WO2021143441A1 - 光源调制系统、方法及光源系统 - Google Patents

光源调制系统、方法及光源系统 Download PDF

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WO2021143441A1
WO2021143441A1 PCT/CN2020/137113 CN2020137113W WO2021143441A1 WO 2021143441 A1 WO2021143441 A1 WO 2021143441A1 CN 2020137113 W CN2020137113 W CN 2020137113W WO 2021143441 A1 WO2021143441 A1 WO 2021143441A1
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Prior art keywords
light
image
brightness
modulator
spatial
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PCT/CN2020/137113
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English (en)
French (fr)
Inventor
赵鹏
吴超
余新
李屹
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深圳光峰科技股份有限公司
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Publication of WO2021143441A1 publication Critical patent/WO2021143441A1/zh

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/206—Control of light source other than position or intensity
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141—Constructional details thereof
    • H04N9/315—Modulator illumination systems
    • H04N9/3155—Modulator illumination systems for controlling the light source

Definitions

  • Directly increasing the brightness of the light source itself including increasing the number of light sources, or increasing the current through the light source to increase the brightness of a single light source, etc.
  • the solution of directly increasing the brightness of the light source will increase the cost of the projector, and will also increase the heat of the whole machine, resulting in increased heat dissipation pressure.
  • the increase in the brightness of the light source often leads to an increase in the optical extension of the light source.
  • the optical extension will be limited by components such as the optical machine and modulator. Therefore, there is an upper limit for increasing the brightness of the light source.
  • This application mainly provides a light source modulation system, method, and light source system to recycle OFF light to increase light energy utilization efficiency and improve the brightness of the projection screen.
  • the present application provides a light source modulation system, including a first spatial light modulator, a light splitting element, a second spatial light modulator, and a light combining element;
  • the first spatial light modulator is used for The incident light source is modulated to form the first image light and generate OFF light;
  • the light splitting element is used to separate the optical paths of the first image light and the OFF light, and guide the first image light to the combined light Element, and guide the OFF light to the second spatial light modulator;
  • the second spatial light modulator modulates the OFF light to form a second image light;
  • the light combining element combines the first The image light is combined with the second image light.
  • the first spatial light modulator is an LCD panel without the analyzer; the second spatial light modulator is one of DMD, LCD, and LCOS.
  • the light modulation system further includes a modulation function input module, the modulation function input module is used to control the modulation function of the first spatial light modulator and the second spatial light modulator, so that the second spatial light modulator The light modulator generates the least OFF light.
  • the present application also provides a light source modulation method, including: Step S1: modulate the light source light incident on the first spatial light modulator according to the image signal to generate first image light and OFF light; Step S2: according to The image signal modulates the OFF light incident to the second spatial light modulator to generate second image light; step S3: the first image light and the second image are combined with light and then output.
  • the light source modulation method further includes: Step S21: In the current pixel, obtain the OFF light intensity incident on the second spatial light modulator; Step S22: Determine the brightness of the first image and the total light intensity. Whether the sum of the brightness of the second image is greater than the brightness of the OFF light incident to the second spatial light modulator; step S23: if the sum of the brightness of the first image and the brightness of the second image is greater than or equal to the incident To the OFF light intensity of the second spatial light modulator, the second image light intensity is updated to the OFF light intensity incident on the second spatial light modulator, and the first image light intensity is updated to the The difference between the sum of the brightness of the first image and the brightness of the second image and the brightness of the OFF light incident on the second spatial light modulator; step S24: if the brightness of the first image and the brightness of the second image are If the sum of brightness is less than the brightness of the OFF light incident to the second spatial light modulator, the brightness of the second image is updated to the sum of
  • step S29 determine whether the preset condition is satisfied; if so, repeat steps S21-S28.
  • the preset condition includes: OFF light output by the second spatial light modulator is greater than a preset value.
  • each sub-pixel in the image frame calculate the first modulation function of the first spatial light modulator according to the brightness of the first image, and calculate the second spatial light modulation according to the brightness of the second image
  • the second modulation function of the device the first spatial light modulator modulates the light source light according to the first modulation function, and the second spatial light modulator modulates the light incident on the second spatial light according to the second modulation function
  • the light of the modulator is modulated.
  • the present application also provides a light source system including a multi-color light source, and a light source of at least one color among the multi-color light sources adopts the light source modulation system and light source modulation method described above for light source modulation.
  • the multi-color light source is a red, green and blue light source.
  • the beneficial effect of the present application is that the dual spatial light modulator light source modulation system provided by the present application is used to reuse the OFF light output by the first spatial light modulator, which improves the efficiency of light energy utilization, and under the premise of the same light source brightness , Can achieve better screen display brightness, and at the same time, because the OFF light is used for display, the heat generated by the OFF light is reduced, and the heat dissipation pressure of the whole machine is reduced.
  • the OFF light generated by the second spatial light modulator can be reduced, and the light energy utilization rate can be further improved.
  • FIG. 1 is a schematic diagram of the optical path for separating OFF light for different spatial light modulators in this application;
  • Fig. 2 is a schematic block diagram of the optical path of the light source modulation system in the present application
  • FIG. 3 is a schematic diagram of an optical path in which the first spatial light modulator is an LCD and the second spatial light modulator is a DMD in an embodiment of the present application;
  • Fig. 4 is a schematic diagram of the optical path of multiplexing a PBS when the first and second spatial light modulators in the embodiment of the present application are both LCDs;
  • FIG. 5 is a schematic diagram of the light path of the light source system in an embodiment of the present application.
  • Fig. 6 is a schematic diagram of the light path of the light source system in another embodiment of the present application.
  • Fig. 7 is a flowchart of a light source modulation method in the first embodiment of the present application.
  • FIG. 8 is a flowchart of a light source modulation method in the second embodiment of the present application.
  • Figure 9a/9b is an example diagram of light source modulation in this application.
  • FIG. 10 is a schematic diagram of the image brightness effect using the light source modulation method in this application.
  • Figure 1(a) is a schematic diagram of the LCD device.
  • 101 is a polarizer, which provides a specific beam polarization to ensure that the polarization state of the incident light 104 after passing through meets the requirements of the subsequent device.
  • 103 is a liquid crystal layer.
  • the polarization state of the incident light 104 can be controlled differently to obtain the two components of the beam 106 and the beam 105.
  • the two parts of the beam have different polarization states.
  • 102 is the analyzer, which can change the polarization state of the specific polarization.
  • the light beam 106 is filtered out to form image light
  • the light beam 105 filtered by the analyzer is the OFF light corresponding to the LCD device, and the OFF light can be drawn out by removing the analyzer 102.
  • Figure 1(b) is a schematic diagram of a DMD device
  • 11 is DMD
  • 112 is a TIR prism usually used with DMD
  • incident light 114 is incident from the side of TIR
  • image light 115 generated by DMD is emitted from the front of TIR
  • OFF light 116 There is a certain angle with the image light
  • an optical dump device 113 is usually used to process the OFF light.
  • Figure 1(c) is a schematic diagram of an LCOS device
  • 12 is an LCOS device
  • 132 is a PBS prism usually used in conjunction with LCOS.
  • the incident light 133 has a p-polarization state, so it can pass through the PBS and enter the LCOS, and then the polarization state will be changed by the LCOS.
  • the p-polarized 135 and s-polarized 134,134 light is reflected by the PBS to become image light, while 135 is the OFF light, which is transmitted from the PBS back to the incident light orientation.
  • the incident light is perpendicular to the LCOS
  • the OFF light and the incident light The direction is opposite, the position coincides, and separation is more difficult. Therefore, in order to separate the OFF light and the incident light in space, the incident light and the LCOS can be set at an angle.
  • FIG. 2 is a schematic block diagram of the optical path of the light source modulation system in this application.
  • the light source modulation system includes a first spatial light modulator 201, a light splitting element 202, a light homogenizing element 203, a second spatial light modulator 204, and a light combining element 205.
  • the uniform light source light enters the first spatial modulator 201, and the first spatial light modulator 201 modulates the light source light according to its modulation function to generate first image light and OFF light.
  • the OFF light when incident on the second spatial light modulator 204, it first passes through the light homogenizing element 203 for homogenization.
  • the present application directs the OFF light generated by the first spatial light modulator to the second spatial light modulator for modulation to generate the second image light. , And then photosynthesize with the first image generated by the first spatial light modulator to output light, which can greatly increase the utilization rate of light energy and increase the brightness of the image.
  • the second spatial light modulator since the second spatial light modulator generates OFF light when it modulates the second image light, according to the inventive concept of this application, those skilled in the art can easily think of adding another spatial light modulator to the second space.
  • the OFF light generated by the light modulator is modulated and reused. This solution does not exceed the inventive concept of this application and belongs to the scope of patent protection of this application.
  • FIG. 3 shows a schematic diagram of the light path of the light source modulation system in an embodiment of the application.
  • the first spatial light modulator 301 is an LCD without the analyzer
  • the second spatial light modulator is a DMD.
  • the second spatial light modulator may also be an LCD device or an LCOS device.
  • the light source modulation system includes LCD301 without the analyzer, polarization beam splitter 302, homogenizing element 303, DMD304, polarization combining sheet 305, and reflecting sheet 306.
  • the first image light 308 in the P (or S) polarization state and the OFF light 309 in the S (or P) polarization state are output.
  • the OFF light 309 is homogenized by the light homogenizing element 303 and then incident to the DMD304 , DMD304 modulates the OFF light and outputs the second image light 311.
  • FIG. 4 shows a schematic diagram of the light path of the light source modulation system in another embodiment of the application.
  • the light source modulation system includes LCD401, LCD402, polarization combining and beam splitter PBS403, reflector 4041/4042/4043, lens 4051/4052, and fly-eye lens 406 without the analyzer.
  • the uniform light source light 411 is incident on the LCD 401 and then modulated to produce the first image light 413 and the OFF light 412.
  • the polarization beam splitter 403 reflects the first image light 413 and transmits the OFF light 412.
  • the OFF light 412 is collimated and condensed by the lens 4051
  • the reflection sheet 4043 reflects to the fly-eye lens 406, the fly-eye lens 406 homogenizes the OFF light 412 and then outputs it to the reflection sheet 4042.
  • the reflection sheet 4042 outputs the homogenized OFF light to the lens 4052, and the lens 4052 collimates the OFF light After being converged, it is reflected by the reflective sheet 4041 to the LCD 402, and the LCD 402 modulates the OFF light.
  • a half-wave plate can be added to the optical path where the OFF light enters the polarization beam splitter PBS403 to change the polarization state of the OFF light, so that the OFF light can be transmitted.
  • the half-wave plate can be added on the incident light path of the LCD402 or on the exit light path of the LCD402.
  • the second image light 414 is transmitted through the polarization combining and splitting sheet PBS403 and then combined with the first image light 413 to form the final image 415.
  • the split of the first image light and the OFF light, and the combined light of the first image light and the second image light are multiplexed with the same PBS prism, so that the volume of the light source can be reduced.
  • the LCD 401 in this embodiment can be replaced by a spatial light modulator that also outputs polarized image light and OFF light, such as LCOS; the LCD 402 can be replaced by any other form of spatial light modulator.
  • the fly-eye lens 406 can be replaced with other light homogenizing devices, such as square rods.
  • FIG. 5 shows an optical path diagram of the light source system in an embodiment of the application.
  • the colored arrow lines in this figure indicate the light of the corresponding light source and are not regarded as a restriction on the light path.
  • the input light source is white light, that is, a multi-color light source with a mixture of red, yellow, and blue.
  • the light source system includes a first dichroic plate 501, a second dichroic plate 502, a blue spatial light modulator 503, a green spatial light modulator 504, a lens 5051-5052, a reflective plate 5061/5062/5063, and a dichroic cube device 507 , Light modulation system 508.
  • the white light source is incident on the first beam splitter 501, the first beam splitter reflects blue light and transmits yellow light, and the reflected blue light enters the blue spatial light modulator 503, and is modulated and output through the dichroic cube device 507.
  • the yellow light transmitted by the first beam splitter 501 includes red light and green light components.
  • the second beam splitter reflects green light and transmits red light.
  • the reflected green light is modulated by the green spatial light modulator 504 and then passed through the dichroic cube device. Output after 507.
  • the red light transmitted by the second beam splitter 502 is condensed by the lens 5051 and then reflected by the reflection sheets 5061 and 5062, condensed by the lens 5052, and reflected by the 5063 and enters the light modulation system 508 for modulation.
  • the light modulation system 508 is the light modulator system in the embodiment of the application.
  • the first image light generated after the incident red light is modulated by the first spatial light modulator 5081 is reflected by the PBS cube 5082 to the dichroic cube device 507 and then output.
  • the OFF light generated by the first spatial light modulator 5081 is transmitted by the PBS cube 5082 and then enters the second spatial light modulator 5083 through the subsequent optical path.
  • the second spatial light modulator 5083 modulates the OFF light and outputs the second image light.
  • the second image light is transmitted through the PBS cube 5082 and then output through the color separation cube 507.
  • the first spatial light modulator is an LCD with the analyzer removed
  • the second spatial light modulator is an LCD, and a half-wave plate is added to the optical path of the OFF light incident on the PBS cube 5082 to change its polarization state. It should be noted that without creative work, the first spatial light modulator and/or the second spatial light modulator can be replaced with other types of modulators by making adaptive modifications to the optical path.
  • the light energy utilization rate of the red light can be improved, and the brightness of the red light can be improved.
  • the light source modulation system can also be used in light paths of other colors.
  • FIG. 6 shows a schematic diagram of the light path of the light source system in another embodiment of the application.
  • the colored arrow lines in this figure indicate the light of the corresponding light source, and are not regarded as a restriction on the light path.
  • the input light source is white light, that is, a multi-color light source with a mixture of red, yellow, and blue.
  • the light source system includes a first beam splitter 601, a second beam splitter 602, a first polarization beam splitting prism 603, a 1/2 wave plate 604, a first lens 611, a fly-eye lens 608, a second lens 612, a second polarization beam splitting prism 609,
  • the LCD610, PBS cube 613, LCD614, blue spatial light modulator 605, green spatial light modulator 606, and color separation cube 607 of the analyzer are removed.
  • the uniform light source light enters the first beam splitter 601, the first beam splitter 601 reflects blue light and transmits red and green light, and the reflected blue light enters the blue spatial light modulator 605, and is modulated and output through the dichroic cube device 607.
  • the second beam splitter 602 reflects green light and transmits red light, and the reflected green light is modulated by the green spatial light modulator 606, and then output after the dichroic cube device 607. Taking the red light of the P polarization state as an example for description, the red light of the P polarization state is transmitted through the second beam splitter 602, and then enters the first polarization beam splitting prism 603.
  • the first polarization beam splitting prism 603 transmits P polarized light and reflects S polarized light.
  • the red light in the P polarization state is transmitted through the first polarization beam splitting prism 603 and then enters the 1/2 wave plate 604.
  • the 1/2 wave plate 604 converts the red light in the P polarization state into light in the S polarization state through the lens 611
  • the collimating, fly-eye lens 608 homogenizes the light, and the lens 612 converges and then enters the second polarization beam splitting prism 609.
  • the second polarization beam splitting prism 609 has the characteristics of reflecting S-polarized light and transmitting P-polarized light.
  • the incident S-polarized red light The first image light in the P polarization state and the OFF light in the S polarization state are generated after being reflected to the LCD 610, modulated by the LCD 610, and both enter the PBS cube 613 that transmits P polarization light and reflects S polarization light.
  • the first image light in the P polarization state is transmitted through the PBS cube 613 and then output from the dichroic cube device 607.
  • the OFF light in the S polarization state is reflected by the PBS cube 613 and enters the first polarization beam splitting prism 603, where it is transmitted by the first polarization beam splitting prism 603 Reflected, incident on the 1/2 wave plate 604, converted into P-polarized light, when incident on the second polarizing beam splitter 609, transmitted through the second polarizing beam splitter 609 and incident on the LCD614, after being modulated by the LCD614, a S-polarized light
  • the second image light is reflected by the dichroic cube device 607 and then photosynthesized with the first image light to be output.
  • FIG. 7 is a flowchart of a light source modulation method in an embodiment provided by this application.
  • Light source modulation methods include:
  • Step S1 modulate the light source light incident to the first spatial light modulator according to the image signal to generate first image light and OFF light;
  • Step S2 modulate the OFF light incident to the second spatial light modulator according to the image signal to generate second image light;
  • Step S3 The first image light and the second image light are photosynthesized and then output.
  • Both the first spatial light modulator and the second spatial light modulator modulate the incident light according to the image signal, so as to ensure that the brightness ratio of each pixel in the image light generated after the first image light and the second image light are combined does not change.
  • the image display will not be distorted.
  • step S2 if the loss of light energy by the device is not considered, all OFF light generated by the first spatial light modulator is incident on the second spatial light modulator as the source light of the second spatial light modulator.
  • the OFF light generated by the first spatial light modulator is homogenized before being incident on the second spatial light modulator. At this time, it is incident on each pixel of the second spatial light modulator.
  • the OFF light brightness is the same; in another embodiment, a corresponding device is added between the first spatial light modulator and the second spatial light modulator so that the OFF light brightness incident on each pixel of the second spatial light modulator is different, for example Add a device that can realize local dimming (local dimming) between the first spatial light modulator and the second spatial light modulator, so that the OFF light generated by the first spatial light modulator is incident on the second spatial light modulator.
  • the modulator is arranged according to the brightness of the image signal.
  • the inventive concept of this embodiment is: under the condition that the image brightness ratio remains unchanged, the brightness of the image light is provided by the second spatial light modulator as much as possible, thereby reducing the amount of OFF light generated by the second spatial light modulator to the maximum Utilize the light energy utilization rate of the light source to improve the brightness of the image.
  • Step S1 modulate the light source light incident to the first spatial light modulator according to the image signal to generate the first image light and the OFF light; the brightness of the first image light in the current pixel is L1 and the brightness of the OFF light is L2;
  • Step S2 modulate the OFF light incident to the second spatial light modulator according to the image signal to generate the second image light; the brightness of the second image light in the current pixel is L3;
  • Step S21 In the current pixel, obtain the OFF light brightness L21 incident on the second spatial light modulator;
  • Step S22 Determine whether the sum of the first image light luminance L1 and the second image light luminance L3 is greater than the OFF light luminance L21 incident on the second spatial light modulator;
  • Step S23 If the sum of the first image light intensity L1 and the second image light intensity L3 is greater than or equal to the OFF light intensity L21 incident on the current pixel of the second spatial light modulator, that is, when L1+L3 ⁇ L21, change the second space
  • Step S24 If the sum of the first image light intensity L1 and the second image light intensity L3 is less than the OFF light intensity L21 incident on the current pixel of the second spatial light modulator, that is, when L1+L3 ⁇ L21, then the second spatial light
  • the brightness L1 is updated to zero.
  • Step S27 modulate the incremental OFF light incident to the second spatial light modulator according to the image signal to obtain the incremental brightness L22;
  • Step S3 The first image light and the second image light are photosynthesized and then output.
  • This embodiment adjusts the contribution of the first spatial light modulator and the second spatial light modulator to the image brightness under the premise of maintaining the brightness of the output image of the first embodiment, and calculates the first spatial light modulation after the adjustment
  • the OFF light output is increased by the first spatial light modulator
  • the OFF light increment input to the second spatial light modulator is obtained according to the OFF light output increased by the first spatial light modulator
  • the OFF light increment is modulated again according to the image signal, thereby increasing
  • the brightness of the second image light is increased, thereby increasing the brightness of the output image light.
  • the above content describes the process of light modulation of a pixel. Therefore, unless otherwise specified, the "brightness” refers to the brightness of the current pixel.
  • the pixel if the first image light corresponding to the first spatial light modulator is zero, it means that the pixel is in a fully closed state during the modulation period of the first spatial light modulator.
  • the brightness value on the right side of the equation is the brightness value updated by this method
  • the brightness value on the left side of the equation is the brightness value before being updated by this method.
  • the brightness value of each pixel in the first image light can be calculated, based on which the first modulation function of the first spatial light modulator can be obtained, and the first spatial light modulator modulates the light source light according to the modulation function.
  • the first image light is generated.
  • the brightness value of each pixel on the second image light is also calculated.
  • the second modulation function of the second spatial light modulator can be obtained.
  • the second spatial light modulator is incident on the second image light according to the second modulation function.
  • Two spatial light modulators modulate the light.
  • the light incident to the second spatial light modulator may be light generated after homogenizing the OFF light generated by the first spatial light modulator, or may be other processing performed on the OFF light generated by the first spatial light modulator. (Such as local dimming).
  • it may also include:
  • Step S29 Determine whether the preset condition is met; if so, repeat steps S21-S28. If not, directly use the first modulation function calculated from the brightness of each pixel of the current first spatial light modulator to modulate the light source light, and use the second modulation function calculated from the brightness of each pixel of the second spatial light modulator to input the The light to the second spatial light modulator is modulated.
  • the preset condition may be to determine whether the OFF light output by the second spatial light modulator is greater than a preset value.
  • the OFF light output by the second spatial light modulator is also different when the light source is maximized. Therefore, the size of the preset value can be obtained in advance through simple limited repeated experiments, and a table can be established to set different preset values of OFF light output by the second spatial light modulator according to the image signal.
  • the judgment may not be performed, and steps S21-S28 are repeated once after modulating the increased OFF light.
  • Both the light source modulation system and the light source system in this application can adopt the light source modulation method in this embodiment, and for the sake of brevity, the details will not be repeated.
  • the brightness of the pixels on the second spatial light modulator is not only related to the brightness of the image signal to be displayed, but also related to the OFF light generated by all pixels of the first spatial light modulator.
  • the following uses two pixels A and B as an example to describe the modulation method in this embodiment:
  • the brightness of the image signal to be displayed by the pixel A and the pixel B are 0.1 and 0.7, respectively. That is, when one spatial light modulator is used, the brightness of pixels A and B are 0.1 and 0.7, respectively.
  • the first spatial light modulator modulates the light source light incident on it according to the image signal.
  • using a dual spatial light modulator to modulate the light source can improve the brightness of the output image light.
  • the total brightness of the output image light is still pixel A: 0.16 and pixel B: 1.12.
  • each pixel in the image frame is processed separately.
  • the second modulation function is updated according to the updated brightness of the second image light pixel, and the second spatial light modulator modulates the OFF light incident to the second spatial light modulator according to the updated second modulation function.
  • the relationship between the brightness of pixels A and B and the brightness of OFF light input to the pixels A and B of the second spatial light modulator can be judged again.
  • the conditions are preset, repeat the above process.
  • FIG. 10 shows the effect of the light modulation method in the application on the improvement of image brightness.
  • Curve 1 is the distribution curve of the original image's brightness (that is, the image light output after using a single spatial light modulator)
  • curve 2 is the use of the dual spatial light modulation system in this application and the light source modulation method in the first embodiment
  • the brightness distribution curve of the image light after the light source is modulated
  • curve 3 is the brightness distribution curve after the image is modulated by the light source modulation method in the second embodiment of the present application.

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Abstract

一种光源调制系统、方法及光源系统，光源调制系统包括第一空间光调制器（201）、分光元件（202）、第二空间光调制器（204）、合光元件（205）；第一空间光调制器（201）用于对入射光源光进行调制形成第一图像光并产生OFF光；分光元件（202）用于将第一图像光与OFF光的光路分离，将第一图像光引导至合光元件（205）、并将OFF光引导至第二空间光调制器（204）；第二空间光调制器（204）对OFF光进行调制形成第二图像光；合光元件（205）将第一图像光与第二图像光进行合光。该光源调制系统及方法充分利用第一空间光调制器（201）产生的OFF光，从而提高了图像亮度和光能利用率。

Description

光源调制系统、方法及光源系统 技术领域
本申请涉及投影技术领域，特别是涉及一种光源调制系统、方法及光源系统。
背景技术
增加投影画面亮度的方法主要有两种，一种是直接增加光源本身的亮度，一种是增加光的利用效率。
直接增加光源本身的亮度，包括提高光源数量，或通过增大通过光源的电流来提高单个光源的亮度等。但直接增加光源亮度的方案会导致投影机成本增加，还会增加整机发热，导致散热压力增加。同时由于光源亮度的增加往往会导致光源光学扩展量的增加，在实际使用中光学扩展量会受到光机、调制器等部件的限制，因此，增加光源亮度也存在上限。
增加光的利用效率，大体上分为两种，一种是光回收方案，利用调制器产生图像时剩余的OFF光，将这部分光能重新利用起来，增加光能的利用效率。另一种是光转向技术，利用一个预调制器将光能按照图像的亮度分布进行重新排布，将光能汇聚到图像中的高亮区域，提升光能的利用效率，从而起到更高亮度的投影效果。但光转向技术依赖于一个额外的预调制器，增加了成本，而且目前主流的光转向技术都是采用相位空间光调制器实现，但这种器件目前尚不成熟，未大规模进行商业应用。
发明内容
本申请主要提供一种光源调制系统、方法及光源系统，以回收利用OFF光增加光能利用效率，提高投影画面亮度。
为解决上述技术问题，一方面，本申请提供一种光源调制系统，包括第一空间光调制器、分光元件、第二空间光调制器、合光元件；所述第一空间光调制器用于对入射光源光进行调制形成第一图像光并产生OFF光；所述分光元件用于将所述第一图像光与所述OFF光的光路分离，将所述第一图像光引导至所述合光元件、并将所述OFF光引导至所述第二空间光调制器；所述第二空间光调制器对所述OFF光进行调制形成第二图像光；所述合光元件将所述第一图像光与所述第二图像光进行合光。
在一种实施方式中，还包括匀光元件，所述匀光元件设置在所述分光元件与所述第二空间光调制器之间的光路上，用于对所述第一空间光调制器产生的OFF光进行匀光。
一种实施例中，所述第一空间光调制器为去掉检偏器的LCD面板；所述第二空间光调制器为DMD、LCD、LCOS中的一种。
有一种实施例中，所述分光元件与所述合光元件复用同一PBS棱镜。
进一步地，光调制系统还包括调制函数输入模块，所述调制函数输入模块用于控制所述第一空间光调制器及所述第二空间光调制器的调制函数，以使得所述第二空间光调制器产生的OFF光最少。
另一方面，本申请还提供一种光源调制方法，包括：步骤S1：根据图像信号对入射至第一空间光调制器的光源光进行调制，产生第一图像光及OFF光；步骤S2：根据图像信号对入射至第二空间光调制器的OFF光进行调制，产生第二图像光；步骤S3：将所述第一图像光与所述第二图像光合光后输出。
进一步地，所述光源调制方法在步骤S2之后还包括：步骤S21：在当前像素中，获得入射至第二空间光调制器的OFF光亮度；步骤S22：判断所述第一图像光亮度与所述第二图像光亮度之和是否大于所述入射至第二空间光调制器的OFF光亮度；步骤S23：若所述第一图像光亮度与第二图像光亮度之和大于或等于所述入射至第二空间光调制器的OFF光亮度，则将所述第二图像光亮度更新为所述入射至第二空间光调制器的OFF光亮度，将所述第一图像光亮度更新为所述第一图像光亮度与所述第二图像光亮度之和与所述入射至第二空间光调制器的OFF光亮度的差值；步骤S24：若所述第一图像光亮度与第二图像光亮度之和小于所述入射至第二空间光调制器的OFF光亮度，则将所述第二图像光亮度更新为所述第一图像光亮度与所述第二图像光亮度之和，将所述第一图像光亮度更新为零；步骤S25：计算此时所述第一空间光调制器产生的OFF光增量；步骤S26：根据所述第一空间光调制器产生的OFF光增量计算入射至第二空间光调制器的OFF光增量；步骤S27：根据图像信号对所述入射至第二空间光调制器的OFF光增量进行调制获得增量亮度；步骤S28：将所述第二图像光亮度更新为第二图像光亮度与增量亮度之和。
在一种实施例中，进一步地，步骤S29：判断是否满足预设条件；若是，则重复进行步骤S21-S28。
在一种实施方式中，所述预设条件包括：所述第二空间光调制器输出的OFF光大于预设值。
在另一种实施例中，在所述步骤S28后还包括：重复进行步骤S21-S28一次。
根据上述方法对图像帧中每个子像素进行处理：根据所述第一图像光亮度计算出第一空间光调制器的第一调制函数，根据所述第二图像光亮度计算出第二空间光调制器的第二调制函数；所述第一空间光调制器 根据所述第一调制函数对光源光进行调制，所述第二空间光调制器根据所述第二调制函数对入射至第二空间光调制器的光进行调制。
另一方面，本申请还提供一种光源系统，包括多色光源，所述多色光源中至少有一种颜色的光源采用上述光源调制系统及光源调制方法进行光源调制。
一种实施例中，所述多色光源为红绿蓝三色光源。
本申请的有益效果是：采用本申请提供的双空间光调制器光源调制系统，将第一空间光调制器输出的OFF光再次进行利用，提高了光能利用效率，在同等光源亮度的前提下，可以实现更好的画面显示亮度，同时因为利用OFF光进行显示，减少了OFF光产生的热量，减轻了整机的散热压力。
另外，采用本申请的光源调制方法，在上述光源调制系统的基础上可以减少第二空间光调制器产生OFF光，进一步提高光能利用率。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图，其中：
图1是本申请中针对不同的空间光调制器分离OFF光的光路示意图；
图2是本申请中光源调制系统的光路示意框图；
图3是本申请实施例中第一空间光调制器为LCD、第二空间光调制器为DMD的光路示意图；
图4是本申请实施例中第一、二空间光调制器均为LCD时复用一 个PBS的光路示意图；
图5是本申请一种实施例中光源系统的光路示意图；
图6是本申请另一种实施例中光源系统的光路示意图；
图7是本申请第一实施例中光源调制方法的流程图；
图8是本申请第二实施例中光源调制方法的流程图；
图9a/9b是本申请中光源调制的示例图；
图10是采用本申请中光源调制方法图像亮度效果示意图。
具体实施方式
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅是本申请的一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
在本文中提及“实施例”意味着，结合实施例描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其他实施例互斥的独立的或备选的实施例。本领域技术人员显式地和隐式地理解的是，本文所描述的实施例可以与其他实施例相结合。
空间光调制器是指可以对光束进行调制的光电器件，在投影系统中广为使用的空间光调制器主要包括DMD、LCD和Lcos这三种。在使用空间光调制器产生画面时，空间光调制器对入射的均匀照明光进行调制，让产生画面的亮度部分进入后续的投影系统中，剩余部分——称之为OFF光——则被调制器上的吸收或被反射到其他方向上被light dump吸收，如图1所示。
图1(a)为LCD器件的示意图，101为起偏器，提供特定的光束偏 振，保证入射光104经过后的偏振态符合后级器件的要求，103为液晶层，通过对液晶层增加不同的电压，可以对入射光104的偏振态进行不同的控制，从而获得光束106和光束105两个分量，两个部分的光束具有的偏振态不同，102为检偏器，可以将具有特定偏振的光束106过滤出来，形成图像光，而被检偏器滤除的光束105，就是LCD器件对应的OFF光，可以通过将检偏器102去除而将OFF光引出来。
图1(b)为DMD器件的示意图，11为DMD，112为通常配合DMD使用的TIR棱镜，入射光114从TIR的侧边入射，通过DMD产生的图像光115从TIR前方出射，OFF光116与图像光存在一定的夹角，通常会使用一个optical dump器件113来进行OFF光的处理。
图1(c)为LCOS器件的示意图，12为LCOS器件，132为通常与LCOS配合使用的PBS棱镜，入射光133具有p偏振状态，因此可以通过PBS，入射到LCOS后，被LCOS更改偏振态，产生p偏振的135和s偏振的134，134光被PBS反射后成为图像光，而135为OFF光，从PBS透射回到入射光方位，当入射光与LCOS垂直时，OFF光与入射光方向相反，位置重合，分离较为困难，因此为了使得OFF光和入射光在空间上分离可将入射光与LCOS设置一个角度。
请参考图2，是本申请中光源调制系统的光路示意框图。光源调制系统包括第一空间光调制器201、分光元件202、匀光元件203、第二空间光调制器204、合光元件205。均匀的光源光入射至第一空间调制器201，第一空间光调制器201根据其调制函数对光源光进行调制，产生第一图像光及OFF光。分光元件202设置在第一空间光调制器的出光光路上，用于将第一图像光与OFF光的光路分离，并单独或者配合其他器件将第一图像光引导至合光元件205，将OFF光引导至第二空间光调制器204所在的光路。第二空间光调制器根据其调制函数对入射的OFF光 进行调制，形成第二图像光。第一图像光与第二图像光经过合光元件205合光后输出到镜头投影成像。
较佳地，OFF光在入射至第二空间光调制器204时首先经过匀光元件203进行匀光。
相比现有技术中，直接将第一空间光调制器产生的OFF丢弃的方案，本申请将第一空间光调制器产生的OFF光引导至第二空间光调制器进行调制产生第二图像光，然后与第一空间光调制器产生的第一图像光合光后输出，可以较大程度地提高光能利用率，提高图像亮度。
需要说明的是，由于第二空间光调制器在调制产生第二图像光时又会产生OFF光，根据本申请的发明构思，本领域技术人员容易想到再增加一片空间光调制器对第二空间光调制器产生的OFF光进行调制再利用的方案。该方案未超出本申请的发明构思，属于本申请的专利保护范围。
请参考图3，其中所示为本申请一种实施例中光源调制系统的光路示意图。在本实施例中，第一空间光调制器301为去掉检偏器的LCD、第二空间光调制器为DMD。需要说明的是，在本实施例中，第二空间光调制器也可以为LCD器件或LCOS器件。
光源调制系统包括去掉检偏器的LCD301、偏振分光片302、匀光元件303、DMD304、偏振合光片305、反射片306。光源光入射至LCD301被调制后，输出P(或S)偏振态的第一图像光308和S(或P)偏振态的OFF光309，OFF光309经匀光元件303匀光后入射至DMD304，DMD304对OFF光进行调制后输出第二图像光311，由于DMD对OFF光进行调制后不改变其偏振态，第二图像光311为S(或P)偏振态与第一图像光308的偏振态垂直。偏振态相互垂直的第一图像光308和第二图像光311经偏振合光片305合光后输出。
需要说明的是，本实施例中除了采用偏振分光合光的方式外，也可以采用其他方式进行分光与合光。
请参考图4，其中所示为本申请另一种实施例中光源调制系统的光路示意图。该光源调制系统包括去掉检偏器的LCD401、LCD402、偏振合光分光片PBS403、反射片4041/4042/4043、透镜4051/4052、复眼透镜406。均匀的光源光411入射至LCD401后被调制产生第一图像光413、及OFF光412，偏振合光分光片403反射第一图像光413透射OFF光412，OFF光412经透镜4051准直会聚后经反射片4043反射至复眼透镜406，复眼透镜406对OFF光412进行匀光后输出至反射片4042，反射片4042将经过匀光的OFF光输出至透镜4052，透镜4052对OFF光进行准直会聚后经反射片4041反射至LCD402，LCD402对OFF光进行调制。由于正常状态下的LCD面板会改变入射光的偏振态，因此，可以在OFF光入射至偏振合光分光片PBS403的光路上增设一个半波片以改变OFF光的偏振态，使得OFF光能透过偏振合光分光片PBS403，半波片可以增加在LCD402入射光路上，也可以增加在LCD402出射光路上。第二图像光414透射偏振合光分光片PBS403后与第一图像光413合光形成最后的图像415。
在本实施例中，第一图像光与OFF光的分光、第一图像光与第二图像光的合光复用同一个PBS棱镜，从而可以减小光源体积。
需要说明的是，本实施例中的LCD401可以替换为同样输出偏振图像光与OFF光的空间光调制器，如LCOS；LCD402可以替换为其他任何形式的空间光调制器。复眼透镜406可以更换为其他匀光器件，如方棒。
请参考图5，其中所示为本申请一种实施例中光源系统的光路图。需要说明的是，本图中有颜色的箭头线为相应光源光线示意，不视为对 光路的限制。在本实施例中输入的光源光为白光，即为红、黄、蓝混合的多色光源。光源系统包括第一分色片501、第二分色片502、蓝光空间光调制器503、绿光空间光调制器504、透镜5051/5052、反射片5061/5062/5063、分色立方器件507、光调制系统508。
白光光源入射至第一分光片501，第一分光片反射蓝光透射黄光，被反射的蓝光进入蓝光空间光调制器503，被调制后通过分色立方器件507输出。第一分光片501透射的黄光包括红光、绿光分量，第二分光片反射绿光、透射红光，被反射的绿光经绿光空间光调制器504调制后，经分色立方器件507后输出。第二分光片502透射的红光经透镜5051会聚后经反射片5061、5062反射、经透镜5052会聚、经5063反射后进入光调制系统508进行调制。光调制系统508为本申请实施例中的光调制器系统，入射的红光经第一空间光调制器5081调制后产生的第一图像光被PBS立方5082反射至分色立方器件507后输出，第一空间光调制器5081产生的OFF光被PBS立方5082透射后经过后续光路入射至第二空间光调制器5083，第二空间光调制器5083对OFF光进行调制后输出第二图像光，第二图像光经PBS立方5082透射后经分色立方器件507后输出。
第一空间光调制器为去掉检偏器的LCD，第二空间光调制器为LCD，并且在OFF光入射至PBS立方5082的光路上增加一个半波片以改变其偏振态。需要说明的是，在不付出创造性劳动的情况下，对光路做出适应性修改就可以将第一空间光调制器和/或第二空间光调制器替换为其他类型的调制器。
在本实施例中，通过对红光光路采用本申请中的光源调制系统，能够提高红光的光能利用率，提高红光亮度。也可以在其他颜色的光路中采用本光源调制系统。
请参考图6，其中所示为本申请另一种实施例中光源系统的光路示意图。需要说明的是，本图中有颜色的箭头线为相应光源光线示意，不视为对光路的限制。在本实施例中输入的光源光为白光，即为红、黄、蓝混合的多色光源。
光源系统包括第一分光片601、第二分光片602、第一偏振分光棱镜603、1/2波片604、第一透镜611、复眼透镜608、第二透镜612、第二偏振分光棱镜609、去掉检偏器的LCD610、PBS立方613、LCD614、蓝光空间光调制器605、绿光空间光调制器606、分色立方器件607。
均匀的光源光入射至第一分光片601，第一分光片601反射蓝光透射红光与绿光，被反射的蓝光进入蓝光空间光调制器605，被调制后通过分色立方器件607输出。第二分光片602反射绿光、透射红光，被反射的绿光经绿光空间光调制器606调制后，经分色立方器件607后输出。以P偏振态的红光为例进行说明，P偏振态的红光透射第二分光片602后，入射至第一偏振分光棱镜603，第一偏振分光棱镜603具有透射P偏振光反射S偏振光的特性，P偏振态的红光透射第一偏振分光棱镜603后入射至1/2波片604，1/2波片604将P偏振态的红光转换为S偏振态的光，经透镜611准直、复眼透镜608匀光、透镜612会聚后入射至第二偏振分光棱镜609，第二偏振分光棱镜609具有反射S偏振光透射P偏振光的特性，因此，入射的S偏振态的红光被反射至LCD610，经LCD610调制后产生P偏振态的第一图像光与S偏振态的OFF光，均入射至具有透射P偏振光反射S偏振光的PBS立方613。P偏振态的第一图像光经PBS立方613透射后从分色立方器件607输出，S偏振态的OFF光经PBS立方613反射后入射至第一偏振分光棱镜603，被第一偏振分光棱镜603反射，入射至1/2波片604，转换为P偏振态的光，入射至第二偏振分光棱镜609时，透射过第二偏振分光棱镜609入射至 LCD614，经LCD614调制后产生具有S偏振的第二图像光，经分色立方器件607反射后与第一图像光合光输出。
请参考图7，为本申请提供的一种实施例中光源调制方法的流程图。光源调制方法包括：
步骤S1：根据图像信号对入射至第一空间光调制器的光源光进行调制，产生第一图像光及OFF光；
步骤S2：根据图像信号对入射至第二空间光调制器的OFF光进行调制，产生第二图像光；
步骤S3：将所述第一图像光与所述第二图像光合光后输出。
第一空间光调制器与第二空间光调制器均根据图像信号对入射光进行调制，这样就可以保证第一图像光与第二图像光合光后产生的图像光中各个像素亮度比例不变，图像显示不会失真。
在步骤S2中，若不考虑器件对光能的损耗，第一空间光调制器产生的OFF光全部入射至第二空间光调制器，作为第二空间光调制器的源光。
需要说明的是，在一种实施方式中，第一空间光调制器产生的OFF光进行匀光后才入射至第二空间光调制器，此时入射至第二空间光调制器上各个像素的OFF光亮度相同；另一种实施方式中，在第一空间光调制器与第二空间光调制器之间增加相应器件使得入射至第二空间光调制器各个像素上的OFF光亮度不同，例如，在第一空间光调制器与第二空间光调制器之间增加一可以实现local dimming(局部减暗)功能的器件，使得第一空间光调制器产生的OFF光在入射至第二空间光调制器时根据图像信号亮度进行排布。
另外，在本申请实施例中以像素为单位进行光调制，第一空间光调制器与第一空间光调制器的像素一一对应，第一空间光调制器产生的第 一图像光与第二空间光调制器产生的第二图像光进行合光实际上是第一空间光调制器像素的亮度与第二空间光调制器对应像素亮度的叠加。
请参考图8，其中所示为本申请第二实施例中光源调制方法的流程图。
由于第一空间光调制器上的OFF光能被第二空间光调制器利用，在不考虑器件损耗的情况下基本上无光能损耗，但是，第二空间光调制器上还存在OFF光的输出，本实施例的发明构思为：在保证图像亮度比例不变的情况下，图像光的亮度尽量由第二空间光调制器提供，从而减少第二空间光调制器产生OFF光的量，最大化利用光源光能利用率，提升图像亮度。
下面为了便于对本实施例的方案进行描述，以第一空间光调制器产生的OFF光进行匀光后入射至第二空间光调制器为例进行说明，但不作为对本申请的限制：
步骤S1：根据图像信号对入射至第一空间光调制器的光源光进行调制，产生第一图像光及OFF光；当前像素中第一图像光的亮度为L1、OFF光的亮度为L2；
步骤S2：根据图像信号对入射至第二空间光调制器的OFF光进行调制，产生第二图像光；当前像素中第二图像光的亮度为L3；
步骤S21：在当前像素中，获得入射至第二空间光调制器的OFF光亮度L21；
在第一空间光调制器产生的OFF光进行匀光后入射至第二空间光调制器的情形下，若不考虑器件对光能的损耗，则入射至第二空间光调制器的OFF光亮度＝第一空间光调制器所有像素产生的OFF光亮度之和÷第二空间光调制器的像素个数N，L21＝∑L2÷N。
步骤S22：判断所述第一图像光亮度L1与所述第二图像光亮度L3之和是否大于所述入射至第二空间光调制器的OFF光亮度L21；
步骤S23：若第一图像光亮度L1与第二图像光亮度L3之和大于或等于入射至第二空间光调制器当前像素的OFF光亮度L21，即L1+L3≥L21时，将第二空间光调制器调制产生的第二图像光亮度L3更新为入射至第二空间光调制器当前像素的OFF光亮度L21，即L3＝L21；将第一空间光调制器调制产生的第一图像光亮度L1更新为第一图像光亮度L1与第二图像光亮度L3之和与所述入射至第二空间光调制器当前像素的OFF光亮度L21的差值，即L1＝L1+L3-L21。
步骤S24：若第一图像光亮度L1与第二图像光亮度L3之和小于入射至第二空间光调制器当前像素的OFF光亮度L21，即L1+L3＜L21时，则将第二空间光调制器调制产生的第二图像光亮度L3更新为第一图像光亮度L1与第二图像光亮度L3之和，即L3＝L1+L3；将第一空间光调制器调制产生的第一图像光亮度L1更新为零。
S25：计算此时第一空间光调制器产生的OFF光增量；
S26：根据第一空间光调制器产生的OFF光增量计算入射至第二空间光调制器的OFF光增量；
需要说明的是，在本步骤中仍然需要先计算图像帧中第一空间光调制器上每个像素产生的OFF光增量，计算出第一空间光调制器产生的总的OFF光增量后，再计算入射至第二空间光调制器每个像素上的OFF光增量；
步骤S27：根据图像信号对入射至第二空间光调制器的OFF光增量进行调制获得增量亮度L22；
步骤S28：将第二图像光亮度L3更新为第二图像光亮度L3与增量亮度L22之和，即L3＝L3+L22。
步骤S3：将所述第一图像光与所述第二图像光合光后输出。
本实施例在保持第一实施例输出图像光亮度的前提下，对第一空间 光调制器及第二空间光调制器对图像光亮度的贡献进行调整，并且在调整后计算第一空间光调制器增加输出的OFF光，根据第一空间光调制器增加输出的OFF光获得输入到第二空间光调制器上OFF光增量，并根据图像信号对该OFF光增量进行再次调制，从而增加了第二图像光的亮度，进而增加了输出图像光的亮度。
需要说明的是，上述内容描述的一个像素光调制的过程。因此，除非有特别说明，其中的“亮度”指的均为当前像素的亮度。
在当前像素中，若第一空间光调制器对应的第一图像光为零，则说明该像素在第一空间光调制器的调制期间处于全关闭状态。
另外，在步骤S23、S24、S28中等式右边的亮度值为采用本方法更新后的亮度值，等式左边的亮度值为采用本方法更新前的亮度值。
采用上述方法可以计算出第一图像光中每个像素的亮度值，据此可以获得第一空间光调制器的第一调制函数，第一空间光调制器根据该调制函数对光源光进行调制从而产生第一图像光。同理，第二图像光上每个像素的亮度值也计算出来了，据此可以获得第二空间光调制器的第二调制函数，第二空间光调制器根据第二调制函数对入射至第二空间光调制器的光进行调制。此处，入射至第二空间光调制器的光可以是对第一空间光调制器产生的OFF光匀光后产生的光，也可以是对第一空间光调制器产生的OFF光进行其他处理(如局部减暗)后产生的光。
进一步地，在第二实施例的基础上，还可以包括：
步骤S29：判断是否满足预设条件；若是，则重复步骤S21-S28。若否，则直接以当前第一空间光调制器各像素的亮度计算得到的第一调制函数对光源光进行调制，以第二空间光调制器各像素的亮度计算得到的第二调制函数对输入至第二空间光调制器的光进行调制。
一种实施例方式中，该预设条件可以是判断第二空间光调制器输出 的OFF光是否大于预设值。当然，对于不同的图像信号，在最大化利用光源的情况下，第二空间光调制器输出的OFF光也不尽相同。因此，可以预先通过简单有限次重复实验获得预设值的大小，建立一个表格，对照图像信号设定不同的第二空间光调制器输出OFF光的预设值。
本实施例中，对增加的OFF光进行调制后，获得了新的图像光亮度，通过设置进行迭代处理条件，判断是否需要进行迭代处理，从而可以进一步提高光能利用率。
在其他实施例中，也可以不进行判断，在对增加的OFF光进行调制后再重复进行一次步骤S21-S28。
本申请中的光源调制系统及光源系统均可以采用本实施例中的光源调制方法，为了行文简洁，不再进行赘述。
下面，举例说明本实施例中的光源调制方法：
由于图像处理中一般按图像帧对每个像素进行调制，第二空间光调制器上像素的亮度不仅与待显示的图像信号亮度相关还与第一空间光调制器所有像素产生的OFF光有关，下面以2个像素A、B为例进行本实施例中调制方法的说明：
请参考图9a，设光源光入射至第一空间光调制器像素A、B的亮度分别为1，像素A、像素B分别要显示的图像信号亮度为0.1、0.7。即，采用一个空间光调制器时像素A、B的亮度分别为0.1、0.7。
第一空间光调制器根据图像信号对入射其上的光源光进行调制，像素A需要显示的亮度为0.1，则像素A处对应的第一图像光亮度LA1＝0.1，第一空间光调制器产生的OFF光亮度LA2＝0.9，像素B处对应的第一图像光亮度LB1＝0.7，第一空间光调制器产生的OFF光亮度LB2＝0.3,此时，第一空间光调制器产生的OFF光总量为LA2+LB2＝1.2，由于第一空间光调制器产生的OFF光进行匀光处理后才输入到第二空 间光调制器上，因此，输入到第二空间光调制器像素A、B的光亮度为LA21＝LB21＝1.2/2＝0.6；即，在计算第一空间光调制器产生的OFF光总量时需要考虑每个像素产生的OFF光，然后计算输入到第二空间光调制器上的总OFF光亮，根据第二空间光调制器的分辨率，即要显示的像素个数，计算输入到第二空间光调制器上每个像素的OFF光亮度。
为了保证图像显示颜色不失真，第二空间光调制器也需要根据图像信号对输入到第二空间光调制器像素A的OFF光进行调制以产生第二图像光，像素A处显示亮度LA3＝0.1*0.6＝0.06，像素B处亮度显示亮度LB3＝0.7*0.6＝0.42；此时，
对于像素A，其亮度变为LA1+LA3＝0.1+0.06＝0.16；对于像素B，其亮度变为LB1+LB3＝0.7+0.42＝1.12。
因此，相对于单空间光调制器，采用双空间光调制器对光源进行调制可提高输出图像光的亮度。
进一步地，请参考图9b。
像素A的亮度0.16小于输入到第二空间光调制器像素A的OFF光亮度LA21＝0.6，则第一图像光在像素A处的亮度LA1＝0，第二图像光在像素A处的亮度LA3＝LA1+LA3＝0.16。
像素B的亮度为LB1+LB3＝0.7+0.42＝1.12大于输入到第二空间光调制器像素B的OFF光亮度LB21＝0.6，则第一图像光在像素B处的亮度LB1＝LB1+LB3-LB21＝0.7+0.42-0.6＝0.52，第二图像光在像素B处的亮度LB3＝输入到第二空间光调制器像素B的OFF光亮度LB21＝0.6。
此时，对于像素A：第一图像光亮度为LA1＝0，第二图像光亮度LA3＝0.16；对于像素B：第一图像光亮度LB1＝0.52，第二图像光亮度LB3＝0.6。输出图像光总亮度仍然为像素A：0.16，像素B：1.12。
进一步进行处理，此时，对于第一空间光调制器，在调整前其输出 的OFF光总量为1-0.1+1-0.7＝1.2，调整后其输出的OFF光总量为1-0+1-0.52＝1.48。因此，第一空间光调制器产生的OFF光总增量为1.48-1.2＝0.28，经匀光后，分别入射至第二空间光调制器像素A、像素B的OFF光增量为0.28/2＝0.14。
根据图像信号对上述OFF光增量进行调制，由于像素A处显示的亮度为0.1、像素B处显示的亮度为0.7，为了保证图像显示不失真，因此像素A的亮度增量LA22＝0.1*0.14＝0.014，像素B的亮度增量为LB22＝0.7*0.14＝0.098。
更新后，对于像素A第二空间光调制器调制产生的第二图像光亮度为LA3＝LA3+LA22＝0.16+0.014＝0.174；对于像素B第二空间光调制器调制产生的第二图像光亮度为LB3＝LB3+LB22＝0.6+0.0988＝0.6988。
此时，输出的图像光亮度，像素A：0+0.174＝0.174，像素B：0.52+0.698＝1.218。相对于图9a中的方法，本方法进一步提高了输出图像光的亮度。
采用上述方式，对图像帧中的每个像素分别进行处理。
根据更新后的第二图像光像素的亮度更新第二调制函数，第二空间光调制器根据更新后的第二调制函数对入射至第二空间光调制器的OFF光进行调制。
进一步地，由于进行上述操作后像素A、B的亮度发生了变化，可再次判断像素A、B的亮度与输入至第二空间光调制器像素A、B的OFF光亮度的关系后，在满足预设条件时，重复进行以上过程。
请参考图10，其中所示本是申请中光调制方法对图像亮度提升的效果图。其中曲线1为原图像的光亮度(亦即，采用单空间光调制器后输出的图像光)分布曲线，曲线2是采用本申请中双空间光调制系统以及第一实施例中的光源调制方法对光源进行调制后图像光的亮度分布曲 线，曲线3是采用本申请第二实施例中的光源调制方法对图像进行调制后的亮度分布曲线。从该图中可以看出本申请中的光源调制系统及第一实施例中的光源调制方法能提高图像亮度，而本申请第二实施例中的光源调制方法光源调制方法在第一实施例的基础上又能进一步提高图像亮度。
需要说明的是，本申请中的光调制方法均是在不考虑器件对光能损耗的条件进行说明的，实际应用中，考虑相关器件对光能的损耗从而对本申请中的光调制方法做出适应性修改是本来领域技术人员容易想到的方案，不需要付出创造性的劳动，仍属于本申请的专利保护范围。
以上所述仅为本申请的实施例，并非因此限制本申请的专利范围，凡是利用本申请说明书及附图内容所作的等效结构或等效流程变换，或直接或间接运用在其他相关的技术领域，均同理包括在本申请的专利保护范围内。

Claims (15)

  1. 一种光源调制系统，其特征在于，包括第一空间光调制器、分光元件、第二空间光调制器、合光元件；
    所述第一空间光调制器用于对入射光源光进行调制形成第一图像光并产生OFF光；
    所述分光元件用于将所述第一图像光与所述OFF光的光路分离，将所述第一图像光引导至所述合光元件、并将所述OFF光引导至所述第二空间光调制器；
    所述第二空间光调制器对所述OFF光进行调制形成第二图像光；
    所述合光元件将所述第一图像光与所述第二图像光进行合光。
  2. 如权利要求1所述的光源调制系统，其特征在于，还包括匀光元件，所述匀光元件设置在所述分光元件与所述第二空间光调制器之间的光路上，用于对所述第一空间光调制器产生的OFF光进行匀光。
  3. 如权利要求1所述的光源调制系统，其特征在于，所述第一空间光调制器为去掉检偏器的LCD面板；所述第二空间光调制器为DMD、LCD、LCOS中的一种。
  4. 如权利要求3所述的光源调制系统，其特征在于，所述分光元件与所述合光元件复用同一PBS棱镜。
  5. 如权利要求1-4任一项所述的光调制系统，其特征在于，还包括调制函数输入模块，所述调制函数输入模块用于调整所述第一空间光调制器及所述第二空间光调制器的调制函数，以使得所述第二空间光调制器产生的OFF光最少。
  6. 一种应用于权利要求1-5任一项所述的光调制系统的光源调制方法，其特征在于，包括：
    步骤S1：根据图像信号对入射至第一空间光调制器的光源光进行调制，产生第一图像光及OFF光；
    步骤S2：根据图像信号对入射至第二空间光调制器的OFF光进行调制，产生第二图像光；
    步骤S3：将所述第一图像光与所述第二图像光合光后输出。
  7. 如权利要求6所述的光源调制方法，其特征在于，所述光源调制方法在步骤S2之后还包括：
    步骤S21：在当前像素中，获得入射至第二空间光调制器的OFF光亮度；
    步骤S22：判断所述第一图像光亮度与所述第二图像光亮度之和是否大于所述入射至第二空间光调制器的OFF光亮度；
    步骤S23：若所述第一图像光亮度与第二图像光亮度之和大于或等于所述入射至第二空间光调制器的OFF光亮度，则将所述第二图像光亮度更新为所述入射至第二空间光调制器的OFF光亮度，将所述第一图像光亮度更新为所述第一图像光亮度与所述第二图像光亮度之和与所述入射至第二空间光调制器的OFF光亮度的差值；
    步骤S24：若所述第一图像光亮度与第二图像光亮度之和小于所述入射至第二空间光调制器的OFF光亮度，则将所述第二图像光亮度更新为所述第一图像光亮度与所述第二图像光亮度之和，将所述第一图像光亮度更新为零；
    步骤S25：计算此时所述第一空间光调制器产生的OFF光增量；
    步骤S26：根据所述第一空间光调制器产生的OFF光增量计算入射至第二空间光调制器的OFF光增量；
    步骤S27：根据图像信号对所述入射至第二空间光调制器的OFF光增量进行调制获得增量亮度；
    步骤S28：将所述第二图像光亮度更新为第二图像光亮度与增量亮度之和。
  8. 如权利要求7所述的光源调制方法，其特征在于，在所述步骤S28后还包括：
    步骤S29：判断是否满足预设条件；
    若是，则重复进行步骤S21-S28。
  9. 如权利要求8所述的光源调制方法，其特征在于，所述预设条件包括：所述第二空间光调制器输出的OFF光大于预设值。
  10. 如权利要求7所述的光源调制方法，其特征在于，在所述步骤S28后还包括：重复进行步骤S21-S28一次。
  11. 如权利要求6-10任一项所述的光源调制方法，其特征在于，所述第一空间光调制器出射的OFF光经匀光后入射至所述第二空间光调制器。
  12. 如权利要求6-10任一项所述的光源调制方法，其特征在于，所述第一空间光调制器出射的OFF光经局部减暗处理后入射至所述第二空间光调制器。
  13. 如权利要求6-10任一项所述的光源调制方法，其特征在于，根据上述方法对图像帧中每个像素进行处理：根据所述第一图像光亮度计算出第一空间光调制器的第一调制函数，根据所述第二图像光亮度计算出第二空间光调制器的第二调制函数；所述第一空间光调制器根据所述第一调制函数对光源光进行调制，所述第二空间光调制器根据所述第二调制函数对入射至第二空间光调制器的光进行调制。
  14. 一种光源系统，其特征在于，包括多色光源，所述多色光源中至少有一种颜色的光源采用如权利要求1-5任一项所述的光源调制系统、如权利要求1-13任一项所述的光源调制方法进行光源调制。
  15. 如权利要求14所述的光源系统，其特征在于，所述多色光源为红绿蓝三色光源。
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Publication number Priority date Publication date Assignee Title
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020149852A1 (en) * 2001-04-13 2002-10-17 Michael Dubinovsky Projection systems
CN105573033A (zh) * 2015-12-21 2016-05-11 中国科学院长春光学精密机械与物理研究所 提高光利用率及投影亮度的投影光学系统
CN107450258A (zh) * 2016-06-01 2017-12-08 深圳市光峰光电技术有限公司 投影系统
CN107797368A (zh) * 2016-09-05 2018-03-13 深圳市光峰光电技术有限公司 双空间光调制系统及使用该系统进行光调节的方法
CN108345160A (zh) * 2017-01-22 2018-07-31 深圳市光峰光电技术有限公司 一种投影显示系统
CN108693687A (zh) * 2017-04-06 2018-10-23 深圳市光峰光电技术有限公司 一种显示系统
CN110073290A (zh) * 2017-01-30 2019-07-30 日立乐金光科技株式会社 影像投影装置

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4747431B2 (ja) * 2001-03-28 2011-08-17 三菱電機株式会社 光源装置およびプロジェクションテレビジョン
EP1694079B1 (en) * 2001-10-01 2008-07-23 Sony Corporation Polarization selecting prism for a projection device
JP4407279B2 (ja) * 2003-12-26 2010-02-03 Ｔｄｋ株式会社 空間光変調器及び空間光変調方法
JP4556470B2 (ja) * 2004-03-30 2010-10-06 セイコーエプソン株式会社 光学表示装置
JP2013125168A (ja) * 2011-12-15 2013-06-24 Konica Minolta Advanced Layers Inc 光学ユニット及びプロジェクタ
JP6424899B2 (ja) * 2014-12-18 2018-11-21 コニカミノルタ株式会社 光学ユニット及びそれを備えたプロジェクター

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020149852A1 (en) * 2001-04-13 2002-10-17 Michael Dubinovsky Projection systems
CN105573033A (zh) * 2015-12-21 2016-05-11 中国科学院长春光学精密机械与物理研究所 提高光利用率及投影亮度的投影光学系统
CN107450258A (zh) * 2016-06-01 2017-12-08 深圳市光峰光电技术有限公司 投影系统
CN107797368A (zh) * 2016-09-05 2018-03-13 深圳市光峰光电技术有限公司 双空间光调制系统及使用该系统进行光调节的方法
CN108345160A (zh) * 2017-01-22 2018-07-31 深圳市光峰光电技术有限公司 一种投影显示系统
CN110073290A (zh) * 2017-01-30 2019-07-30 日立乐金光科技株式会社 影像投影装置
CN108693687A (zh) * 2017-04-06 2018-10-23 深圳市光峰光电技术有限公司 一种显示系统

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