Dimming device and projection equipment

Abstract

The utility model relates to the technical field of projection display, and discloses a dimming device which comprises a light modulator used for modulating light source light into image light; the heat dissipation assembly is located on one side of the light modulator and used for dissipating heat of the light modulator; and the semiconductor cooler is located between the light modulator and the heat dissipation assembly and used for adjusting the temperature of the light modulator. The utility model further relates to projection equipment. The dimming device and the projection equipment disclosed by the utility model are beneficial to improving the heating power and the temperature rise response speed.

Description

Technical Field

[0001] This application relates to the field of projection display technology, and in particular to a dimming device and a projection device including the dimming device. Background Technology

[0002] The optical modulator needs to adjust its temperature during operation, but existing optical modulator temperature adjustment schemes have drawbacks such as low heating power and slow temperature rise response. Utility Model Content

[0003] This application discloses a dimming device and a projection device that can improve the heating power and temperature rise response speed of a light modulator.

[0004] The first aspect of this application relates to a dimming device, comprising: an optical modulator for modulating light from a light source into image light; a heat dissipation component located on one side of the optical modulator for dissipating heat from the optical modulator; and a semiconductor cooler located between the optical modulator and the heat dissipation component for regulating the temperature of the optical modulator.

[0005] Optionally, the semiconductor cooler has a heating mode and a cooling mode; in the heating mode, the semiconductor cooler heats up the optical modulator; in the cooling mode, the semiconductor cooler cools down the optical modulator.

[0006] Optionally, the dimming device further includes a first thermally conductive layer; the first thermally conductive layer is located between the optical modulator and the semiconductor cooler.

[0007] Optionally, the dimming device further includes a second thermally conductive layer; the second thermally conductive layer is located between the semiconductor cooler and the heat dissipation component.

[0008] Optionally, the light modulator has a first surface and a second surface disposed opposite to each other; the first surface is used to reflect and receive the image light, the heat dissipation component is located on one side of the second surface, and the semiconductor cooler is disposed between the second surface and the heat dissipation component.

[0009] The second aspect of this application relates to a projection device, including any of the dimming devices described above.

[0010] Optionally, the projection device further includes a temperature controller connected to the thermoelectric cooler; the temperature controller is used to control the thermoelectric cooler to adjust the temperature of the light modulator.

[0011] Optionally, the projection device further includes a first temperature sensor electrically connected to the temperature controller, the first temperature sensor being used to monitor the ambient temperature of the environment in which the projection device is located in real time.

[0012] Optionally, the projection device further includes a second temperature sensor electrically connected to the temperature controller, the second temperature sensor being used to monitor the real-time temperature of the light modulator.

[0013] Optionally, the projection device further includes a light source electrically connected to the temperature controller, the light source being used to generate the light source light; the temperature controller is also used to adjust the brightness of the light source.

[0014] The aforementioned dimming device and projection equipment, by incorporating a semiconductor cooler to regulate the temperature of the light modulator, can improve the heating power and temperature rise response speed of the light modulator, thereby enhancing the user experience. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the projection device according to an embodiment of this application.

[0017] Figure 2 for Figure 1 A schematic diagram of the structure of the optical modulation module.

[0018] Figure 3 for Figure 1 A schematic diagram of some modules of a projection device.

[0019] Figure 4 This is a graph showing the change in the operating temperature of the optical modulator in the test structure over time.

[0020] Explanation of main component symbols

[0021] Projection equipment: 100;

[0022] Light source: 110;

[0023] Dimming device: 120;

[0024] Optical modulator: 121;

[0025] First surface: 1211;

[0026] Second surface: 1212;

[0027] Semiconductor cooler: 122;

[0028] Heat dissipation components: 123;

[0029] First thermal conductive layer: 124;

[0030] First thermal conductive layer: 125;

[0031] Projection lens: 130;

[0032] Display controller: 140;

[0033] First temperature sensor: 150;

[0034] Second temperature sensor: 160;

[0035] Temperature controller: 170;

[0036] Optical module: 180.

[0037] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this article are for illustrative purposes only.

[0040] It should be noted that the concepts of "first" and "second" mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0041] Optical modulators are commonly used in projection equipment to obtain image light by modulating the light from a light source. Optical modulators have a specific operating temperature range. When the operating temperature range is not reached, the optical modulator needs to be heated, and when the operating temperature range is exceeded, the optical modulator needs to be cooled.

[0042] Common heating methods include attaching a heating film to the optical modulator to achieve heating, including three attachment methods: (1) attaching the heating film to the non-thermal conductive material area on the back of the optical modulator; (2) attaching the heating film to the entire back of the optical modulator, which acts as a thermal interface material when not heated; and (3) attaching the heating film to the heat sink of the optical modulator.

[0043] For the above attachment method (1), the heating film is only attached to a part of the back of the optical modulator. Usually, due to the size of the device surface area, it is difficult to increase the heating power and achieve the ideal heating effect.

[0044] Although the heating film has a larger bonding area than the heating film in the above bonding method (2), the heating power is still limited at low temperatures. When heat dissipation is required at high temperatures, the heating film acts as a heat-conducting interface material, and the heat dissipation thermal resistance will become very large, resulting in poor heat dissipation conditions for the optical modulator.

[0045] For the above method (3), although the heating film has a larger attachment area than that of method (2) (because the size of the heat sink is larger than that of the optical modulator), the entire heating process first heats up the heat sink and then transfers the heat to the optical modulator. This method has a long response time and the heat sink is much larger than the optical modulator, requiring higher heating power to provide a certain temperature rise.

[0046] In summary, traditional heating film technologies suffer from drawbacks such as low heating power and slow temperature rise response, making it difficult to achieve ideal temperature regulation. This application provides a dimming device and a projection device including the dimming device. This dimming device uses a semiconductor cooler to regulate the temperature of the light modulator, which helps to improve heating power and temperature regulation efficiency.

[0047] Please see Figure 1 The projection device 100 of the first embodiment of this application includes a light source 110, a dimming device 120, a projection lens 130, and a display controller 140. The light source 110 emits light, the dimming device 120 modulates the light to generate image light, and the projection lens 130 projects the image light onto the surface of a display medium (e.g., a wall, desktop, projection screen, etc.) to display an image. The display controller 140 is electrically connected to both the light source 110 and the dimming device 120, and controls the switching of the light source 110 and the light modulation mode of the dimming device 120.

[0048] The dimming device 120 includes a light modulator 121 electrically connected to the display controller 140. The light modulator 121 is used to modulate the light source light into image light. The projection device 100 further includes an optical module 180 located between the light source 110, the dimming device 120, and the projection lens 130, for guiding, shaping, and modulating the light source light and the image light.

[0049] In this embodiment, the light source 110 includes, but is not limited to, a light-emitting diode or a laser. In this embodiment, the light modulator 121 is used to modulate the light source to generate the image light. The light modulator 121 can be an LCOS device (Liquid Crystal On Silicon), an LCD device (Liquid Crystal Display), a DMD device (Digital Micromirror Device), etc.

[0050] As described above, the light modulator 121 has a low temperature when not in operation, but generates heat during operation. Different types of light modulators 121 have different target temperature ranges. When the light modulator 121 is within the target temperature range, it exhibits good optical characteristics, resulting in better image display by the projection device 100. If the temperature of the light modulator 121 is too high, it may cause differential deformation, leading to thermal defocusing, resulting in inability to focus properly and abnormal display conditions such as color cast. For example, in this embodiment, the light modulator 121 is an LCOS device, which includes a liquid crystal layer. The liquid crystal layer is sensitive to temperature, and generally, a better display effect can be obtained when the liquid crystal layer is within the temperature range of 45-55°C.

[0051] To ensure that the optical modulator 121 is within the target temperature range, please refer to [link / reference]. Figure 2 The dimming device 120 in this embodiment also includes a thermoelectric cooler (TEC) 122 and a heat dissipation assembly 123. The heat dissipation assembly 123 is located on one side of the light modulator 121 and is used to dissipate heat from the light modulator 121. The thermoelectric cooler 122 is located between the dimming assembly 121 and the heat dissipation assembly 123 and is used to regulate the temperature of the light modulator 121.

[0052] The operating temperature of the light modulator 121 can be adjusted by setting the semiconductor cooler 122. Since the semiconductor cooler 122 can switch between heating mode and cooling mode, when the semiconductor cooler 122 is in heating mode, it can heat the light modulator 121, which is beneficial to improve the heating power and temperature rise response speed of the light modulator 121, thereby improving the user experience.

[0053] In this embodiment, the optical modulator 121 has a first surface 1211 and a second surface 1212 disposed opposite to each other; wherein, the first surface 1211 is used to receive image light and emit modulated image light, the heat dissipation component 123 is located on one side of the second surface 1212 of the optical modulator 121, and the semiconductor cooler 122 is located between the optical modulator 121 and the heat dissipation component 123.

[0054] In this embodiment, the semiconductor cooler 122 has a heating mode and a cooling mode. When the semiconductor cooler 122 is operating in the heating mode, it heats up the light modulator 121. When the semiconductor cooler 122 is operating in the cooling mode, it cools down the light modulator 121.

[0055] The projection device 100 is typically designed to operate in environments ranging from 0-40°C. Therefore, the temperature of the light modulator 121 may be relatively low during the power-on phase (from power-on to a stable operating state). As it gradually enters a stable operating state, the temperature of the light modulator 121 gradually rises to the target temperature range. This application utilizes a semiconductor cooler 122 to heat the light modulator 121 during the power-on phase, shortening the power-on period and allowing the light modulator 121 to enter a stable operating state more quickly. This enables the projection device 100 to display a better image quickly upon power-on. During the operation of the light modulator 121, the semiconductor cooler 122 can switch to cooling mode to dissipate excess heat generated by the light modulator 121, maintaining the temperature of the light modulator 121 within the target temperature range.

[0056] In this embodiment, the heat dissipation component 123 includes, for example, a fan, heat dissipation fins, etc., which are used to simultaneously dissipate heat for the optical modulator 121 when the semiconductor cooler 122 is in cooling mode, so as to improve heat dissipation efficiency, while keeping it off when the semiconductor cooler 122 is in heating mode, which is conducive to the rapid heating of the optical modulator 121.

[0057] In this embodiment, the dimming device 120 further includes a first thermally conductive layer 124 and a second thermally conductive layer 125. The first thermally conductive layer 124 is located between the optical modulator 121 and the thermoelectric cooler 122, and is in direct contact with the surfaces of both the optical modulator 121 and the thermoelectric cooler 122. The first thermally conductive layer 124 is used to improve the thermal conductivity between the optical modulator 121 and the thermoelectric cooler 122. The second thermally conductive layer 125 is located between the thermoelectric cooler 122 and the heat dissipation assembly 123, and is in direct contact with the surfaces of both the thermoelectric cooler 122 and the heat dissipation assembly 123. The second thermally conductive layer 125 is used to improve the thermal conductivity between the heat dissipation assembly 123 and the thermoelectric cooler 122. In other embodiments of this application, the dimming device 120 may also include only one of the first thermally conductive layer 124 and the second thermally conductive layer 125.

[0058] In this embodiment, the materials of the first thermally conductive layer 124 and the second thermally conductive layer 125 are each independently selected from one or more of the following: thermal interface material (TIM), thermally conductive insulating material, and thermally conductive silicone cloth. Understandably, the materials of the first thermally conductive layer 124 and the second thermally conductive layer 125 may be the same or different.

[0059] Please see Figure 3 The projection device 100 further includes a first temperature sensor 150, a second temperature sensor 160, and a temperature controller 170. The temperature controller 170 is electrically connected to the first temperature sensor 150, the second temperature sensor 160, and the thermoelectric cooler 122. The first temperature sensor 150 is used to monitor the ambient temperature of the environment where the projection device 100 is located in real time, and the temperature controller 170 can adjust the temperature of the light modulator 121 based on the ambient temperature. The second temperature sensor 160 is used to monitor the real-time temperature of the light modulator 121, and the temperature controller 170 can adjust the temperature of the light modulator 121 based on the real-time temperature. In one specific embodiment, the temperature controller 170 is used to control the thermoelectric cooler 122 to adjust the temperature of the light modulator 121 according to the ambient temperature and the real-time temperature.

[0060] In this embodiment, the temperature controller 170 outputs a driving voltage to the thermoelectric cooler 122, and switches the operating mode (heating mode, cooling mode) of the thermoelectric cooler 122 by switching the direction of the driving voltage output to the thermoelectric cooler 122. By increasing the amplitude of the driving voltage, the temperature controller 170 can increase the heating or cooling rate of the thermoelectric cooler 122; conversely, by decreasing the amplitude of the driving voltage, the temperature controller 170 can decrease the heating or cooling rate of the thermoelectric cooler 122. Therefore, by switching the operating mode of the thermoelectric cooler 122, this application can flexibly adapt to various temperature scenarios of the optical modulator 121, thereby improving the efficiency of heating and cooling.

[0061] In this embodiment, the first temperature sensor 150 and the second temperature sensor 160 are negative temperature coefficient thermistors (NTCs), and the temperature controller 170 is a proportional-integral-derivative (PID) controller. In at least one embodiment of this application, the second temperature sensor 160 used for real-time monitoring of the real-time temperature of the optical modulator 121 may be a built-in temperature sensor of the optical modulator 121 itself.

[0062] In at least one modified embodiment of this application, the temperature controller 170 may also be electrically connected to the light source 110 to adjust the brightness of the light source 110 according to the ambient temperature and the real-time temperature. The temperature controller 170 can increase the light intensity of the light source by increasing the amplitude of the light source drive signal (voltage or current), thereby increasing the heat dissipation of the light modulator 121 and allowing the light modulator 121 to reach the target temperature range more quickly, thus improving temperature rise efficiency. The temperature controller 170 can also decrease the light intensity of the light source by decreasing the amplitude of the light source drive signal (voltage or current), thereby reducing the heat dissipation of the light modulator 121 and allowing the light modulator 121 to dissipate heat more quickly until the real-time temperature drops back to the target temperature range, thus improving heat dissipation efficiency.

[0063] In one specific embodiment, when the ambient temperature is detected to be low and the real-time temperature has not reached the target temperature range, the temperature controller 170 can increase the light intensity of the light source by increasing the amplitude of the light source driving signal (voltage or current); when the ambient temperature is detected to be high and the real-time temperature has exceeded the target temperature range, the temperature controller 170 can also decrease the light intensity of the light source by decreasing the amplitude of the light source driving signal (voltage or current).

[0064] This application can flexibly adjust the temperature of the light modulator 121 to adapt to different states by collecting the ambient temperature of the projection device and the real-time temperature of the light modulator in real time. By using a semiconductor cooler, it is beneficial to improve the heating power and temperature rise response speed of the light modulator, thereby improving the user experience.

[0065] See also Figures 1 to 3 Understandably, after the projection device 100 is turned on and starts working, the first temperature sensor 150 collects the ambient temperature Ta of the environment where the projection device 100 is located in real time and feeds back the ambient temperature Ta to the temperature controller 170 in real time. The second temperature sensor 160 continuously collects the real-time temperature Tj (also known as the junction temperature) of the light modulator 121 in real time and feeds back the real-time temperature Tj to the temperature controller 170 in real time.

[0066] The temperature controller 170 has a first set temperature, a second set temperature, and a target temperature range pre-stored, wherein the target temperature range includes the second set temperature. In this embodiment, the second set temperature can be the lower boundary value of the target temperature range. For example, when the optical modulator 121 is an LCOS device, the pre-stored target temperature range is 45℃-55℃, then the second set temperature is the lower boundary value of the target temperature range, 45℃.

[0067] The real-time temperature Tj of the optical modulator 121 shows an upward trend during the startup phase, and then remains at a stable temperature value after reaching the stable operating phase. Under various ambient temperatures Ta, the real-time temperature Tj of the optical modulator 121 exhibits a trend of first increasing and then stabilizing. However, the stable temperature value achievable by the real-time temperature Tj of the optical modulator 121 varies under different ambient temperatures Ta. Furthermore, the higher the ambient temperature Ta, the higher the stable temperature value achievable by the real-time temperature Tj of the optical modulator 121.

[0068] like Figure 4 The figure shows the real-time temperature Tj of the optical modulator 121 changing over time when the ambient temperature Ta = Ta1, where point 0 represents the moment when the optical modulator 121 is turned on. According to... Figure 4 It can be seen that when the ambient temperature Ta=Ta1, the real-time temperature Tj of the optical modulator 121 first gradually increases, and then stabilizes at Tj=Tj1. That is, when the ambient temperature Ta=Ta1, the stable temperature value of the optical modulator 121 is Tj1.

[0069] In this embodiment, during the entire operation of the optical modulator 121, it is desirable that the optical modulator 121 can quickly reach a stable temperature value after startup, and that the stable temperature value of the optical modulator 121 is maintained within the aforementioned preset target temperature range. Therefore, it is necessary to test in advance the specific stable temperature values ​​that the optical modulator 121 can achieve under different ambient temperatures.

[0070] During the testing process, with Figure 2 The structure shown, after removing the first thermally conductive layer 124 and the semiconductor cooler 122, serves as the test structure. This test structure was successively placed in environments with ambient temperatures Ta = Ta1, Ta2, Ta3…Tan, and the real-time temperature Tj of the optical modulator in this test structure was obtained as a function of time. This allowed the determination of the stable temperature values ​​Tj = Tj1, Tj2, Tj3…Tjn that the optical modulator could achieve at ambient temperatures Ta = Ta1, Ta2, Ta3…Tan. Where Ta1 < Ta2 < Ta3…<Tan, Tj1 < Tj2 < Tj3…<Tjn. In other words, through the above testing process, multiple sets of mapping relationships between Ta and Tj can be obtained. Thus, the maximum temperature value that the optical modulator can achieve under various ambient temperatures (equal to this stable temperature value) can be determined.

[0071] The temperature controller 170 can determine the stable temperature value Tj that the optical modulator 121 can reach at the ambient temperature Ta based on the received ambient temperature Ta. Let Tj = Tjx = 45℃ when Ta = Tax, where 1 < x < n. Then Tax is defined as the aforementioned first set temperature.

[0072] The temperature controller 170 determines how to control the operation of the semiconductor cooler 122 based on the relationship between the ambient temperature returned by the first temperature sensor 150 and the pre-stored second set temperature, and dynamically maintains the operating temperature of the light modulator 121 within the target temperature range.

[0073] In some embodiments, the temperature controller 170 determines whether the current ambient temperature Ta is greater than or equal to a preset first set temperature Tax. If the determination is yes, it indicates that the stable temperature value that the optical modulator 121 can reach will exceed 45°C, and the real-time temperature of the optical modulator 121 will first rise to 45°C and then continue to rise.

[0074] Therefore, when the temperature controller 170 determines that the current ambient temperature Ta is greater than or equal to the first set temperature Tax, it first drives the semiconductor cooler 122 to work in heating mode, so that the real-time temperature Tj of the optical modulator 121 quickly reaches 45°C. When it receives real-time feedback that the real-time temperature Tj is greater than 45°C (i.e., the second set temperature), it switches the direction of the driving voltage to switch the semiconductor cooler 122 from heating mode to cooling mode to cool down the optical modulator 121 so that the operating temperature of the optical modulator 121 is always kept within the target temperature range.

[0075] If the temperature controller 170 determines that the current ambient temperature Ta is less than the first set temperature Tax, it indicates that the stable temperature value that the optical modulator 121 can reach (which is also equal to the highest temperature value that can be reached) is lower than 45°C (the second set temperature). It does not need to dissipate heat but needs to be continuously heated. Then the temperature controller 170 outputs a drive voltage to make the semiconductor cooler 122 continue to work in the heating mode and maintain the operating temperature of the optical modulator 121 at the second set temperature.

[0076] In this embodiment, while the temperature controller 170 outputs a drive signal to make the semiconductor cooler 122 work in heating mode, it also increases the brightness of the light source by increasing the amplitude of the light source drive signal, thereby increasing the heat dissipation of the light modulator 121, which in turn increases the heating speed of the light modulator 121 and reaches the target temperature range more quickly.

[0077] The dimming device 120 and projection device 100 described in this application, by employing a semiconductor cooler, facilitate the improvement of the heating power and temperature rise response speed of the light modulator, and help keep the light modulator 121 stably within the target temperature range. This benefits both the long-term reliability of the light modulator 121 and the improved image quality, thereby enhancing the user experience. Thus, the dimming device 120 and projection device 100, while considering user experience, also help ensure the long-term reliability of the light modulator 121.

[0078] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0079] Furthermore, while the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in a sequential order. Multitasking and parallel processing may be advantageous in certain environments. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this application. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0080] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A dimming device, characterized in that, include: An optical modulator is used to modulate light from a light source into image light; A heat dissipation component, located on one side of the optical modulator, is used to dissipate heat from the optical modulator; as well as A semiconductor cooler, located between the optical modulator and the heat dissipation assembly, is used to regulate the temperature of the optical modulator.

2. The dimming device as described in claim 1, characterized in that, The semiconductor cooler has a heating mode and a cooling mode; In the heating mode, the semiconductor cooler heats up the optical modulator; In the cooling mode, the semiconductor cooler cools the optical modulator.

3. The dimming device as described in claim 1 or 2, characterized in that, The dimming device further includes a first thermally conductive layer; the first thermally conductive layer is located between the optical modulator and the semiconductor cooler.

4. The dimming device as described in claim 1 or 2, characterized in that, The dimming device further includes a second thermally conductive layer; the second thermally conductive layer is located between the semiconductor cooler and the heat dissipation component.

5. The dimming device as described in claim 1 or 2, characterized in that, The optical modulator has a first surface and a second surface disposed opposite to each other; The first surface is used to reflect and receive the image light, the heat dissipation component is located on one side of the second surface, and the semiconductor cooler is disposed between the second surface and the heat dissipation component.

6. A projection device, characterized in that, Includes the dimming device as described in any one of claims 1-4.

7. The projection device as described in claim 6, characterized in that, The projection device also includes a temperature controller electrically connected to the semiconductor cooler; The temperature controller is used to control the semiconductor cooler to regulate the temperature of the optical modulator.

8. The projection device as described in claim 7, characterized in that, The projection device also includes a first temperature sensor electrically connected to the temperature controller, the first temperature sensor being used to monitor the ambient temperature of the environment in which the projection device is located in real time.

9. The projection device as described in claim 7, characterized in that, The projection device also includes a second temperature sensor electrically connected to the temperature controller, the second temperature sensor being used to monitor the real-time temperature of the light modulator.

10. The projection device as described in claim 7, characterized in that, The projection device also includes a light source electrically connected to the temperature controller, the light source being used to generate the light source light; the temperature controller is also used to adjust the brightness of the light source.

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