Laser projection device and projection method thereof, and laser projection system

Abstract

The present application discloses a laser projection device and its projection method, and a laser projection system, which belong to the field of laser projection technology. The laser projection device may include: a light source, a spatial dimming device, a light valve, and a lens. The spatial dimming device can dim the illumination light beam provided by the light source based on the image information of the image to be projected, so that the light intensity of at least part of the illumination light beam after dimming by the spatial dimming device is different. In this way, the difference in brightness between different areas in the image to be projected can be enlarged, so that the dynamic contrast of the image to be projected can be improved without changing the luminous brightness of the light source and without processing the image to be projected, thereby improving the display effect of the image to be projected subsequently projected through the lens.

Description

Technical Field

[0001] The present application relates to the field of laser projection technology, and in particular to a laser projection device and a projection method thereof, and a laser projection system. Background Art

[0002] The laser projection system includes a projection screen and a laser projection device. The laser projection device can project images onto the projection screen to achieve functions such as video playback.

[0003] In related technologies, in order to improve the display effect of the image projected by the laser projection device, the laser projection device needs to process the image before projecting the image to adjust the brightness of the local area of the image, thereby expanding the grayscale difference in the image, thereby achieving the purpose of enhancing the contrast of the image and making the subsequently projected image clearer.

[0004] However, when laser projection systems currently process images to enhance contrast, they are prone to over-processing, resulting in image distortion. For example, if an image contains pixels with grayscale values between 200 and 240, current laser projection systems will likely process these pixels to a grayscale value of 256, causing image distortion. Consequently, current laser projection systems are less effective at enhancing contrast, resulting in poor display quality for the subsequently projected image. Summary of the Invention

[0005] The embodiments of the present application provide a laser projection device and a projection method thereof, as well as a laser projection system. These embodiments can solve the technical problem of poor display effects of images projected by laser projection devices in the prior art. The technical solution is as follows:

[0006] In one aspect, a laser projection device is provided, comprising:

[0007] a light source for providing an illumination beam;

[0008] a spatial light modulating device for modulating the illumination light beam provided by the light source based on image information of the image to be projected, so that the light intensity of at least part of the illumination light beam after being modulated by the spatial light modulating device is different;

[0009] a light valve, configured to modulate the illumination light beam after being dimmed by the spatial light modulating device based on image information of the image to be projected;

[0010] The lens is used to project the illumination light beam modulated by the light valve into an image.

[0011] On the other hand, a projection method of a laser projection device is provided, the method being applied to the above-mentioned laser projection device, the method comprising:

[0012] Acquiring image information of an image to be projected;

[0013] Based on the image information of the image to be projected, dimming the illumination light beam provided by the light source by the spatial dimming device so that the light intensity of at least part of the illumination light beam after dimming by the spatial dimming device is different;

[0014] Based on the image information of the image to be projected, modulating the illumination light beam after being dimmed by the spatial light modulating device through a light valve;

[0015] The illumination light beam modulated by the light valve is projected into an image through a lens.

[0016] On the other hand, a laser projection system is provided, comprising: a projection screen, and the laser projection device described above.

[0017] The beneficial effects of the technical solution provided by the embodiments of the present application are:

[0018] The laser projection device may include: a light source, a spatial dimming device, a light valve, and a lens. The spatial dimming device can dim the illumination beam provided by the light source based on image information of the image to be projected, so that the intensity of at least a portion of the illumination beam after dimming by the spatial dimming device varies. This can increase the brightness difference between different areas of the projected image, thereby improving the dynamic contrast of the projected image without changing the light source's brightness or processing the projected image, thereby improving the display quality of the projected image subsequently projected through the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 This is a schematic structural diagram of a laser projection device provided in an embodiment of the present application;

[0021] Figure 2 1 is a schematic structural diagram of a spatial light modulation device provided in an embodiment of the present application;

[0022] Figure 3 is a schematic diagram of an image to be projected according to an embodiment of the present application;

[0023] Figure 4 is a grayscale histogram provided in an embodiment of the present application;

[0024] Figure 5 yes Figure 3 Schematic diagram showing 10 dimming conditions in the image to be projected;

[0025] Figure 6 This is a structural diagram of a dimming unit provided in an embodiment of the present application;

[0026] Figure 7 yes Figure 6 A side view of the position adjustment assembly is shown;

[0027] Figure 8 is a top view of a first substrate provided in an embodiment of the present application;

[0028] Figure 9 This is a flowchart of a projection method of a laser projection device provided in an embodiment of the present application;

[0029] Figure 10 This is a flowchart of another projection method of a laser projection device provided in an embodiment of the present application;

[0030] Figure 11 Schematic diagram of the structure of a laser projection system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0032] Please refer to Figure 1 , Figure 1 FIG1 is a schematic diagram of the structure of a laser projection device provided in an embodiment of the present application. The laser projection device 00 may include: a light source 100, a spatial light modulation device 200, a light valve 300 and a lens 400.

[0033] The light source 100 is used to provide an illumination beam. In the embodiment of the present application, the illumination beam provided by the light source 100 needs to be directed toward the space lighting device 200.

[0034] The spatial light modulating device 200 is configured to modulate the illumination beam provided by the light source based on image information of the image to be projected, so that the intensity of at least a portion of the illumination beam after being modulated by the spatial light modulating device 200 varies. In the embodiment of the present application, the illumination beam after being modulated by the spatial light modulating device 200 is directed toward the light valve 300.

[0035] The light valve 300 is used to modulate the illumination light beam after being dimmed by the spatial light modulating device 200 based on the image information of the image to be projected. In the embodiment of the present application, the illumination light beam modulated by the light valve 300 needs to be directed toward the lens 400.

[0036] The lens 400 is used to project the illumination light beam modulated by the light valve 300 into an image. It should be noted that the image projected by the lens 400 is the image to be projected.

[0037] In the embodiment of the present application, since at least a portion of the illumination light beam modulated by the spatial light modulating device 200 has different intensities, when the illumination light beam is converted into a projected image through the light valve 300 and the lens 400, the brightness difference between different areas of the projected image can be magnified, thereby improving the dynamic contrast of the projected image. Dynamic contrast refers to the brightness ratio between the brightest and darkest areas of the projected image.

[0038] In summary, the laser projection device provided in the embodiments of the present application includes: a light source, a spatial dimming device, a light valve, and a lens. The spatial dimming device can dim the illumination beam provided by the light source based on the image information of the image to be projected, so that the light intensity of at least part of the illumination beam after dimming by the spatial dimming device is different. In this way, the difference in brightness between different areas of the image to be projected can be increased, thereby improving the dynamic contrast of the image to be projected without changing the luminous brightness of the light source or processing the image to be projected, thereby improving the display effect of the image to be projected subsequently projected through the lens.

[0039] Optional, please refer to Figure 2 , Figure 2 : is a schematic diagram of the structure of a spatial dimming device provided in an embodiment of the present application. The spatial dimming device 200 may have multiple dimming zones 200a, and the spatial dimming device 200 may include: multiple dimming units 200b located in each dimming zone 200a. For example, the lighting beam has multiple dimming zones, and the multiple dimming zones can be arranged in an array into multiple rows and columns. For example, Figure 2 As shown, the plurality of light beam partitions can be arranged in an array of two rows and two columns. In this case, the spatial dimming device 200 has four light beam partitions. The plurality of dimming units 200b in the spatial dimming device 200 can be arranged in an array of multiple rows and multiple columns. For example, the plurality of dimming units 200b can be arranged in an array of n rows and n columns. In this case, the spatial dimming device 200 includes n 2It should be noted that the areas of the dimming zones 200a in the spatial dimming device 200 may be the same, and thus the number of dimming units 200b in the dimming zones 200a in the spatial dimming device 200 may be the same.

[0040] In the present application, the illumination beam after dimming by the spatial dimming device 200 can have multiple beam segments corresponding one-to-one with the multiple dimming segments in the spatial dimming device 200. The image to be projected can have multiple image segments corresponding one-to-one with the multiple dimming segments in the spatial dimming device 200. Thus, the multiple beam segments also correspond one-to-one with the multiple image segments. In this case, light within each beam segment in the illumination beam after dimming by the spatial dimming device 200, after passing through the light valve 300 and lens 400, can be converted into the corresponding image segment in the image to be projected.

[0041] For example, the spatial dimming device 200 is configured to dim the illumination beam provided by the light source 100 based on image information of the image to be projected, using multiple dimming units 200b located within each dimming zone 200a, so that at least two of the dimmed illumination beam zones have different intensities. This can increase the brightness difference between the two image zones created by the two beam zones with different intensities after passing through the light valve 300 and lens 400, thereby effectively improving the dynamic contrast of the projected image.

[0042] For example, the at least two beam segments include a first beam segment and a second beam segment. Assuming that the brightness of a first image segment corresponding to the first beam segment in the projected image is greater than the brightness of a second image segment corresponding to the second beam segment, the spatial light modulating device 200 can dim the illumination beam to increase the light intensity of the first beam segment to be greater than the light intensity of the second beam segment. In this manner, the light within the first beam segment, after passing through the light valve 300 and lens 400, is converted to a brighter brightness of the first image segment, while the light within the second beam segment, after passing through the light valve 300 and lens 400, is converted to a darker brightness of the second image segment. In this case, the dynamic contrast of the projected image can be improved without changing the brightness of the light source 100 or processing the projected image, thereby enhancing the display quality of the projected image subsequently projected through the lens 400.

[0043] In the embodiments of this application, Figure 2As shown, each dimming unit 200b in the spatial dimming device 200 may include a position adjustment component 201 and a reflector 202 connected to the position adjustment component 201. Each position adjustment component 201 in the spatial dimming device 200 is configured to drive the corresponding reflector 202 to move in a direction perpendicular to the reflective surface of the reflector 202. When different reflectors 202 are moved to different positions perpendicular to the reflective surface of the reflector 202 under the control of their corresponding position adjustment components 201, if an illumination light beam is directed toward reflectors 202 at different positions perpendicular to the reflective surface, the phases of the light beams reflected by the reflectors 202 at different positions will be different.

[0044] In this case, the spatial dimming device 200 can adjust the position of each reflector 202 on a reflective surface perpendicular to the reflector 202 via the multiple position adjustment components 201 within each dimming subarea 200a based on the image information of the image to be projected, so that the phases of at least a portion of the light in the illumination beam after being reflected 202 by each reflector in the spatial dimming device 200 differ. In this way, coherent interference or destructive interference may occur between the illumination beams after being reflected 202 by the respective reflectors, thereby enabling different light intensities within at least two beam subareas of the illumination beam after being dimmed by the spatial dimming device 200.

[0045] For example, the image information of the image to be projected may include: brightness information of each image partition in the image to be projected. The spatial dimming device 200 is used to: based on the brightness information of each image partition in the image to be projected, adjust the position of each reflector 202 in the first dimming partition through each position adjustment component 201 in the first dimming partition, so that at least part of the light in the first light beam partition after being reflected by the reflector 202 in the first dimming partition undergoes coherent interference; and adjust the position of each reflector 202 in the second dimming partition through each position adjustment component 201 in the second dimming partition, so that at least part of the light in the second light beam partition after being reflected by the reflector 202 in the second dimming partition undergoes destructive interference.

[0046] In the image to be projected, the brightness of the first image subarea corresponding to the first dimming subarea is greater than the brightness of the image subarea corresponding to the second dimming subarea.

[0047] In this application, because the brightness of the first image subarea in the projected image is greater than that of the second image subarea, the spatial dimming device 200 can adjust the positions of the reflectors 202 within the first dimming subarea so that the portion of light within the first beam subarea reflected by the reflectors 202 within the first dimming subarea causes coherent interference, thereby increasing the light intensity of the first beam subarea. Furthermore, the spatial dimming device 200 can adjust the positions of the reflectors 202 within the second dimming subarea so that the portion of light within the second beam subarea reflected by the reflectors 202 within the second dimming subarea causes destructive interference, thereby reducing the light intensity of the second beam subarea. In this way, after the light within the first beam subarea passes through the light valve 300 and lens 400, the brightness of the first image subarea obtained by the light within the second beam subarea is brighter, while the brightness of the second image subarea obtained by the light within the second beam subarea passes through the light valve 300 and lens 400, the brightness of the second image subarea obtained by the light within the second beam subarea is darker, thereby effectively improving the dynamic contrast of the projected image.

[0048] In the embodiment of the present application, the spatial light modulating device 200 is essentially a phase modulator. The spatial light modulating device 200 adjusts the phase of light reflected by each of the reflectors 202 of the light modulating device 200, so that light within the illumination beam modulated by the spatial light modulating device 200 may experience coherent interference or destructive interference, thereby resulting in different light intensities in two beam sections within the illumination beam.

[0049] As can be seen from the above embodiments, the spatial dimming device 200 needs to obtain brightness information for each image subarea in the projected image before dimming the illumination beam provided by the light source 100. To enable the spatial dimming device 200 to quickly obtain the brightness information for each image subarea, the embodiments of the present application can determine the brightness information for each image subarea using the following method.

[0050] Please refer to Figure 3 , Figure 3 This is a schematic diagram of an image to be projected according to an embodiment of the present application. Assume that the image to be projected has four image partitions, namely image partition L1, image partition L2, image partition L3, and image partition L4. Assume that the resolution of the image that can be transmitted by the laser projection device is 1920×1080. Then, the position of each pixel point in the image partition L1 can be expressed as: (0, 0)-(959, 539); the position of each pixel point in the image partition L2 can be expressed as: (959, 0)-(1919, 539); the position of each pixel point in the image partition L3 can be expressed as: (0, 1079)-(959, 1079); the position of each pixel point in the image partition L4 can be expressed as: (960, 540)-(1919, 1079).

[0051] For each image partition, first, the number of pixels within each grayscale interval can be counted based on the grayscale values of each pixel within the image partition. Then, the brightness information of the image partition can be determined based on each grayscale interval and the number of pixels within each grayscale interval.

[0052] For examples, please refer to Figure 4 , Figure 4 This is a grayscale histogram provided in an embodiment of the present application. The horizontal axis represents each grayscale interval, and the vertical axis represents the number of pixels within each grayscale interval. When determining the brightness information of an image partition, the median value of each grayscale interval can be multiplied by the number of pixels whose grayscale values fall within that grayscale interval, and then the resulting values can be added together. This summed data can be used to represent the brightness information of the image partition.

[0053] It should be noted that since each pixel point includes: a red sub-pixel point, a green sub-pixel point and a blue sub-pixel point, in order to facilitate the determination of the grayscale value of each pixel point, the grayscale value with the largest value among the grayscale value of the red sub-pixel point, the grayscale value of the green sub-pixel point and the grayscale value of the blue sub-pixel point in each pixel point can be determined as the grayscale value of the pixel point.

[0054] After the spatial dimming device 200 obtains the brightness information of each image partition in the image to be projected through the above-mentioned implementation method, the spatial dimming device 200 can control the position of each reflector 202 through the position adjustment component 201, so that the light intensity in at least two beam partitions of the illumination light beam after dimming by the spatial dimming device 200 is different, thereby expanding the difference in brightness between the image partitions of at least two image partitions corresponding to the at least two beam partitions.

[0055] In the embodiment of this application, for Figure 3 There are 10 situations where dimming is required for each image partition of the projected image. Figure 5 , Figure 5 yes Figure 3 FIG. 1 is a schematic diagram showing 10 dimming conditions in an image to be projected. Figure 5 The 10 schematic diagrams in FIG. 1 represent the position distribution diagrams of the image partitions that need to be brightened and dimmed in the projected image. Figure 5In the projected image, white areas represent areas with higher brightness, while black areas represent areas with lower brightness. In this application, the spatial dimming device can increase the intensity of the light beam areas corresponding to the areas with higher brightness, making them brighter, and reduce the intensity of the light beam areas corresponding to the areas with lower brightness, making them darker.

[0056] Since the spatial light modulating device 200 can adjust the phase of the light in the illumination beam by adjusting the position of each reflector 202 on the reflective surface perpendicular to the reflector 202, and the spatial light modulating device 200 only adjusts the light intensity in each beam partition of the illumination beam. Figure 5 The 10 dimming conditions for the projected image are shown. Before the laser projector leaves the factory, the positions of the reflectors 201 in the spatial dimming device 200 for each dimming condition can be determined. This allows the laser projector to directly determine the dimming condition for the projected image based on the brightness information of each image subarea within the projected image. By controlling the reflectors 201 in the spatial dimming device 200 to move to the corresponding positions, the contrast of the projected image can be improved.

[0057] The following examples are Figure 5 The schematic diagram in the first row and first column shows the position distribution of the image subareas that need to be brightened and dimmed in the projected image as an example, and the position of each reflector 201 in the spatial light modulating device 200 is schematically explained as an example:

[0058] exist Figure 5 In the first row and first column of the diagram, if spatial dimming device 200 is not used, the light intensities of the four light beam sub-areas corresponding to the four image sub-areas are identical before entering light valve 300, and the light energy distribution of the four light beam sub-areas is also identical. For example, assuming the total light energy of the illumination light beam provided by light valve 100 is A, the light energy of each of the four light beam sub-areas is A / 4.

[0059] exist Figure 5 In the schematic diagram located in the first row and first column, if the spatial dimming device 200 is required, then before entering the light valve 300, the light intensities of at least two of the four light beam partitions corresponding to the four image partitions are different, and the distribution of the light energy of the at least two light beam partitions is also different.

[0060] for Figure 5The dimming situation shown in the first row and first column of the diagram can manually set the light energy in each image partition. For example, assuming that the total light energy of the illumination beam provided by the light valve 100 is A, the light energy can be set manually. Figure 5 The light energy of each of the three image subareas with higher brightness in the first row and first column of the schematic diagram is greater than A / 4, and it is stipulated that Figure 5 In the diagram of the first row and first column, the light energy of a low-brightness image partition is less than A / 4. Figure 5 The total light energy of the four beam partitions in the first row and first column of the schematic diagram is A.

[0061] In this way, the amplitude and phase of the light at each position in the illumination beam after being dimmed by the spatial dimming device 200 can be obtained through optical simulation. In this case, the light wave function of the illumination beam after being dimmed by the spatial dimming device 200 is g = B(x, y) exp[iφ1(x, y)].

[0062] Here, B(x, y) represents the amplitude distribution of the illumination beam after being dimmed by the spatial dimming device 200; φ1(x, y) represents the phase distribution of the illumination beam after being dimmed by the spatial dimming device 200; and (x, y) represents the position of each dimming unit 200b in the spatial dimming device 200. Since B(x, y) and φ1(x, y) are both known quantities, the light wave function g is also a known quantity.

[0063] Once the structure of the light source 100 is determined, the amplitude and phase of the light at each position in the illumination beam provided by the light source 100 can be determined. In this case, the light wave function of the illumination beam provided by the light source 100 is f = A(x, y) exp[iφ2(x, y)].

[0064] Here, A(x, y) represents the amplitude distribution of the illumination beam provided by light source 100, and φ2(x, y) represents the phase distribution of the illumination beam after being dimmed by spatial light modulating device 200. Since both A(x, y) and φ2(x, y) are known quantities, the light wave function f is also known.

[0065] Because the spatial dimming device 200 is a phase modulator, it can adjust the phase of the illumination beam provided by the light source. Therefore, the phase distribution required for adjustment by the spatial dimming device 200 can be derived from the optical wave functions g and f. Thus, the position of each reflector 202 in the spatial dimming device 200 on a reflective surface perpendicular to the reflector 202 can be determined based on the phase distribution required for adjustment.

[0066] For example, based on the optical wave function g and the optical wave function f, the phase distribution that needs to be adjusted by the spatial light modulating device 200 can be determined by using a Gerchberg-Saxton (abbreviated as GS) phase recovery algorithm.

[0067] The light wave function g and the light wave function f satisfy the following conditions:

[0068] f=F(g), g=F -1 (f);

[0069] Where F represents Fourier transform, that is, after Fourier transforming the light wave function f, the light wave function g can be obtained; F -1 The inverse Fourier transform is indicated, that is, after performing the inverse Fourier transform on the light wave function g, the light wave function f can be obtained.

[0070] Thus, the process of the GS phase recovery algorithm is as follows: multiple phase iteration processes are performed on the light wave function f until the iteration condition is met, and the phase distribution outputted last is determined as the phase distribution required to be adjusted by the spatial dimming device 200. Each iteration process may include:

[0071] Step S1: Perform Fourier transform on the light wave function f=Aexp(iφ) to obtain the light wave function g'=B' exp(iφ).

[0072] Step S2: After replacing the amplitude B' in the optical wave function g'=B'exp(iφ') with the amplitude B, perform an inverse Fourier transform on it to obtain the optical wave function f'=A'exp(iφ').

[0073] Step S3: After replacing the amplitude A' in the light wave function f'=A'exp(iφ') with A, perform the Fourier transform process in step S1 on it and output the corresponding phase distribution.

[0074] In an embodiment of the present application, after repeatedly executing the phase iteration process of steps S1 to S3 above for multiple times, if the iteration condition is met, the phase distribution output last time can be determined as the phase distribution that needs to be adjusted by the spatial dimming device 200.

[0075] The iteration condition may be that the difference between the phase φ' in the optical wave function g' and the phase φ in the optical wave function g is less than a preset threshold, and the difference between the phase φ' in the optical wave function f' and the phase φ in the optical wave function f is less than a preset threshold.

[0076] It should be noted that the above embodiment provides an exemplary description of the dimming principle of the spatial light modulating device 200. The following embodiment will describe the principle of the adjustment component 201 in the spatial light modulating device 200 adjusting the position of the reflector 201 in a direction perpendicular to its reflective surface:

[0077] like Figure 6 As shown, Figure 6 2 is a schematic structural diagram of a dimming unit provided in an embodiment of the present application. The position adjustment assembly 201 in the dimming unit 200b may include: a first substrate 2011 and a second substrate 2012 disposed opposite each other, and a drive structure 2013 located between the first substrate 2011 and the second substrate 2012. The reflector 202 may be located on a side of the second substrate 2012 away from the first substrate 2011. The reflector 202 may be stacked on the second substrate 2012, with the reflective surface of the reflector 202 located on a side away from the second substrate 2012. The drive structure 2013 is configured to drive the second substrate 2012 to move in a direction perpendicular to the second substrate 2012, thereby driving the reflector 202 to move in a direction perpendicular to the reflector 202.

[0078] In the embodiments of this application, Figure 7 As shown, Figure 7 yes Figure 6 The driving structure 2013 may include: at least one driving electrode 2013a located on a side of the first substrate 2011 close to the second substrate 2012; a common electrode 2013b located on a side of the second substrate 2012 close to the first substrate 2011; and a plurality of elastic support members 2013c located between the first substrate 2011 and the second substrate 2012.

[0079] It should be noted that the first substrates 2011 in the plurality of dimming units 200 b in the spatial dimming device 200 are reused, that is, the plurality of first substrates 2011 in the plurality of dimming units 200 b are a whole substrate.

[0080] One end of each elastic support member 2013c may be fixedly connected to the driving electrode 2013a, and the other end may be fixedly connected to the common electrode 2013b.

[0081] It should be noted that when the first substrate 2011 includes a plurality of driving electrodes 2013 a close to at least one driving electrode 2013 a on the second substrate 2012 , a gap exists between any two driving electrodes 2013 a among the plurality of driving electrodes 2013 a .

[0082] In the present application, the common electrode 2013b provided on the side of the second substrate 2012 close to the first substrate 2011 may be a plate-shaped electrode, and the common electrode 2013b may always be loaded with a voltage of 0V, that is, the common electrode 2013b is grounded.

[0083] At least one driving electrode 2013a arranged on the side of the first substrate 2011 close to the second substrate 2012 is used to: adjust the distance between the first substrate 2011 and the second substrate 2012 by loading the same voltage as the common electrode 2013b, or a voltage different from the common electrode 2013b to each driving electrode 2013a, so as to adjust the position of the reflector 202 on the side of the second substrate 2012 away from the first substrate 2011.

[0084] For example, the driving structure 2013 in the embodiment of the present application may further include: a driving circuit ( Figure 6 and Figure 7 (not shown). The driving circuit is used to apply the same voltage as the common electrode 2013b, or a different voltage from the common electrode 2013b, to the driving electrode 2013a. For example, the driving circuit includes a power supply terminal and a driving transistor located between the power supply terminal and the driving electrode 2013a. When the driving transistor is turned on, the power supply terminal can apply a voltage to the driving electrode 2013a. In this case, the driving electrode 2013a is loaded with a voltage different from the common electrode 2013b. When the driving transistor is turned off, the power supply terminal cannot apply a voltage to the driving electrode 2013a. In this case, the driving electrode 2013a is loaded with the same voltage as the common electrode 2013b, that is, 0 volts.

[0085] In the embodiment of the present application, when a voltage different from that of the common electrode 2013b is loaded on the driving electrode 2013a, a voltage difference is formed between the driving electrode 2013a and the common electrode 2013b, so that an electric adsorption force is generated between the first substrate 2011 and the second substrate 2012. Under the action of this electric adsorption force, the second substrate 2012 can be driven to move in a direction perpendicular to the second substrate 2012 to adjust the distance between the first substrate 2011 and the second substrate 2012.

[0086] It should be noted that, when the second substrate 2012 moves in a direction perpendicular to the second substrate 2012 , the plurality of elastic supporting members 2013 c located between the first substrate 2011 and the second substrate 2012 need to be stretched or contracted.

[0087] It should also be noted that the magnitude of the electrical attraction force generated between the first substrate 2011 and the second substrate 2012 is related to the area of the drive electrode 2013a (which needs to be loaded with a different voltage than the common electrode 2013b). Therefore, by providing multiple drive electrodes 2013a on the side of the first substrate 2011 closer to the second substrate 2012, the positional relationships between the first substrate 2011 and the second substrate 2012 can be controlled to form a variety of positions, allowing the reflector 202 on the side of the second substrate 2012 farther from the first substrate 2011 to be positioned in a variety of different positions, thereby effectively improving the dimming accuracy of the spatial light modulating device 200 in dimming the illumination beam.

[0088] For example, Figure 8 As shown, Figure 8 2 is a top view of a first substrate provided in an embodiment of the present application. The at least one drive electrode 2013a on the side of the first substrate 2011 near the second substrate 2012 may include: a plurality of nested annular drive electrodes, and a plate-shaped drive electrode located in the central region of the plurality of annular drive electrodes. In this way, the areas of the drive electrodes on the side of the first substrate 2011 near the second substrate 2012 are different. After applying a voltage (i.e., a voltage different from that of the common electrode 2013b) to different drive electrodes 2013a on the side of the first substrate 2011 near the second substrate 2012, a variety of electric adsorption forces of varying magnitudes can be generated between the first substrate 2011 and the second substrate 2012, thereby varying the distance between the first substrate 2011 and the second substrate 2012. In other words, a variety of positional relationships between the first substrate 2011 and the second substrate 2012 can be controlled.

[0089] For example, the at least one drive electrode 2013a on a side of the first substrate 2011 near the second substrate 2012 may include: a drive electrode A, a drive electrode B, and a drive electrode C. The drive electrodes A and B may be ring-shaped drive electrodes, and the drive electrode C may be a plate-shaped drive electrode located in the center of the ring-shaped drive electrodes. Applying a voltage to each of the drive electrodes A, B, and C (either the same voltage as the common electrode 2013b or a different voltage from the common electrode 2013b) may cause the distance between the first substrate 2011 and the second substrate 2012 to vary. For example, please refer to Table 1, which shows a corresponding relationship between the distances between the first substrate 2011 and the second substrate 2012 after applying a voltage to each of the drive electrodes A, B, and C.

[0090] Table 1

[0091] Driving electrode A Driving electrode B Driving electrode C The distance between the first substrate and the second substrate 0 0 0 L1 V 0 0 L2 0 V 0 L3 0 0 V L4 V V 0 L5 V 0 V L6 0 V V L7 V V V L8

[0092] As shown in Table 1, when a voltage of 0 volts is applied to the driving electrode, the same voltage as the common electrode 2013b is applied to the driving electrode; when a voltage of V volts is applied to the driving electrode, a different voltage from the common electrode 2013b is applied to the driving electrode. For example, when a voltage of 0 volts is applied to driving electrode A, driving electrode B, and driving electrode C, the distance between the first substrate 2011 and the second substrate 2012 is L1; when a voltage of V volts is applied to driving electrode A, and a voltage of 0 volts is applied to driving electrode B and driving electrode C, the distance between the first substrate 2011 and the second substrate 2012 is L2.

[0093] According to Table 1, when three driving electrodes are set on the side of the first substrate 2011 close to the second substrate 2012, 8 positional relationships can be generated between the first substrate 2011 and the second substrate 2012. In this way, the reflector 202 on the side of the second substrate 2012 away from the first substrate 2011 can be located at 8 different positions.

[0094] In the embodiments of this application, Figure 3 and Figure 4 As shown, the at least one ring-shaped driving electrode 2013a disposed on the side of the first substrate 2011 near the second substrate 2012 can be a rectangular ring-shaped driving electrode; the plate-shaped driving electrode in the at least one driving electrode 2013a can be a rectangular plate-shaped driving electrode. For a rectangular ring-shaped driving electrode, four elastic support members 2013 are required to connect to the rectangular ring-shaped driving electrode, and the four elastic support members 2013 are respectively located at the four corners of the rectangular ring-shaped driving electrode. For a rectangular plate-shaped driving electrode, one elastic support member 2013 is required to connect to the rectangular plate-shaped driving electrode, and the elastic support member 2013 can be located in the central region of the rectangular plate-shaped driving electrode.

[0095] It should be noted that, in the above embodiment, the position adjustment component 201 in the spatial light modulation device 200 controls the reflector 202 to move in a direction perpendicular to the reflective surface of the reflector 202 to adjust the phase of the light in the illumination beam.

[0096] In other optional implementations, the position adjustment component 201 in the spatial light modulating device 200 can further control the reflector 202 to rotate along its diagonal direction to adjust the phase of the light in the illumination beam. In this case, the spatial light modulating device 200 can be a digital micromirror device (DMD) light valve. This embodiment of the present application is not specifically limited to this.

[0097] In the embodiment of the present application, the light source 100 may include a laser, a phosphor wheel, a color filter wheel, and a reflective component. The laser may be a blue laser. The blue laser emits blue light, which then passes through the phosphor wheel to generate red and green light. The blue, red, and green light then pass through the color filter wheel and are then reflected by the reflective component to the spatial light modulating device 200.

[0098] The light valve 300 may include: a light adjustment component, a prism component, and a DMD light valve. The light adjustment component can receive the illumination beam after dimming by the spatial dimming device 200 and transmit the illumination beam to the prism component; the prism component can receive the illumination beam emitted from the light adjustment component and transmit the illumination beam emitted from the light adjustment component to the light-receiving surface of the DMD light valve after two reflections; the DMD light valve can modulate the illumination beam emitted from the prism component based on the image signal and reflect the modulated illumination beam to the lens. Optionally, the resolution of the reflector in the spatial dimming device 200 is less than or equal to the resolution of the reflector in the DMD light valve in the light valve 300. In other words, the number of reflectors in the spatial dimming device 200 is less than or equal to the number of reflectors in the DMD light valve in the light valve 300.

[0099] The lens 400 may include: a plurality of lens groups, each of which may be composed of lenses such as a convex lens and a concave lens. The plurality of lens groups can project the illumination light beam reflected by the DMD light valve in the light valve 300 into an image.

[0100] In summary, the laser projection device provided in the embodiments of the present application includes: a light source, a spatial dimming device, a light valve, and a lens. The spatial dimming device can dim the illumination beam provided by the light source based on the image information of the image to be projected, so that the light intensity of at least part of the illumination beam after dimming by the spatial dimming device is different. In this way, the difference in brightness between different areas of the image to be projected can be increased, thereby improving the dynamic contrast of the image to be projected without changing the luminous brightness of the light source or processing the image to be projected, thereby improving the display effect of the image to be projected subsequently projected through the lens.

[0101] The embodiment of the present application also provides a projection method of a laser projection device, such as Figure 9 As shown, Figure 9 This is a flowchart of a projection method of a laser projection device provided in an embodiment of the present application. The projection method is applied to Figure 1 The laser projection device 00 is shown. The projection method may include:

[0102] Step 901: Acquire image information of an image to be projected.

[0103] Step 902: Based on the image information of the image to be projected, dim the illumination beam provided by the light source through the spatial dimming device, so that the light intensity of at least part of the illumination beam after dimming by the spatial dimming device is different.

[0104] Step 903: Based on the image information of the image to be projected, the illumination light beam dimmed by the spatial light modulating device is modulated by the light valve.

[0105] Step 904: Project the illumination light beam modulated by the light valve into an image through a lens.

[0106] In summary, the projection method for a laser projection device provided in the embodiments of the present application uses a spatial dimming device to dim the illumination beam provided by a light source, so that the intensity of at least a portion of the illumination beam after dimming by the spatial dimming device varies. This can increase the brightness differences between different areas of the projected image, thereby improving the dynamic contrast of the projected image without changing the luminous brightness of the light source or otherwise processing the projected image. This, in turn, improves the display quality of the projected image subsequently projected through the lens.

[0107] Please refer to Figure 10 , Figure 10 This is a flowchart of another projection method of a laser projection device provided in an embodiment of the present application. The projection method is applied to Figure 1 The laser projection device 00 is shown. The projection method may include:

[0108] Step 1001: Obtain image information of an image to be projected.

[0109] In an embodiment of the present application, the controller in the laser projection device can obtain image information of the image to be projected.

[0110] Step 1002: Based on the image information to be projected, determine the brightness information of each image subarea in the image to be projected.

[0111] In an embodiment of the present application, the controller in the laser projection device can determine the brightness information of each image partition in the image to be projected based on the image information to be projected.

[0112] In the present application, the image to be projected has at least two image partitions, and the at least two image partitions may correspond one-to-one to at least two dimming partitions in the spatial dimming device.

[0113] It should be noted that the method for determining the brightness information of each image partition in the image to be projected can refer to the corresponding content in the above embodiment, and the embodiment of the present application will not be repeated here.

[0114] Step 1003: Based on the brightness information of each image partition in the image to be projected, the position of each reflector in the spatial light modulating device in a direction perpendicular to the reflective surface of the reflector is adjusted so that the phase of at least part of the light in the illumination light beam reflected by each reflector in the spatial light modulating device is different.

[0115] In an embodiment of the present application, a controller in the laser projection device can adjust the position of each reflector in a spatial light modulating device in a direction perpendicular to the reflective surface of the reflector based on brightness information of each image sub-area in the projected image, so that the phases of at least a portion of the illumination light reflected by each reflector in the spatial light modulating device differ. In this way, in the illumination light beam reflected by each reflector in the spatial light modulating device, light in one beam sub-area may coherently interfere, while light in another beam sub-area may destructively interfere, resulting in different light intensities in the two beam sub-areas.

[0116] For example, the illumination light beam after dimming by the spatial light dimming device has at least two light beam partitions corresponding one-to-one to the at least two dimming partitions.

[0117] Assume that, in the image to be projected, the brightness of the first image subarea corresponding to the first dimming subarea is greater than the brightness of the second image subarea corresponding to the second dimming subarea. Then, through the position adjustment components within the first dimming subarea of the spatial dimming device, the positions of the respective reflectors within the first dimming subarea can be adjusted so that at least a portion of the light within the first light beam subarea, after being reflected by the reflectors within the first dimming subarea, undergoes coherent interference; and through the position adjustment components within the second dimming subarea of the spatial dimming device, the positions of the respective reflectors within the second dimming subarea can be adjusted so that at least a portion of the light within the second light beam subarea, after being reflected by the reflectors within the second dimming subarea, undergoes destructive interference. In this way, the light intensity of the first light beam subarea is greater than the light intensity of the second light beam subarea. After the light within the first light beam subarea subsequently passes through the light valve and lens, the brightness of the first image subarea obtained by conversion is brighter, while the light within the second light beam subarea subsequently passes through the light valve and lens, the brightness of the second image subarea obtained by conversion is darker, thereby effectively improving the dynamic contrast of the image to be projected.

[0118] Step 1004 : Based on the image information of the image to be projected, the illumination light beam dimmed by the spatial light modulating device is modulated by a light valve.

[0119] In an embodiment of the present application, the controller in the laser projection device can modulate the illumination light beam after being dimmed by the spatial dimming device through a light valve based on image information of the image to be projected.

[0120] Step 1005: Project the illumination light beam modulated by the light valve into an image through a lens.

[0121] In an embodiment of the present application, the controller in the laser projection device can project the illumination light beam modulated by the light valve into an image through a lens.

[0122] It should be noted that the working principles and structures of the various components in the laser projection device described above can refer to the aforementioned embodiments describing the structure of the laser projection device, and the embodiments of the present application will not be repeated here.

[0123] In summary, the projection method for a laser projection device provided in the embodiments of the present application uses a spatial dimming device to dim the illumination beam provided by a light source, so that the intensity of at least a portion of the illumination beam after dimming by the spatial dimming device varies. This can increase the brightness differences between different areas of the projected image, thereby improving the dynamic contrast of the projected image without changing the luminous brightness of the light source or otherwise processing the projected image. This, in turn, improves the display quality of the projected image subsequently projected through the lens.

[0124] The embodiment of the present application also provides a laser projection system, such as Figure 11 As shown, Figure 11 This is a schematic diagram of the structure of a laser projection system provided by an embodiment of the present application. The laser projection system may include: a laser projection device 00 and a projection screen 01. The laser projection device 00 may be Figure 1 The image projected by the lens 400 in the laser projection device 00 can be located within the projection screen 01 .

[0125] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless expressly limited otherwise.

[0126] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A laser projection device, characterized in that: include: a light source for providing an illumination beam; A spatial dimming device having at least two dimming zones and a plurality of dimming units located in each of the dimming zones, each of the dimming units comprising: a position adjustment component and a reflector connected to the position adjustment component; The spatial dimming device is configured to: determine a dimming condition of the image to be projected from a plurality of dimming conditions based on brightness information of at least two image subareas in the image to be projected that correspond one-to-one to the at least two dimming subareas; and according to the dimming condition of the image to be projected, for any dimming subarea, adjust the position of each reflector in a direction perpendicular to the reflective surface of the reflector by means of each position adjustment component in the any dimming subarea, and control the reflector to rotate along the direction of its diagonal, so that the phases of at least part of the light in the illumination light beam reflected by each reflector in the any dimming subarea are different, thereby causing coherent interference or destructive interference to occur between the light beams reflected by each reflector in the dimming subarea, thereby obtaining at least two light beam subareas corresponding one-to-one to the at least two dimming subareas, and the light intensities of the at least two light beam subareas are different; the dimming condition of the image to be projected indicates the brightness requirement of each image subarea in the image to be projected; a light valve, configured to modulate the illumination light beam after being dimmed by the spatial light modulating device based on image information of the image to be projected; The lens is used to project the illumination light beam modulated by the light valve into an image.

2. The laser projection device according to claim 1, characterized in that: The spatial dimming device is configured to adjust, based on brightness information of each image subarea in the image to be projected, the positions of the respective reflectors in the first dimming subarea through the respective position adjustment components in the first dimming subarea, so that at least a portion of the light in the first light beam subarea reflected by the reflectors in the first dimming subarea undergoes coherent interference; and to adjust, through the respective position adjustment components in the second dimming subarea, the positions of the respective reflectors in the second dimming subarea, so that at least a portion of the light in the second light beam subarea reflected by the reflectors in the second dimming subarea undergoes destructive interference; Wherein, in the image to be projected, the brightness of a first image subarea corresponding to the first dimming subarea is greater than the brightness of a second image subarea corresponding to the second dimming subarea.

3. The laser projection device according to claim 1, characterized in that: The position adjustment assembly includes: a first substrate and a second substrate arranged opposite to each other, and a driving structure located between the first substrate and the second substrate; The reflector is located on a side of the second substrate away from the first substrate; The driving structure is used to drive the second substrate to move in a direction perpendicular to the second substrate.

4. The laser projection device according to claim 3, characterized in that: The driving structure includes: at least one driving electrode located on a side of the first substrate close to the second substrate, a common electrode located on a side of the second substrate close to the first substrate, and a plurality of elastic supporting members located between the first substrate and the second substrate; One end of the elastic support member is fixedly connected to the driving electrode, and the other end is fixedly connected to the common electrode; The driving structure is used to adjust the distance between the first substrate and the second substrate by applying the same voltage as the common electrode or a different voltage from the common electrode to each of the driving electrodes.

5. The laser projection device according to claim 4, characterized in that: The driving structure further includes a driving circuit connected to each of the driving electrodes.

6. The laser projection device according to claim 4, characterized in that: The at least one driving electrode includes: a plurality of nested annular driving electrodes, and a plate-shaped driving electrode located in a central area of the plurality of annular driving electrodes.

7. A projection method of a laser projection device, characterized in that: The method is applied to the laser projection device according to any one of claims 1 to 6, and the method comprises: Determining at least two image partitions in the image to be projected that correspond one-to-one to at least two dimming partitions of the spatial dimming device; Based on the brightness information of the at least two image subareas, a dimming condition of the image to be projected is determined from a plurality of dimming conditions; and according to the dimming condition of the image to be projected, for any dimming subarea, positions of the respective reflectors in a direction perpendicular to the reflective surfaces of the reflectors are adjusted by respective position adjustment components within the any dimming subarea, and the reflectors are controlled to rotate along the diagonal directions thereof, so that the phases of at least part of the light in the illumination light beam reflected by the respective reflectors within the any dimming subarea are different, thereby causing coherent interference or destructive interference to occur between the light beams reflected by the respective reflectors within the dimming subarea, thereby obtaining at least two light beam subareas corresponding one-to-one to the at least two dimming subareas, and the light intensities of the at least two light beam subareas being different; the dimming condition of the image to be projected indicates the brightness requirements of the respective image subareas in the image to be projected; Based on the image information of the image to be projected, modulating the illumination light beam after being dimmed by the spatial light modulating device through a light valve; The illumination light beam modulated by the light valve is projected into an image through a lens.

8. A laser projection system, characterized in that: include: A projection screen and the laser projection device according to any one of claims 1 to 6.

Images