquid crystal lens has a uniformly distributed square pixel array on its surface. By applying a certain voltage signal to each low grayscale lens area, the liquid crystal molecules are deflected under the action of the voltage signal, so that the light originally projected onto the low grayscale panel area is deflected to the adjacent high grayscale panel area. This achieves the deflection of the outgoing light from the low grayscale lens area, thereby reducing the brightness of dark areas and enhancing the brightness of bright areas, thus improving the dynamic contrast of the image.

[0073] refer to Figure 4 The image shown is a cross-sectional view of the liquid crystal lens provided in this application. Figure 5 This is a schematic diagram illustrating the working principle of a liquid crystal lens; the structure of the liquid crystal lens 240 is as follows. Figure 4 As shown, from top to bottom, the layers are: top glass substrate 241, top ITO 242, top alignment layer 243, liquid crystal layer 244, bottom alignment layer 245, pixel electrode 246, and bottom glass substrate 247. The pixel electrode is a square structure driven by a thin-film transistor (TFT), and the liquid crystal lens 240 can be fabricated using liquid crystal display (LCD) manufacturing processes.

[0074] Preferably, the linear polarizer 230 includes, but is not limited to, a metal linear polarizer, an absorbent polymer polarizer, a lens polarizer, etc., and its polarization direction remains parallel to the initial orientation of the liquid crystal layer 244.

[0075] Preferably, the liquid crystal lens 240 can be manufactured using existing LCD processes, including driving circuitry and liquid crystal layer encapsulation.

[0076] Preferably, the pixels in the liquid crystal lens 240 can be square, rectangular, or other shapes, with a size of 5~40 μm and an aperture ratio of 70~80%.

[0077] Preferably, the pixel electrodes in the liquid crystal lens 240 include, but are not limited to, ITO, to ensure sufficiently high transmittance;

[0078] Preferably, the phase linear correction method of the liquid crystal lens 240 is consistent with the existing correction method for optical communication applications, except that the liquid crystal lens 240 has a higher phase depth and a wider voltage application range.

[0079] Preferably, the liquid crystal used in the liquid crystal lens 240 can be either a positive liquid crystal or a negative liquid crystal. To ensure a higher phase depth, a liquid crystal with a large refractive index and a certain dielectric is required, and the thickness of the liquid crystal layer is designed to be 6~50 μm.

[0080] Preferably, the top alignment layer 243 and the bottom alignment layer 245 of the liquid crystal lens 240 are preferably photoaligned, which can achieve a more uniform liquid crystal arrangement and pretilt angle. Similarly, friction alignment and other methods can be used. The thickness of the alignment layer is not limited, but it is best to meet the requirements of the liquid crystal layer 244.

[0081] Preferably, the liquid crystal lens 240 only changes the amount of light in different areas without changing the rectangular light projected onto the LCoS display panel 410;

[0082] The light deflection principle of the 240-degree liquid crystal lens is as follows: Figure 5 As shown, when the incident parallel e-light passes through the liquid crystal lens, the orientation of the molecules in the liquid crystal layer 244 changes under different voltages (such as V1 to V8), forming a continuous linear phase distribution along the pixel row or column, thereby causing the incident light beam to be deflected at a certain angle when passing through the liquid crystal layer.

[0083] Optionally, in this embodiment, a voltage distribution signal is applied to each low grayscale lens area by the control unit to control the deflection of the liquid crystal molecules and guide the emitted light from each low grayscale lens area to the corresponding designated area (i.e., the high grayscale panel area) on the LCoS display panel, thereby realizing beam deflection control and making the light propagation direction controllable.

[0084] For example, as further referenceFigure 3 As shown, by sequentially setting the pixel rows of the low grayscale lens area corresponding to the low grayscale panel area (such as A11, A13) on the LCoS display panel with voltages that have undergone linear phase correction, the beam can be deflected to the adjacent high grayscale panel area (A12).

[0085] Similarly, refer to Figure 6 The diagram illustrates how light emitted from each low-grayscale lens region in a liquid crystal lens is laterally deflected before being projected onto the LCoS display panel. Light distribution can also be achieved through stepped voltage settings on the vertical pixel columns. For example, by sequentially setting linear phase-corrected voltages on the vertical pixel columns of the low-grayscale lens regions corresponding to the low-grayscale panel regions (such as B11 and B31) on the LCoS display panel, the light beam can be deflected towards the adjacent high-grayscale panel region (B21). After this light deflection process, the light intensity projected onto the low-grayscale panel region is significantly reduced, resulting in a substantial decrease in dark-state brightness, while the high-grayscale panel region receives more luminous flux from adjacent regions, thus enhancing its brightness.

[0086] Therefore, without changing the original optical path structure, this application can achieve orderly deflection of light to a specific area on the LCoS display panel 410 by simply adding a linear polarizer and a liquid crystal lens, and by applying different voltages to each low grayscale lens area in the liquid crystal lens, thereby achieving control of the deflection angle of the light beam and achieving spatial optical addressing effect.

[0087] The LCoS display panel 410 is used to modulate the emitted light on each grayscale panel area according to the pixel information of each grayscale image area to obtain the modulated light of each grayscale panel area, and then project the modulated light of each grayscale panel area onto the lens unit. The pixel information of the grayscale image area includes the pixel coordinates and pixel value of each pixel in the grayscale image area.

[0088] Lens unit 500 is used to magnify the modulated light of each grayscale panel area and form a display image.

[0089] In this embodiment, the LCoS display panel 410 determines the corresponding grayscale panel area on the LCoS display panel 410 based on the pixel information of each grayscale image area. It then applies a voltage to each pixel using the grayscale value of each pixel in the grayscale image area and modulates the emitted light received by the grayscale panel area using the voltage applied to each pixel to obtain modulated light for each grayscale panel area. Finally, it projects the modulated light of the grayscale panel area onto the lens unit to form a display image, thereby achieving a display effect with improved contrast.

[0090] In summary, this application provides a projection display system that introduces a linear polarizer and a liquid crystal lens into a traditional projection display system. A control unit identifies high-grayscale image regions and low-grayscale image regions in the input image in real time, and applies a phase correction voltage to the low-grayscale lens region corresponding to the liquid crystal lens to achieve beam deflection control. This projects the light emitted from the low-grayscale lens region onto the corresponding high-grayscale panel region, reducing the light intensity projected onto the low-grayscale panel region and enhancing the light intensity of the high-grayscale panel region. This effectively reduces the dark-field brightness of the displayed image, achieving spatial light addressing and significantly improving the overall dynamic contrast of the image. This solves the problem in existing LCoS display panel systems where the high brightness of low-grayscale pixels leads to low contrast in the final displayed image.

[0091] refer to Figure 7 The diagram shows that the light source module 100 is a matrix light source module. The matrix light source module 120 is composed of multiple independent and controllable LED units, forming a programmable controllable light source array. Each unit can be individually controlled in terms of brightness and on / off state. It can be combined with three primary color light-emitting diodes to achieve local color control, realize dynamic dimming in space and time, and enhance the contrast of the target area through local illumination to improve the recognition effect.

[0092] In this embodiment, a matrix light source module is proposed as the light source module. The light source module will be explained in detail below through an embodiment.

[0093] refer to Figure 7 As shown, the control unit 600 controls the matrix light source module 120.

[0094] The control unit 600 is also used to control the corresponding low grayscale light source areas on the matrix light source module 120 to generate light of different brightness according to the position markers of each low grayscale area in the target image, wherein the light intensity of each low grayscale light source area is obtained by the grayscale value of the corresponding grayscale area.

[0095] In one feasible way, such as Figure 7 As shown, the matrix light source module 120 (including LED matrix 121 and lens 102) is communicatively connected to the control unit 600.

[0096] After receiving the target image, the control unit 600 performs grayscale processing on the target image and transmits the image containing grayscale levels to the LCoS display panel 410 and the liquid crystal lens 240 respectively. Based on the image being divided into high grayscale and low grayscale zones, the control unit 600 applies a corresponding zone voltage to the liquid crystal lens 240 in the low grayscale region, causing it to deflect the light entering that region, thereby redirecting the light beam passing through the low grayscale lens region to the high grayscale region. Finally, a rectangular light beam with high contrast bright and dark zones is output through the polarization beam splitter 300, and then the image is modulated by the LCoS display panel 410 and projected onto the display screen.

[0097] The matrix light source module 120 can also control the light-emitting units in low grayscale image areas. For example, by appropriately reducing the brightness of LEDs in the low grayscale zones or directly turning off some LED units, the light intensity in that area can be further reduced, thereby achieving brightness suppression at the light source level. Figure 7 The rectangular light distribution 412 behind the lens is shown. This dual control mechanism (i.e., light source modulation and light deflection) further reduces the amount of projected light in low grayscale areas, even approaching zero, while significantly enhancing the light energy in high grayscale areas. Throughout the process, the control unit 600 can continuously perform the above dynamic light control, maintaining high contrast output in the display of consecutive frames of images.

[0098] This application significantly improves the dynamic contrast of the projected image by adding a linear polarizer 230 and a liquid crystal lens 240 between the relay lens 220 and the polarization beam splitter 300, and by combining the active light intensity control of the matrix light source module with the optical deflection function of the liquid crystal lens 240. In particular, when presenting dark scenes, the brightness of the image can be further reduced or even approach zero, meeting the requirements for high-quality image display.

[0099] Therefore, by adopting a matrix light source module structure, precise control of the light source distribution is achieved, thereby forming a dynamic lighting pattern in the target area, improving image recognition accuracy and the energy efficiency of the lighting system.

[0100] The following examples will explain in detail how to deflect the e-light on each low grayscale lens region in a liquid crystal lens.

[0101] Optionally, refer to Figure 8 As shown, the above-described method for determining the voltage distribution signal to be applied to each low grayscale image region on each corresponding low grayscale lens region in the liquid crystal lens to control the deflection of the liquid crystal molecules includes:

[0102] S1001. Determine the linear phase distribution of the low grayscale image region in the liquid crystal lens corresponding to the low grayscale lens region.

[0103] S1002. Based on the linear phase distribution of the low grayscale lens region and the pre-constructed voltage-phase response relationship, obtain the linear phase correction voltage distribution signal to be applied to the low grayscale lens region.

[0104] In the low grayscale lens region, the phase at adjacent positions changes linearly and uniformly, and the phase at each position is linearly related to the voltage to be applied.

[0105] The relationship between voltage and phase response can be established by experimentally measuring the phase output under different voltages and creating a "voltage vs. phase" response curve. Therefore, by monitoring the phase in real time, the voltage distribution signal applied to the low-grayscale lens region can be adjusted, achieving high-precision control over the propagation direction of e-light received in the low-grayscale lens region.

[0106] In one feasible approach, it is proposed to calculate the linear phase correction voltage signal at each position based on the phase of the low grayscale image region at each position on the low grayscale lens region corresponding to the low grayscale lens region in the liquid crystal lens and the pre-constructed "voltage and phase" response curve, thereby obtaining the linear phase correction voltage distribution signal to be applied on the low grayscale lens region.

[0107] Optionally, refer to Figure 9 As shown, step S1001 above includes:

[0108] S1101, A phase difference is formed between the upper edge phase angle and the lower edge phase angle in the low grayscale lens region.

[0109] S1102. Based on the phase difference in the low grayscale lens region and the preset phase order, a uniformly varying linear phase ladder distribution is constructed sequentially in the low grayscale lens region.

[0110] Among them, the phase order is 2 or higher, with a lower example being 3.

[0111] In one feasible way, continue to refer to Figure 5 As shown, the phase angle of the upper edge of the low grayscale lens region is and the lower edge phase angle is The difference between the phase angle of the upper edge and the phase angle of the lower edge can be calculated as follows: ,Right now Then, based on a preset phase order (e.g., 3rd order), a uniformly varying linear phase step distribution is constructed sequentially in the low grayscale lens region. This ensures that the phase at adjacent positions in the low grayscale lens region is uniformly distributed in a step, thereby achieving continuous deflection of the liquid crystal rotation angle, and the deflection angle is always... θ .

[0112] Optionally, refer to Figure 10As shown, this illustrates the correspondence between phase and grayscale. That is, after determining the low grayscale region, the phase distribution of each pixel in the grayscale region can be obtained based on the phase of each pixel in the grayscale region and the correspondence between phase and grayscale.

[0113] Optionally, refer to Figure 11 As shown, the above steps include:

[0114] S1301. Obtain the pre-constructed relationship between phase difference and deflection angle.

[0115] S1302. Based on the phase difference of the low grayscale lens region and the pre-constructed relationship between the phase difference and the deflection angle, determine the target deflection angle when the e-light in the low grayscale lens region deflects, and control the e-light in the low grayscale lens region to deflect at the target deflection angle.

[0116] The pre-established relationship between the phase difference and the deflection angle is shown in the following formula (1):

[0117] (1)

[0118] in, The wavelength of the deflected light, This is used to implement the length of the optical deflection unit (such as the length of the A11 region).

[0119] In this embodiment, the target deflection angle when the e-ray in the low grayscale lens region is deflected can be obtained by utilizing the phase difference of the low grayscale lens region and the above formula (1). And control the e-ray in the low grayscale lens area to deflect at the target angle. Deflect.

[0120] It should be noted that by selecting those with greater... Liquid crystal or increasing the thickness of the liquid crystal layer This can effectively increase the adjustable phase difference of the liquid crystal lens. The theoretical model is shown in the following formula (2):

[0121] (2)

[0122] Therefore, the adjustable phase difference range and the length of the low grayscale lens region can be used to achieve this. It can achieve a precise deflection angle of light, causing the light to be directed towards a designated area.

[0123] Optionally, refer to Figure 12 As shown, the above steps modulate the emitted light projected onto the corresponding grayscale panel area on the LCoS display panel based on the pixel information of each grayscale image area, to obtain the modulated light for each grayscale panel area, including:

[0124] S1401. Control the voltage signal of each pixel unit on the grayscale panel area according to the grayscale value of each pixel in the grayscale image area.

[0125] S1402. Based on the voltage signal of each pixel unit, the emitted light projected onto the grayscale panel area is modulated to obtain the modulated light of the grayscale panel area.

[0126] The position identifier in the grayscale image region is the pixel coordinate of each pixel in the grayscale image region.

[0127] In one feasible approach, the pixel coordinates of each pixel in the grayscale image region can be used to determine the corresponding grayscale panel region on the LCoS display panel. Simultaneously, the voltage signals of multiple pixel units corresponding to the grayscale panel region can be controlled based on the grayscale values ​​of each pixel in the grayscale image region. For example, the larger the grayscale value of a pixel, the larger the voltage signal of the pixel unit corresponding to that pixel. The voltage signals of multiple pixel units are used to modulate the deflected light incident on the grayscale panel region to obtain the modulated light of the grayscale panel region.

[0128] Among them, reference Figure 13 As shown, the relationship between LCoS modulation grayscale and brightness is in the range of Gamma 2.2±0.2. When projected onto the image through the lens unit 500, it can achieve the effect of low grayscale approaching black field and high grayscale brightness enhancement in the output image, thereby significantly improving the dynamic contrast of the overall image.

[0129] Optionally, refer to Figure 14 This application also provides a projection display device 700, which includes the projection display system 1 provided in the above embodiments.

[0130] In one feasible approach, the projection display device 700 provided in this application can be used to achieve the effect of low grayscale approaching black field and high grayscale brightness enhancement in the output image, thereby significantly improving the dynamic contrast of the overall image.

[0131] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A projection display system, characterized in that, include: The system includes a linear polarizer, a liquid crystal lens, a control unit, an LCoS display panel, and a lens unit, wherein the control unit is communicatively connected to the liquid crystal lens and the LCoS display panel, respectively. The linear polarizer is used to filter out the e-beam of a specific polarization state in the original light and emit the beam to the liquid crystal lens; The liquid crystal lens deflects the light emitted from the low grayscale lens area through the deflection of liquid crystal molecules, guiding the light emitted from the low grayscale area to the corresponding high grayscale panel area on the LCoS display panel, so that the direction of light propagation can be controlled through the deflection of liquid crystal molecules. The control unit is used to receive the target image to be displayed, perform grayscale recognition on the target image to determine multiple low grayscale image regions and multiple high grayscale image regions in the target image, and determine the voltage distribution signal to be applied to each low grayscale lens region corresponding to each low grayscale image region in the liquid crystal lens, so as to control the deflection of the liquid crystal molecules, and send the pixel information of each grayscale image region to the LCoS display panel. The LCoS display panel is used to modulate the emitted light projected onto the corresponding grayscale panel area on the LCoS display panel according to the pixel information of each grayscale image region, to obtain the modulated light of each grayscale panel area, and to project the modulated light of each grayscale panel area onto the lens unit. The lens unit is used to magnify the modulated light of each grayscale panel area and project it onto the screen to form a display image.

2. The system according to claim 1, characterized in that, The projection display system also includes: a light source module and a polarization beam splitter; The light source module is used to generate the original light and emit the original light to the linear polarizer; The polarization beam splitter is used to guide the outgoing light from each grayscale lens region in the liquid crystal lens onto the LCoS display panel; and to project the modulated light from each grayscale panel region in the LCoS display panel onto the lens unit.

3. The system according to claim 2, characterized in that, When the light source module is a matrix light source module, the control unit also controls the light source module; The control unit is further configured to control the corresponding low grayscale light source regions on the matrix light source module to generate light of different brightness according to the position identifiers of each of the low grayscale image regions in the target image, wherein the light intensity of each of the low grayscale light source regions is obtained from the grayscale value of the corresponding low grayscale image region.

4. The system according to claim 1, characterized in that, The control unit applies voltage distribution signals to the corresponding low grayscale lens regions in the liquid crystal lens according to the low grayscale image region, in order to control the deflection of the liquid crystal molecules, including: Determine the linear phase distribution of the low grayscale image region corresponding to the low grayscale lens region in the liquid crystal lens; Based on the linear phase distribution of the low grayscale lens region and the pre-constructed voltage-phase response relationship, the linear phase correction voltage distribution signal to be applied to the low grayscale lens region is obtained. By controlling the deflection of liquid crystal molecules to adjust the direction of light emission, the brightness of high grayscale areas is enhanced and the brightness of low grayscale areas is reduced, thereby improving contrast.

5. The system according to claim 4, characterized in that, Determining the linear phase distribution of the low grayscale image region corresponding to the low grayscale lens region in the liquid crystal lens includes: A phase difference is formed between the upper and lower edges of the low grayscale lens region; Based on the phase difference in the low grayscale lens region and the preset phase order, a uniformly varying linear phase ladder distribution is sequentially constructed in the low grayscale lens region, wherein the phase order is 2 or higher.

6. The system according to claim 5, characterized in that, The method of deflecting the emitted light from the low grayscale lens region through the deflection effect of liquid crystal molecules includes: Obtain the pre-constructed relationship between phase difference and deflection angle; Based on the phase difference of the low grayscale lens region and the pre-constructed relationship between the phase difference and the deflection angle, the target deflection angle when the e-light of the low grayscale lens region is deflected is determined, and the e-light of the low grayscale lens region is controlled to deflect at the target deflection angle.

7. The system according to claim 1, characterized in that, The step of modulating the emitted light projected onto the corresponding grayscale panel area on the LCoS display panel based on the pixel information of each grayscale image area to obtain the modulated light of each grayscale panel area includes: The voltage signal of each pixel unit in the grayscale panel area is controlled according to the grayscale value of each pixel in the grayscale panel area. Based on the voltage signal of each pixel unit on the grayscale panel area, the emitted light projected onto the grayscale panel is modulated to obtain the modulated light of the grayscale panel area.

8. A projection display device, characterized in that, The projection display device includes the projection display system described in any one of claims 1-7.

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