Projection display device
By introducing a multiplexed design of the reflection adjustment module and the projection lens into the projection display device, the problem of high power consumption in some application scenarios of traditional projection display devices is solved, and the effect of reducing power consumption and flattening of the structure is achieved.
Patent Information
- Application Number
- CN202421400193.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-18
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-06-18
AI Technical Summary
In some application scenarios, the beam emitted by the light source cannot be effectively utilized by the display panel, resulting in high power consumption.
A projection display device is designed, including a light source module, a reflection adjustment module, a projection lens and a light modulation module. The light beam propagation direction is adjusted by the reflection adjustment module, and different areas on the light modulation module are controlled to be illuminated by the light beam emitted by the light source module at different moments, ensuring that the light beam can illuminate the entire light modulation module and reduce the device volume through the multiplexing of the projection lens.
It is realized that the device power consumption is reduced during the partition lighting of the light modulation module, and the overall structure of the projection display device is flattened through structural optimization, which is convenient for the installation and use of the near-eye display device.
Smart Images
Figure CN222600046U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of projection display technology, and in particular to a projection display device. Background Art
[0002] In the projection display scenario, for some typical application scenarios such as information prompts and navigation, the displayed content only occupies a part of the display area, so that in the traditional projection display device, part of the light beam emitted by the light source cannot be used by the display panel during the projection display process, resulting in high power consumption of the projection display device. Utility Model Content
[0003] The projection display device provided in the embodiment of the present application includes: a light source module, which is used to emit a light beam; a reflection adjustment module, which is arranged in the light emitting direction of the light source module, and is used to adjust the propagation direction of the light beam emitted by the light source module, so as to control different areas on the light modulation module to be irradiated by the light beam emitted by the light source module at different times; a projection lens, which is arranged between the reflection adjustment module and the light modulation module, and is used to adjust the projection direction of the light beam emitted by the reflection adjustment module, so as to project the light beam with the adjusted projection direction to the light modulation module; the light modulation module is used to modulate the projected light beam and output the modulated image light to the projection lens, and the image light is used to be projected by the projection lens to the area to be displayed to form a projection image.
[0004] Optionally, the reflection adjustment module adjusts the adjustment frequency of the light beam propagation direction in the fast axis direction of the light beam emitted by the light source module to a first frequency, and adjusts the adjustment frequency of the light beam propagation direction in the slow axis direction of the light beam emitted by the light source module to a second frequency, so as to control the illumination area of the light beam projected onto the light modulation module to move sequentially on the light modulation module according to multiple target movement trajectories, wherein the fast axis direction is parallel to the first side of the light modulation module, the slow axis direction is parallel to the second side of the light modulation module, and the length of the first side is greater than the length of the second side.
[0005] Optionally, the relative distance between adjacent target moving trajectories is negatively correlated with the first frequency and the second frequency, and the size of a single illumination area of the light beam projected onto the light modulator module on the light modulator module is positively correlated with the size of the divergence angle of the light beam projected onto the light modulator module; within the time when the projection display device displays a frame of projection image, after the illumination area of the light beam projected onto the light modulator module moves sequentially on the light modulator module according to the multiple target moving trajectories, the area composed of the multiple illumination areas covers the light modulator module.
[0006] Optionally, the first frequency matches the resonant frequency of the reflection adjustment module, the second frequency matches the refresh rate of the projected image, the reflection adjustment module is used to control the illumination area of the light beam projected onto the light modulation module to move row by row on the light modulation module, the first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 30 Hz and less than 500 Hz.
[0007] Optionally, both the first frequency and the second frequency match the resonant frequency of the reflection adjustment module, and the reflection adjustment module is used to control the simple harmonic movement of the illumination area of the light beam projected onto the light modulation module on the light modulation module. The first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 200 Hz and less than 5,000 Hz.
[0008] Optionally, the projection display device further comprises a first collimating lens, which is disposed between the light source module and the reflection adjustment module, and is used for collimating the light beam emitted by the light source module and then emitting the light beam to the reflection adjustment module.
[0009] Optionally, the projection display device also includes a scattering module, which is arranged in the light emitting direction of the reflection adjustment module, and the scattering module is used to adjust the divergence angle of the collimated light beam and then emit it so that it is emitted to the light modulation module at a first divergence angle, wherein the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
[0010] Optionally, the projection display device also includes a light reflection module; the light reflection module is arranged in the light emitting direction of the reflection adjustment module, and the light reflection module is used to reflect the collimated light beam to the scattering module; the scattering module is used to adjust the divergence angle of the light beam reflected by the light reflection module so that it is emitted to the light modulation module at the first divergence angle.
[0011] Optionally, the light source module is located beside the projection lens.
[0012] Optionally, the projection display device also includes a second collimating lens, which is arranged between the light source module and the light modulation module; the second collimating lens is used to adjust the divergence angle of the target light beam and then emit it so that it is emitted to the light modulation module at a first divergence angle, and the target light beam is the light beam emitted by the light source module or the light beam reflected by the reflection adjustment module, wherein the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
[0013] Optionally, the position of the second collimating lens relative to the light source module is movable, and the divergence angle of the light beam projected to the light modulation module is positively correlated with a first distance, which is a relative distance between the focus of the second collimating lens and the light source module.
[0014] Optionally, the projection display device also includes a waveguide, which is arranged in the light output direction of the projection lens, and the waveguide and the reflection adjustment module are arranged on the same side of the projection lens; the waveguide is used to perform total reflection transmission on the image light to project the image light to the area to be displayed to form the projection image.
[0015] In the projection display device provided by the present application, a reflection adjustment module is provided to adjust the propagation direction of the light beam emitted by the light source module. The reflection adjustment module controls different areas on the light modulation module to be irradiated by the light beam emitted by the light source module at different times, thereby ensuring that the light beam emitted by the light source module can illuminate the entire light modulation module, so that the light beam emitted by the light source module can only illuminate a part of the light modulation module at a time, thereby achieving a reduction in the power consumption of the device in the process of zoned lighting of the light modulation module. In addition, the light beam in the projection display device passes through the projection lens twice. Through the reuse of the projection lens, the volume of the projection display device is reduced, and the overall structure of the projection display device is flattened, which is beneficial to its installation and use in near-eye display devices.
[0016] These and other aspects of the present application will become more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.
[0018] Figure 1 A schematic structural diagram of a projection display device provided in one embodiment of the present application is shown.
[0019] Figure 2 A schematic structural diagram of a projection display device provided in another embodiment of the present application is shown.
[0020] Figure 3 A schematic diagram of multiple target movement trajectories of an illumination area of a light beam on a light modulation module provided by an embodiment of the present application is shown.
[0021] Figure 4 A schematic diagram of multiple target movement trajectories of an illumination area of a light beam on a light modulation module provided in another embodiment of the present application is shown.
[0022] Figure 5 A schematic structural diagram of a projection display device provided in yet another embodiment of the present application is shown.
[0023] Figure 6 A schematic structural diagram of a projection display device provided in yet another embodiment of the present application is shown. DETAILED DESCRIPTION
[0024] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.
[0025] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.
[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0027] Please refer to Figure 1 , Figure 1 The structure diagram of the projection display device 1 provided by an embodiment of the present application is shown below. Figure 1 The projection display device 1 provided in the embodiment of the present application is described in detail. Figure 1 As shown, the projection display device 1 at least includes a light source module 10 , a reflection adjustment module 20 , a projection lens 30 and a light modulation module 40 .
[0028] In this embodiment, the reflection adjustment module 20 is arranged in the light emitting direction of the light source module 10. After the light source module 10 emits a light beam, the reflection adjustment module 20 is used to adjust the propagation direction of the light beam emitted by the light source module 10, so as to control different areas on the light modulation module 40 to be illuminated by the light beam emitted by the light source module 10 at different times. The light modulation module 40 includes a plurality of pixel units distributed in an array. When the reflection adjustment module 20 adjusts the propagation direction of the light beam emitted by the light source module 10, the light beam emitted by the light source module 10 is reflected by the reflection adjustment module 20 to the light modulation module 40, and a single illumination area of the light beam on the light modulation module 40 is much smaller than the light modulation module 40. The light beam is used to illuminate the pixel units in the current illumination area on the light modulation module 40.
[0029] Furthermore, the projection lens 30 is disposed between the reflection adjustment module 20 and the light modulation module 40 , and is used to adjust the projection direction of the light beam emitted by the reflection adjustment module 20 , so as to project the light beam with the adjusted projection direction to the light modulation module 40 .
[0030] In this embodiment, when the reflection adjustment module 20 controls the light beam emitted by the light source module 10 to irradiate different areas on the light modulation module 40 at different times, the light modulation module 40 is also used to modulate the light beam reflected by the reflection adjustment module 20 and projected onto the light modulation module 40 through the projection lens 30, and output the modulated image light, which is used to project to the area to be displayed to form a projection image.
[0031] In an embodiment of the present application, a reflection adjustment module 20 is provided to adjust the propagation direction of the light beam emitted by the light source module 10. The reflection adjustment module 20 controls different areas on the light modulation module 40 to be irradiated by the light beam emitted by the light source module 10 at different times, thereby ensuring that the light beam emitted by the light source module 10 can illuminate the entire light modulation module 40, so that the light beam emitted by the light source module 10 can only illuminate a partial area on the light modulation module 40 at a time, thereby achieving a reduction in the power consumption of the device in the process of partitioning the light modulation module 40; and, in the projection display device 1, the light beam passes through the projection lens 30 twice. Through the reuse of the projection lens 30, the volume of the projection display device 1 is reduced, so that the overall structure of the projection display device 1 is flattened, which is beneficial to its installation and use in a near-eye display device.
[0032] Please refer to Figure 2 , Figure 2 FIG. 2 shows a schematic diagram of the structure of a projection display device provided by another embodiment of the present application. Figure 2 As shown, the projection display device at least includes a light source module 10 , a reflection adjustment module 20 , a projection lens 30 and a light modulation module 40 .
[0033] In this embodiment, after the light source module 10 emits a light beam, when the reflection adjustment module 20 adjusts the propagation direction of the light beam emitted by the light source module 10, in the fast axis direction of the light beam emitted by the light source module 10, the adjustment frequency of the light beam propagation direction adjusted by the reflection adjustment module 20 is a first frequency, and in the slow axis direction of the light beam emitted by the light source module 10, the adjustment frequency of the light beam propagation direction adjusted by the reflection adjustment module 20 is a second frequency, so as to control the illumination area of the light beam projected to the light modulation module 40 to move sequentially according to multiple target movement tracks on the light modulation module 40. Among them, the fast axis direction is parallel to the first side of the light modulation module 40, the slow axis direction is parallel to the second side of the light modulation module 40, and the length of the first side is greater than the length of the second side.
[0034] Optionally, the reflection adjustment module 20 may be a two-dimensional scanning mirror, the mirror surface of which may be deflected in two dimensions, so that the two-dimensional scanning mirror may adjust the propagation direction of the light beam simultaneously along the fast axis direction and the slow axis direction of the light beam emitted by the light source module 10. Thus, during the deflection of the mirror surface of the two-dimensional scanning mirror, when the light beam emitted by the light source module 10 is reflected by the two-dimensional scanning mirror and then projected onto the light modulation module 40, the light beam may perform a two-dimensional scan on the light modulation module 40, that is, scan the light modulation module 40 simultaneously along the fast axis direction parallel to the first side of the light modulation module 40 and the slow axis direction parallel to the second side of the light modulation module 40.
[0035] In this embodiment, the light modulation module 40 can be a liquid crystal display (LCD), a digital micromirror device (DMD) or a liquid crystal on silicon (LCOS), which is not limited here. Among the multiple pixel units arrayed on the light modulation module 40, each pixel unit can independently modulate the light beam irradiated thereon, thereby modulating the grayscale, color and other information of the final projection image. In addition, the grayscale modulation mode of the light modulation module 40 is amplitude modulation. The light modulation module 40 keeps the light intensity modulation amplitude of each pixel unit unchanged within a single scanning cycle of the reflection adjustment module 20 (i.e., the time for the projection display device to display a frame of projection image). When the illumination area of the light beam is controlled by the reflection adjustment module 20 to move on the light modulation module 40, the control module dynamically adjusts the illumination intensity of the light beam emitted by the light source module 10, so as to achieve accurate pixel-level grayscale modulation.
[0036] Optionally, a control module (not shown) is further provided in the projection display device 1, and the control module is respectively connected to the light source module 10, the reflection adjustment module 20 and the light modulation module 40, and the control module is used to determine the target display light intensity of the target area on the light modulation module 40 according to the projection image to be displayed, and the target display light intensity is the maximum display light intensity among the display light intensities corresponding to the pixel units of the target area, so that when the reflection adjustment module 20 controls the target area on the light modulation module 40 to be illuminated by the light beam emitted by the light source module 10, the illumination light intensity of the light beam emitted by the light source module 10 is controlled to match the target display light intensity.
[0037] In this embodiment, the size of the target area matches the size of the unit illumination area of the light beam emitted by the light source module 10 on the light modulation module 40 after the light beam is reflected by the reflection adjustment module 20. Since the target display light intensity corresponding to the target area is the maximum display light intensity among the display light intensities corresponding to the pixel units of the target area, the maximum display light intensities corresponding to different areas on the light modulation module 40 are different. Therefore, in the process in which the reflection adjustment module 20 controls the light beam emitted by the light source module 10 to illuminate different areas on the light modulation module 40 at different times, the illumination light intensity of the light beam emitted by the light source module 10 is controlled by the control module to match the target display light intensity corresponding to the target area, so that after the illumination light intensity of the light beam emitted by the light source module 10 is dynamically adjusted by the control module, the light source module 10 does not need to use a light beam with a larger light intensity to illuminate the entire area of the light modulation module 40, thereby reducing the power consumption of the projection display device.
[0038] For example, in a partial projection display scenario, the display screen only occupies a partial area of the projection image, and the remaining partial area of the projection image is not displayed. When the target area is located in the partial area on the light modulation module 40 where the image is not displayed, if the display screen corresponding to the target area is a black image, so that the reflection adjustment module 20 controls the light source module 10 to emit a light beam to irradiate the target area, the control module controls the light source module 10 to stop emitting the light beam or reduce the illumination intensity of the light beam emitted. Based on this, the reflection adjustment module 20 enables the light beam emitted by the light source module 10 to illuminate only a partial area on the light modulation module 40 each time. When the reflection adjustment module 20 controls the illumination area of the light beam emitted by the light source module 10 to move on the light modulation module 40 to ensure that the light beam emitted by the light source module 10 can illuminate the entire light modulation module 40, the illumination intensity of the light beam emitted by the light source module 10 is dynamically adjusted by the control module, and the light source module 10 does not need to use a light beam with a larger light intensity to irradiate the entire area of the light modulation module 40, thereby reducing the power consumption of the projection display device.
[0039] For example, for the pixel unit A on the light modulation module 40, when the reflection adjustment module 20 controls the target area where the pixel unit A on the light modulation module 40 is located to be illuminated, the control module controls the illumination intensity of the light beam emitted by the light source module 10 to match the target display intensity I of the target area where the pixel unit A is located, and the light intensity modulation coefficient of the light modulation module 40 at the pixel unit A is λ, then the final display intensity IA of the pixel unit A is:
[0040] IA = λI;
[0041] Among them, if the display light intensity corresponding to the pixel unit A is the maximum display light intensity among the display light intensities corresponding to the pixel units in the target area where the pixel unit A is located, then λ is 1, and the final display light intensity IA of the pixel unit A matches the target display light intensity I of the target area where the pixel unit A is located. In addition, since the brightness perceived by the human eye is not linearly related to the actual display brightness of the display panel, the human eye is more sensitive to changes in brightness in a low-brightness environment, and vice versa in a high-brightness environment, which is called the gamma characteristic. When the light modulation module 40 drives each pixel unit, it is also necessary to perform gamma correction on each pixel unit. After gamma correction, the grayscale corresponding to each pixel unit can be obtained, thereby ensuring that the human eye can obtain a uniformly changing brightness perception to adapt to the gamma characteristics of the human eye.
[0042] It should be noted that the two-dimensional scanning mirror at least includes actuators such as Micro Electro Mechanical System (MEMS) and Voice Coil Actuator (VCM), and the driving mode of the two-dimensional scanning mirror can at least be electrostatic drive, electromagnetic drive or piezoelectric drive, which is not limited here. Among them, the micro-electromechanical system can integrate multiple sensors or actuators with different functions, different sensitive directions or actuation directions into one, and it has the advantages of small size, light weight, low energy consumption, small inertia and short response time when used in a projection display device; the voice coil motor is a device that converts electrical energy into mechanical energy, which can control the light source to move in a linear and limited swing angle, and is used for small stroke, high speed, high acceleration movement, and can be used in a small space. It also has the advantages of small size, low energy consumption and short response time when used in the projection display device in this application.
[0043] In this embodiment, during the time when the projection display device displays a frame of projection image, the propagation direction of the light beam is adjusted simultaneously in the fast axis direction and the slow axis direction of the light beam through the reflection adjustment module 20, so as to control the illumination area of the light beam projected to the light modulation module 40 to move sequentially according to multiple target movement tracks on the light modulation module 40. Among them, the relative distance between adjacent target movement tracks is negatively correlated with the first frequency and the second frequency, and the size of a single illumination area of the light beam projected to the light modulation module 40 on the light modulation module 40 is positively correlated with the divergence angle of the light beam projected to the light modulation module 40. The division of the area to be illuminated corresponding to the multiple pixel units on the light modulation module 40 should ensure that there is a target movement track passing through each area to be illuminated, and the size of a single area to be illuminated on the light modulation module 40 is determined by the relative distance between adjacent target movement tracks when the illumination area of the light beam moves on the light modulation module 40.
[0044] Optionally, the first frequency and the second frequency are adjusted to adjust the relative distance between adjacent target moving tracks, and the divergence angle of the light beam projected to the light modulation module 40 is adjusted to adjust the size of a single illumination area on the light modulation module 40, so that after the illumination area of the light beam projected to the light modulation module 40 moves sequentially on the light modulation module 40 according to the multiple target moving tracks, the area composed of the multiple illumination areas covers the light modulation module 30, thereby achieving uniform illumination of the light modulation module 30. For example, when the first frequency and / or the second frequency increases and the relative distance between adjacent target moving tracks decreases, the size of the single illumination area is reduced by reducing the divergence angle of the light beam projected to the light modulation module 40, thereby increasing the number of areas to be illuminated divided on the light modulation module 40; when the first frequency and / or the second frequency decreases and the relative distance between adjacent target moving tracks increases, the size of the single illumination area is increased by increasing the divergence angle of the light beam projected to the light modulation module 40, thereby reducing the number of areas to be illuminated divided on the light modulation module 40.
[0045] As an implementation method, Figure 3 As shown, Figure 3A schematic diagram of multiple target movement trajectories of the illumination area of the light beam on the light modulation module 40 provided in an embodiment of the present application is shown. In this embodiment, the first frequency matches the resonant frequency of the reflection adjustment module, and the second frequency matches the refresh rate of the projected image. Among them, the first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 30 Hz and less than 500 Hz; at this time, preferably, when the divergence angle of the light beam projected to the light modulation module 40 is greater than 0.5 degrees and less than 5 degrees, a relatively good lighting effect can be achieved; for example, when the first frequency is 1000 Hz and the second frequency is 100 Hz, the divergence angle of the light beam projected to the light modulation module 40 is preferably 4.0 degrees-4.5 degrees; when the first frequency is 15,000 Hz and the second frequency is 400 Hz, the divergence angle of the light beam projected to the light modulation module 40 is preferably 1.0 degrees-1.5 degrees, and there is no limitation here.
[0046] Optionally, the reflection adjustment module is used to control the illumination area of the light beam emitted by the light source module to move row by row on the light modulation module 40. The reflection adjustment module adopts a raster scanning method, and in the fast axis direction of the light beam emitted by the light source module, the adjustment frequency of the light beam propagation direction adjusted by the reflection adjustment module matches the resonant frequency of the reflection adjustment module, so as to obtain a larger scanning gain, achieve a larger scanning angle or lower scanning power consumption; in the slow axis direction of the light beam emitted by the light source module, the adjustment frequency of the light beam propagation direction adjusted by the reflection adjustment module matches the refresh rate of the projected image, for example, when the projected image is monochrome, the second frequency is 60Hz, and when the projected image is RGB sequential display, the second frequency is 180Hz. In this way, within the time when the projection display device displays a frame of projection image, the area composed of the illumination area of the light beam moving row by row covers the light modulation module 40.
[0047] Among them, since the fast axis direction is parallel to the first side of the light modulator module 40, and the fast axis direction is parallel to the second side of the light modulator module 40, the reflection adjustment module controls the illumination area of the light beam emitted by the light source module to be scanned simultaneously along the first side and the second side of the light modulator module 40, which is beneficial to divide the illumination area for multiple pixel units on the light modulator module 40.
[0048] As an implementation method, Figure 4 As shown, Figure 4A schematic diagram of multiple target movement trajectories of the illumination area of the light beam on the light modulation module 40 provided in another embodiment of the present application is shown. In this embodiment, both the first frequency and the second frequency match the resonant frequency of the reflection adjustment module. Among them, the first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 200 Hz and less than 5,000 Hz; at this time, preferably, when the divergence angle of the light beam projected to the light modulation module 40 is greater than 0.5 degrees and less than 5 degrees, a relatively good lighting effect can be achieved; for example, when the first frequency is 600 Hz and the second frequency is 400 Hz, the divergence angle of the light beam projected to the light modulation module 40 is preferably 4.0 degrees-4.5 degrees; when the first frequency is 15,000 Hz and the second frequency is 4,000 Hz, the divergence angle of the light beam projected to the light modulation module 40 is preferably 1.0 degrees-1.5 degrees, and there is no limitation here.
[0049] Optionally, the reflection adjustment module is used to control the illumination area of the light beam emitted by the light source module to move harmonically on the light modulation module 40. The reflection adjustment module adopts a Lissajous scanning method, and in the fast axis direction and the slow axis direction of the light beam emitted by the light source module, the adjustment frequency of the reflection adjustment module to adjust the propagation direction of the light beam matches the resonant frequency of the reflection adjustment module, that is, the scanning frequency of the illumination area of the light beam controlled by the reflection adjustment module on the entire light modulation module 40 is the greatest common divisor of the fast axis scanning frequency and the slow axis scanning frequency, the reflection adjustment module works in a resonant state in both the fast axis direction and the slow axis direction, and the driving power consumption of the reflection adjustment module is low. In this way, within the time when the projection display device displays a frame of projection image, the area composed of the illumination area of the harmonically moving light beam covers the light modulation module 40.
[0050] Among them, when the reflection adjustment module controls the illumination area of the light beam emitted by the light source module to scan simultaneously along the first side and the second side of the light modulation module 40, under the strategy of simple harmonic movement of the illumination area of the light beam controlled by the reflection adjustment module on the light modulation module 40, the division of the areas to be illuminated corresponding to the multiple pixel units on the light modulation module 40 should ensure that there is a moving trajectory passing through each area to be illuminated.
[0051] In this embodiment, the projection display device also includes a first collimating lens 50, which is arranged between the light source module 10 and the reflection adjustment module 20. The first collimating lens 50 is used to collimate the light beam emitted by the light source module 10 and project the collimated light beam to the reflection adjustment module 20.
[0052] Optionally, the projection display device also includes a scattering module 60, which is arranged in the light emitting direction of the reflection adjustment module 20. The scattering module 60 is used to adjust the divergence angle of the collimated light beam and then emit it so that it is emitted to the light modulation module 40 at a first divergence angle, wherein the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
[0053] In this embodiment, the projection display device further includes a waveguide 70, which is arranged in the light emitting direction of the light modulation module 40, and the waveguide 70 and the reflection adjustment module 20 are arranged on the same side of the projection lens 30; the projection lens 30 is also used to adjust the divergence angle of the image light before emitting, and the divergence angle of the image light increases after the angle adjustment; the waveguide 70 is used to perform total reflection transmission on the image light to project the image light to the area to be displayed to form a projection image. In this way, the light beam in the projection display device passes through the projection lens 30 twice, and the volume of the projection display device is reduced by multiplexing the projection lens 30, and the arrangement of the waveguide 70 and the multiplexed projection lens 30 makes the overall structure of the projection display device flat, which is conducive to its installation and use in the near-eye display device.
[0054] Optionally, after the waveguide 70 performs total reflection transmission on the image light, the image light can be projected onto a projection display screen to form a projection image on the projection display screen. The waveguide 70 can also project the image light to the human eye. After the image light enters the human eye, a projection image can be formed on the retina. There is no limitation here.
[0055] In this embodiment, the reflection adjustment module 20 is set to adjust the propagation direction of the light beam emitted by the light source module 10 in both the fast axis direction and the slow axis direction, so that the light beam emitted by the light source module 10 can be two-dimensionally scanned on the light modulation module 40, ensuring that the light beam emitted by the light source module 10 can illuminate the entire light modulation module 40. In addition, when the reflection adjustment module 20 controls the illumination area of the light beam to move on the light modulation module 40, the illumination intensity of the light beam emitted by the light source module 10 is controlled to match the maximum display intensity among the display intensity corresponding to the pixel unit of the target area illuminated by it, so that in the process of dynamically adjusting the illumination intensity of the light beam emitted by the light source module 10, accurate pixel-level grayscale modulation can be achieved on the light modulation module 40, ensuring that the human eye can obtain a uniformly changing brightness perception, and there is no need to use a light beam with a larger light intensity for irradiation of the entire area of the light modulation module 40, thereby reducing the power consumption of the projection display device.
[0056] Please refer to Figure 5 , Figure 5 FIG. 2 shows a schematic diagram of the structure of a projection display device provided by another embodiment of the present application. Figure 5As shown, the projection display device at least includes a light source module 10 , a reflection adjustment module 20 , a projection lens 30 , a light modulation module 40 , a first collimating lens 50 , a scattering module 60 and a waveguide 70 .
[0057] Optionally, the projection display device further includes a light reflection module 80, which is disposed in the light emitting direction of the reflection adjustment module 20, and is used to reflect the collimated light beam to the scattering module 60. Furthermore, after the scattering module 60 adjusts the divergence angle of the light beam reflected by the light reflection module 80, it emits to the light modulation module 40 at a first divergence angle, so that the illumination area of the light beam emitted to the light modulation module 40 at the first divergence angle moves sequentially on the light modulation module 40 according to a plurality of target movement trajectories, and thus uniform illumination within the field of view of the entire projection display device can be achieved.
[0058] In this embodiment, the light source module 10 is located beside the projection lens 30 to facilitate the arrangement of the driving mechanism in the reflection adjustment module 20, and the setting of the light reflection module 80 can reduce the optical path of the light beam in the projection display device, thereby reducing the size of the illumination area of the light beam irradiated on the scattering module 60. By reducing the size of the illumination area of the light beam, the multiple pixel units on the light modulation module 40 can be divided into a larger number of areas to be illuminated. In this way, when the reflection adjustment module 20 controls the illumination area of the light beam to move on the light modulation module 40, the setting of more areas to be illuminated on the light modulation module 40 makes it possible for the projection display device to have a higher utilization rate of the light beam when the illumination intensity of the light beam emitted by the light source module 10 is dynamically adjusted by the control module, thereby further reducing the power consumption of the projection display device.
[0059] Please refer to Figure 6 , Figure 6 FIG. 2 shows a schematic diagram of the structure of a projection display device provided by another embodiment of the present application. Figure 6 As shown, the projection display device at least includes a light source module 10 , a reflection adjustment module 20 , a projection lens 30 , a light modulation module 40 and a waveguide 70 .
[0060] In this embodiment, the projection display device further includes a second collimating lens 90, which is disposed between the light source module 10 and the light modulation module 40. If the light source module 10 is a light source with a small expansion amount, such as a laser light source, the second collimating lens 50 is disposed in the light emitting direction of the light source module 10, and the divergence angle of the light beam emitted by the light source module 10 is adjusted by the second collimating lens 50 so that it is emitted to the surface of the reflection adjustment module 20 at a first divergence angle, and the reflection adjustment module 20 then reflects the light beam with the first divergence angle to the light modulation module 40; or, the second collimating lens 50 is disposed in the light emitting direction of the reflection adjustment module 20 (not shown), and the divergence angle of the light beam reflected by the reflection adjustment module 20 is adjusted by the second collimating lens 50 so that it is emitted to the surface of the light modulation module 40 at the first divergence angle. Wherein, the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
[0061] Optionally, the position of the second collimating lens 90 relative to the light source module 10 is movable, and the divergence angle of the light beam projected to the light modulation module 40 is positively correlated with the first distance, and the first distance is the relative distance between the focus of the second collimating lens 90 and the light source module 10. The projection display device can adjust the divergence angle of the light beam projected to the light modulation module 40 by adjusting the distance between the second collimating lens 90 and the light source module 10, thereby adjusting the size of the illumination area of the light beam emitted to the light modulation module 40. In this way, when the reflection adjustment module 20 controls the illumination area of the light beam to move on the light modulation module 40, the setting of more areas to be illuminated on the light modulation module 40 makes it possible for the projection display device to have a higher utilization rate of the light beam when the illumination intensity of the light beam emitted by the light source module 10 is dynamically adjusted by the control module, thereby further reducing the power consumption of the projection display device.
[0062] In this embodiment, the distance between the second collimating lens 90 and the light source module 10 is adjusted to adjust the divergence angle of the light beam projected onto the light modulation module 40. If the divergence angle of the light beam passing through the second collimating lens 90 is relatively large, the arrangement of optical elements with light scattering function in the projection display device can be reduced, thereby simplifying the projection display device and reducing the preparation cost of the device.
[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A projection display device, characterized in that: The projection display device comprises: A light source module, the light source module is used to emit a light beam; A reflection adjustment module is arranged in the light emitting direction of the light source module, and is used to adjust the propagation direction of the light beam emitted by the light source module, so as to control different areas on the light modulation module to be irradiated by the light beam emitted by the light source module at different times; a projection lens, disposed between the reflection adjustment module and the light modulation module, and used for adjusting the projection direction of the light beam emitted by the reflection adjustment module, so as to project the light beam with the adjusted projection direction to the light modulation module; The light modulation module is used to modulate the projected light beam and output the modulated image light to the projection lens. The image light is used to be projected by the projection lens to the area to be displayed to form a projection image.
2. The projection display device according to claim 1, characterized in that: The reflection adjustment module adjusts the adjustment frequency of the light beam propagation direction in the fast axis direction of the light beam emitted by the light source module to a first frequency, and adjusts the adjustment frequency of the light beam propagation direction in the slow axis direction of the light beam emitted by the light source module to a second frequency, so as to control the illumination area of the light beam projected onto the light modulation module to move sequentially on the light modulation module according to multiple target movement trajectories, wherein the fast axis direction is parallel to the first side of the light modulation module, the slow axis direction is parallel to the second side of the light modulation module, and the length of the first side is greater than the length of the second side.
3. The projection display device according to claim 2, characterized in that: The relative distance between adjacent target movement tracks is negatively correlated with both the first frequency and the second frequency, and the size of a single illumination area of the light beam projected onto the light modulation module on the light modulation module is positively correlated with the divergence angle of the light beam projected onto the light modulation module; During the time when the projection display device displays a frame of projection image, after the illumination area of the light beam projected onto the light modulation module moves sequentially on the light modulation module according to the multiple target movement trajectories, the area composed of the multiple illumination areas covers the light modulation module.
4. The projection display device according to claim 3, characterized in that: The first frequency matches the resonant frequency of the reflection adjustment module, the second frequency matches the refresh rate of the projected image, the reflection adjustment module is used to control the illumination area of the light beam projected onto the light modulation module to move row by row on the light modulation module, the first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 30 Hz and less than 500 Hz.
5. The projection display device according to claim 3, characterized in that: Both the first frequency and the second frequency match the resonant frequency of the reflection adjustment module, and the reflection adjustment module is used to control the simple harmonic movement of the illumination area of the light beam projected onto the light modulation module on the light modulation module. The first frequency is greater than 500 Hz and less than 20,000 Hz, and the second frequency is greater than 200 Hz and less than 5,000 Hz.
6. The projection display device according to claim 3, characterized in that: The projection display device further includes a first collimating lens, which is disposed between the light source module and the reflection adjustment module, and is used for collimating the light beam emitted from the light source module and then emitting the light beam to the reflection adjustment module.
7. The projection display device according to claim 6, characterized in that: The projection display device also includes a scattering module, which is arranged in the light emitting direction of the reflection adjustment module. The scattering module is used to adjust the divergence angle of the collimated light beam and then emit it so that it is emitted to the light modulation module at a first divergence angle, wherein the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
8. The projection display device according to claim 7, characterized in that: The projection display device also includes a light reflection module; The light reflection module is arranged in the light emitting direction of the reflection adjustment module, and the light reflection module is used to reflect the collimated light beam to the scattering module; The scattering module is used to adjust the divergence angle of the light beam reflected by the light reflecting module so that the light beam is emitted to the light modulating module at the first divergence angle.
9. The projection display device according to claim 8, characterized in that: The light source module is located beside the projection lens.
10. The projection display device according to claim 3, characterized in that: The projection display device further includes a second collimating lens, which is disposed between the light source module and the light modulation module; The second collimating lens is used to adjust the divergence angle of the target light beam and then emit it so that it is emitted to the light modulation module at a first divergence angle. The target light beam is the light beam emitted by the light source module or the light beam reflected by the reflection adjustment module, wherein the first divergence angle is greater than 0.5 degrees and less than 5 degrees.
11. The projection display device according to claim 10, characterized in that: The position of the second collimating lens relative to the light source module is movable, and the divergence angle of the light beam projected to the light modulation module is positively correlated with the first distance, which is the relative distance between the focus of the second collimating lens and the light source module.
12. The projection display device according to any one of claims 1 to 11, characterized in that: The projection display device further comprises a waveguide, wherein the waveguide is arranged in the light emitting direction of the projection lens, and the waveguide and the reflection adjustment module are arranged on the same side of the projection lens; The waveguide is used to perform total reflection transmission on the image light, so as to project the image light to the area to be displayed to form the projection image.