Device, system, and method for controlling light source and lowest brightness region of optical modulator

Abstract

To control a light source and a lowest brightness region of an optical modulator so as not to change a color of a black pixel of a projector.SOLUTION: In a controller of a projector, a head room of a maximum luminance of a predetermined frame is determined for a predetermined image frame and a predetermined color, the head room expresses a different between a peak luminance of a peak throughput of a modulator and each maximum luminance related to the maximum luminance pixel, the light source luminance is reduced so as to be corresponded to the peak light source luminance to be reduced by the head room, the maximum luminance region of the modulator is controlled to the peak throughput. On the basis of the light source luminance to be reduced, the controller controls the lowest brightness region of the modulator to each low luminance throughput for maintaining a predetermined minimum luminance to be output by the lowest brightness region of the modulator over a whole frame to an almost constant.SELECTED DRAWING: Figure 2

Description

Background Art

[0001] Power consumption and heat generation in projectors, especially cinema projectors, are technical issues, and can potentially be mitigated by using various techniques, such as dimming the light source of an image frame that includes maximum brightness pixels having a brightness lower than the potentially peak brightness. However, such solutions may result in minimum brightness and / or black pixels where the color changes as the light source brightness changes.

Brief Description of the Drawings

[0002] To better understand the various examples described herein and to more clearly show how they may be implemented, reference is made below, by way of example, to the accompanying drawings.

[0003]

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DETAILED DESCRIPTION OF THE INVENTION

[0004] Power consumption and heat generation in a projector, particularly a high-power / high-brightness cinema projector, are technical problems and can potentially be alleviated by using various techniques such as dimming the light source of an image frame that includes maximum brightness pixels at a brightness lower than the peak achievable brightness. However, such techniques may result in a change in the color of the minimum brightness and / or black pixels. Accordingly, the present specification provides an improved technical method, apparatus, and system for controlling the minimum brightness region of a light source and a light modulator.

[0005] In particular, a projector is provided for controlling the minimum brightness region of a light source and a light modulator. The projector includes a light modulator and a controller communicatively coupled thereto, an image source that provides and receives an image frame for driving the light modulator, and at least one light source configured to irradiate the light modulator according to one or more colors. In some examples, one or more of the image source and the at least one light source may be external to the projector, while in other examples, one or more of the image source and the at least one light source may be incorporated into the projector. The projector also generally includes projection optics for projecting the light of at least one light source modulated by the light modulator onto a projection image corresponding to the image frame, for example, an object and / or a screen.

[0006] The controller generally determines the headroom of the highest luminance pixel of a predetermined image frame for a predetermined image frame and a predetermined color among one or more colors. The headroom represents the difference between the peak luminance related to the peak throughput of the light modulator and the respective highest luminance related to the highest luminance pixel, controls the light source luminance of at least one light source to a reduced light source luminance corresponding to the peak light source luminance reduced by the headroom, and controls the highest luminance region of the light modulator corresponding to the highest luminance pixel of the predetermined image frame to the peak throughput.

[0007] In a specific example, when the highest luminance pixel in a predetermined color of a predetermined image frame is 90% of the peak luminance, the headroom may be 10% (for example, the value obtained by subtracting 90% from 100%). When the light source of the predetermined color has a luminance of 100%, the light modulator may be controlled to a peak throughput of 90% (for example, in the case of a light modulator that functions according to other pulse width modulation (PWM) such as a digital micromirror device (DMD), a duty cycle of 90%, etc.). However, operating the light source at a luminance of 100% causes problems of power consumption and heat generation. Nevertheless, the headroom enables dimming of the light source of the predetermined color and can reduce power consumption and heat generation.

[0008] For example, continuing to use the example of 10% headroom, the light source of the predetermined color may be reduced to a luminance corresponding to the peak light source luminance reduced by 10% headroom. Accordingly, the highest luminance region of the light modulator corresponding to the highest luminance pixel of the predetermined image frame may be controlled to the peak throughput and / or the highest duty cycle. Therefore, when the predetermined image frame is projected, if the light source of the predetermined color is dimmed to 90% of the peak luminance and the highest luminance region of the light modulator is controlled to the peak (for example, 100%) throughput (for example, duty cycle), the highest luminance region of the corresponding projected image will be 90% luminance. Such processing is sometimes called dynamic dimming. When the light source luminance is reduced, power consumption and heat generation at the light source are also reduced.

[0009] However, dimming such light sources affects other areas of a projected predetermined image frame. In particular, the lowest luminance pixels of a predetermined image frame, such as black pixels, also have their luminance reduced, and thus, when the light source luminance changes between image frames, due to various headroom between image frames, the projected lowest luminance and / or black pixels appear to change in luminance from image frame to image frame. Further, if such dynamic dimming is different for each of the red, green, and blue light sources, the projected lowest luminance and / or black pixels not only appear to change in luminance from image frame to image frame, but may also appear to change in color.

[0010] Accordingly, the controller is also generally configured to control the lowest luminance and / or black regions of the light modulator to respective low luminance outputs corresponding to the lowest luminance and / or black pixels of a predetermined image frame, based on the reduced light source luminance (e.g., from 100% to 90%), to maintain substantially constant a predetermined lowest luminance output by the lowest luminance region of the light modulator across the image frame.

[0011] In other words, continuing to use the example of 10% headroom, the controller can control the output (e.g., and / or duty cycle) of the lowest luminance and / or black regions of the light modulator to a value that maintains the same luminance across the entire lowest luminance and / or black regions from image frame to image frame by reducing a light source of a predetermined color by 10% (etc.). Such control generally keeps the lowest luminance and / or black regions of the light modulator constant across a plurality of image frames, so that the projected black pixels do not change color.

[0012] For example, for a constant given at low luminance, when the light source luminance is at a reduced light source luminance, it may include adding to the residual luminance of the light modulator in the off state each luminance determined to bring the lowest luminance region closer to the constant given at low luminance. Thus, continuing to use the example of 10% headroom, when the light source luminance is reduced by 10% (etc.), the residual luminance of the light modulator in the off state is also generally reduced (e.g., by 10%).

[0013] Therefore, in order to maintain a substantially constant low luminance (e.g., projected by a projector), the lowest luminance of the light modulator and / or the low luminance throughput (e.g., duty cycle) of the black region is generally controlled to a predetermined value that increases the projected lowest luminance and / or the luminance of the black pixels to a predetermined value. For example, when the residual luminance of the light modulator in the off state is generally reduced by 10%, the lowest luminance of the light modulator and / or the low luminance throughput (e.g., duty cycle) of the black region, etc., can be increased by a predetermined amount to return the projected luminance of the lowest luminance and / or the black pixels to a predetermined value. Such adjustment is further performed between image frames in order to maintain a substantially constant predetermined low luminance over the entirety of a plurality of image frames.

[0014] It is further understood that the dimming of the light source affects the luminance of the intermediate luminance pixels in a given image frame. Therefore, it is further understood that the controller controls the respective throughput of the intermediate luminance pixels in a given image frame as a function of the respective luminance associated with the intermediate luminance pixels to the respective throughput between the low luminance throughput and the peak throughput. Such a function may be a linear function, but may be any suitable type of function.

[0015] One aspect of the present specification includes a light modulator and a controller communicably coupled thereto, an image source configured to provide and receive one or more image frames to drive the light modulator, and at least one light source arranged to irradiate the light modulator according to one or more colors. A method for implementing a projector, the method comprising: determining, via the controller, a headroom of a highest luminance pixel of a predetermined image frame among the plurality of image frames and a predetermined color among one or more colors, the headroom representing a difference between a peak luminance related to a peak throughput of the light modulator and each highest luminance related to the highest luminance pixel; controlling, via the controller, a light source luminance of the at least one light source to a reduced light source luminance corresponding to a peak light source luminance reduced by the headroom; controlling, via the controller, a highest luminance region of the light modulator corresponding to the highest luminance pixel of the predetermined image frame to have the peak throughput; and controlling, via the controller, a lowest luminance region of the light modulator corresponding to a lowest luminance pixel of the predetermined image frame to a respective low luminance throughput that maintains a substantially constant predetermined low luminance output by the lowest luminance region of the light modulator across the plurality of image frames, based on the reduced light source luminance. A method for implementing a projector is provided.

[0016] Another aspect of the present specification is a projector, comprising a light modulator and a controller communicatively coupled thereto, an image source configured to provide and receive one or more image frames for driving the light modulator, and at least one light source arranged to irradiate the light modulator according to one or more colors. The controller determines a headroom of a highest luminance pixel of a predetermined image frame among the plurality of image frames and a predetermined color among the one or more colors, the headroom representing a difference between a peak luminance related to a peak throughput of the light modulator and each highest luminance related to the highest luminance pixel, controls a light source luminance of at least one light source to a reduced light source luminance corresponding to a reduced peak light source luminance reduced by the headroom, controls a highest luminance region of the light modulator corresponding to the highest luminance pixel of the predetermined image frame to have a peak throughput, and controls a lowest luminance region of the light modulator corresponding to a lowest luminance pixel of the predetermined image frame to a respective low luminance throughput that maintains a substantially constant predetermined low luminance output by the lowest luminance region of the light modulator over the entirety of the plurality of image frames, based on the reduced light source luminance.

[0017] FIG. 1 shows a system 100 comprising a projector 102 including a controller 104, a light modulator 106, and a memory 108 storing one or more applications 110, an image source 112, and at least one light source 114. The controller 104 is understood to be communicatively coupled to the image source 112 and the at least one light source 114. The various components of the system 100 communicate via any suitable combination of wired and / or wireless communication links, and throughout FIG. 1 and this specification, the communication links between the components of the system 100 are shown as double-ended arrows between the respective components.

[0018] As shown, the image source 112 may be communicatively coupled to an optional rendering device 116, and (as shown) the image source 112 may include a content player and / or a content generator. As shown, the rendering device 116 and the image source 112 may be coupled to a single device 118 (depicted by a dashed line to represent such an optional coupling of the rendering device 116 and the image source 112). However, in other embodiments, the rendering device 116 and the image source 112 may be separate devices. Although not shown, the rendering device 116 and / or the device 118 may be communicatively coupled to an alignment system configured to generate pose data including at least data defining a geometric relationship between, for example, the projector 102 and an object projected by the projector 102 (including the screen 120 and / or other suitable objects on which projection mapping is performed). Generally, such pose data may be composed of the position of the projector 102 (e.g., “x, y, z” coordinates relative to the object and / or the screen 120) and the orientation of the projector 102 (e.g., “yaw,” “pitch,” and “roll” relative to the object and / or the screen 120). In some examples, although not shown, the system 100 may further include a camera to assist in generating the pose data. For simplicity of explanation hereinafter, reference is made to projecting onto the screen 120, but the projection may be performed on any suitable object.

[0019] When present, the rendering device 116 can generate the rendered image data 122, for example, by rendering existing image data (not shown) for projection by the projector 102. The image data 122 may generally be composed of a two-dimensional image. The image source 112 can combine the pose data received from the alignment system (and any object data that can define the shape of the object and / or the screen 120) with the image data 122 to generate the image frame 124. This image frame 124 includes the image data 122 that has been changed according to the viewpoint for projection onto the object by the projector 102. Alternatively, the image source 112 may receive the image frame 124 and "play back" the image frame 124. Therefore, the image source 112 is understood to be one or more of generating and receiving the image frame 124 and providing the image frame 124 to the controller 104 of the projector 102.

[0020] When the rendering device 116 and the image source 112 are separate, the rendering device 116 communicates the image data 122 to the image source 112 that processes and / or "plays back" the image data 122 by generating an image frame 124 suitable for processing and projection by the projector 102.

[0021] The image data 122 may include, but is not limited to, AVI files, a series of JPG files, PNG files, etc. The image frame 124 includes, but is not limited to, High-Definition Multimedia Interface (HDMI (registered trademark)) data, Digital Visual Interface (DVI) data, DisplayPort (DP) data, Video over Internet Protocol (IP) data, Video Graphics Array (VGA) data, and / or video transport data, etc.

[0022] When the rendering device 116 and the image source 112 are coupled in the device 118, the device 118 may render the image frame 124 (e.g., video data) in real time without generating the image data 122. In any case, the image frame 124 is communicated by the image source 112 to the projector 102, where the image frame 124 is used to control the projector 102, for example, to project a frame-based image onto a two-dimensional or three-dimensional object such as the screen 120. The image frame 124 may include an image for projection onto the screen 120 and may include, for example, the image data 122 modified according to the perspective of the projector 102 with respect to the screen 120 determined using pose data and / or object data. However, the image frame 124 may further include pose data, external properties of the projector 102, settings of the projector 102, and the like.

[0023] The rendering device 116 generally includes an image generator and / or renderer, such as a computing device, a server, etc., configured to generate and / or render an image as the image data 122. Such image data 122 may include, but is not limited to, still images, videos, etc. Further, although not shown, the rendering device 116 may communicate with and / or include a memory that stores data for generating and / or rendering the image data 122. Alternatively, the rendering device 116 may generate the image data 122 using an algorithm or the like for generating an image.

[0024] The image source 112 may be composed of a player configured to "play" and / or render the image data 122. When the image data 122 includes video data, the image source 112 is configured to play and / or render the video data by outputting the image frame 124 for projection by the projector 102. Thus, the image source 112 can include, but is not limited to, a video player, a video processing device, a computing device, a server, etc. However, as described above, when the rendering device 116 and the image source 112 are coupled as the device 118, the rendering of the image data 122 may be omitted, and the device 118 renders the image frame 124 without generating the image data 122.

[0025] The projector 102 includes a projector configured to project the image frame 124, and includes, but is not limited to, a digital projector, a cinema projector, a liquid crystal (LCD)-based projector, a liquid crystal on silicon (LCOS)-based projector, a digital micromirror device (DMD)-based projector, etc. Thus, the light modulator 106 may be composed of any suitable corresponding type of light modulator, such as an LCS-based light modulator, an LCOS light modulator, a DMD light modulator, etc. In the example provided in this specification, for simplicity, the light modulator 106 including a DMD is referred to.

[0026] Furthermore, although only one projector 102 is shown in the figure, the system 100 can include a plurality of projectors, and each projector is configured to project respective projection data including, for example, a portion of a larger tiled image to be projected.

[0027] Regardless of the technology used in projector 102, it is assumed that projector 102, and / or other projectors described herein, include an image modulator that includes a plurality of individual pixel modulators. For example, if the projector is configured as a DMD projector, the image modulator is composed of a plurality of digital micromirrors each having one micromirror for each pixel of the image to be projected.

[0028] At least one light source 114 (referred to interchangeably herein as light source 114 for simplicity) may comprise any suitable light source configured to irradiate light modulator 106 with light 126. For example, as shown, at least one light source 114 may be external to projector 102, and projector 102 may include an aperture for capturing light 126, any suitable optical system for providing light 126 disposed between light source 114 and projector 102, or both. However, light source 114 may alternatively be incorporated into projector 102.

[0029] In particular, light source 114 may be composed of a laser light source and / or other light sources whose brightness is controlled by controller 104. In some examples, light source 114 may be composed of a red light source, a green light source, and a blue light source (e.g., a red laser, a green laser, and a blue laser), which may be continuously controlled to irradiate light modulator 106 in the order of red light, green light, and blue light, and controller 104 may accordingly control light modulator 106 to generate a red image frame, a green image frame, and a blue image frame in the projection-modulated light 128, which is projected onto screen 120 (etc.) via the projection optical system 130 of projector 102 (e.g., projector 102 further includes projection optical system 130), and such projection is represented by the dashed line between projection optical system 130 and screen 120.

[0030] Alternatively, the light 126 may be white, and the projector 102 may be configured with an appropriate optical system for separating the light 126 into red, green, and blue. Alternatively, although only one light modulator 106 is shown, the projector 102 may be configured with three dedicated light modulators 106 for modulating red light, green light, and blue light, respectively, and the controller 104 may control the three light modulators 106 as described herein.

[0031] Although each of the rendering device 116, the image source 112 (and / or device 118), and the light source 114 is shown as a component different from the projector 102, in other embodiments, one or more respective portions of the rendering device 116, the image source 112 (and / or device 118), and the light source 114 may be incorporated into the projector 102, and / or the entire system 100 may be provided as the projector 102.

[0032] Controller 104 can include one or more central processing units (CPUs) and / or one or more graphics processing units (GPUs) and / or one or more other processing devices, i.e., it can include a processor and / or multiple processors, but is not limited thereto. In any case, controller 104 is composed of hardware elements and / or a hardware processor. In some embodiments, controller 104 may include an application-specific integrated circuit (ASIC) and / or a field-programmable gate array (FPGA) specifically configured to control the lowest luminance regions of the light source and the optical modulator (e.g., optical modulator 106). In fact, controller 104 is preferably not just a controller, but a controller specifically configured to perform specific functions for controlling the lowest luminance regions of the light source and the optical modulator (e.g., optical modulator 106). For example, controller 104 may specifically include a computer-executable engine configured to perform functions for controlling the lowest luminance regions of the light source and the optical modulator.

[0033] Memory 108 may include a non-volatile storage device (e.g., erasable electronically programmable read-only memory (“EEPROM”), flash memory), and a volatile storage device (e.g., random access memory (“RAM”)). As described herein, the programming instructions for implementing the functional teachings of projector 102 are typically permanently held in memory 108 and are used by controller 104 that appropriately utilizes volatile storage during the execution of such programming instructions. Those skilled in the art will recognize that memory 108 is an example of a computer-readable medium that can store programming instructions executable on controller 104. Also, memory 108 is an example of a memory unit and / or a memory module and / or a non-volatile memory.

[0034] In particular, when processed by the controller 104, the memory 108 stores one or more applications 110 (hereinafter referred to as application 110 for simplicity) that enable the controller 104 and / or the projector 102 to execute the blocks of the method described herein with respect to FIG. 2.

[0035] Although not shown, the projector 102 may further include any suitable wired or wireless communication interface that enables the controller 104 to communicate with other components of the external system 100 of the projector 102. Such an interface can communicate, as required, wired and / or wirelessly, such as via cables, WiFi (registered trademark) communication links, Bluetooth (registered trademark) communication links, personal area networks, local area networks, etc., but is not limited thereto.

[0036] Here, FIG. 2 shows a flowchart of a method 200 for controlling the minimum luminance regions of a light source and a light modulator according to a non-limiting example. The operations of method 200 may correspond to machine-readable instructions executed by the projector 102, specifically the controller 104 of the projector 102. In the illustrated example, the instructions represented by the blocks of FIG. 2 are stored in the memory 108, for example, as application 110. The method 200 of FIG. 2 is an example of a way in which the controller 104 and / or the projector 102 and / or the system 100 can be configured. Further, the following description of the method 200 of FIG. 2 leads to a further understanding of the system 100 and its various components.

[0037] The method 200 of FIG. 2 need not be executed in the exact order shown, and similarly, various blocks may be executed in parallel rather than in sequence. Accordingly, the elements of method 200 are referred to herein as "blocks" rather than "steps".

[0038] Method 200 of FIG. 2 can also be implemented in a variant of system 100. However, in the following description, it is understood that projector 102 includes a light modulator 106, an image source 112 configured to provide and receive one or more image frames 124 (which are then provided to controller 104 and used to drive light modulator 106), and at least one light source 114 configured to irradiate light modulator 106 according to one or more colors, and a controller 104 communicatively coupled thereto.

[0039] In block 202, controller 104 and / or projector 102 determine the headroom of the highest luminance pixel of a predetermined image frame 124 within image frame 124 and a predetermined color among one or more colors generated by light source 114, where the headroom represents the difference between the peak luminance associated with the peak throughput of light modulator 106 and the actual highest luminance associated with the highest luminance pixel. It is further understood that the remaining blocks of method 200 are performed with respect to the predetermined image frame 124 and the predetermined color of block 202.

[0040] As used herein, the term "peak throughput" is understood to include the state in which light modulator 106 is controlled (e.g., by controller 104) such that its pixel provides the maximum amount of light from light source 114 to screen 120. Similarly, a pixel of light modulator 106 controlled by peak throughput may include being controlled such that the pixel provides the maximum amount of light from light source 114 to screen 120. Similarly, when a pixel of light modulator 106 is controlled to minimum throughput, the pixel may be in a state where it is controlled such that the amount of light the pixel supplies from light source 114 to screen 120 is minimized. The throughput of a pixel may be between the minimum throughput and the peak throughput.

[0041] It is understood that each maximum brightness associated with the maximum brightness pixel is generally lower than the peak brightness (for example, otherwise the headroom would be 0%).

[0042] In block 204, the controller 104 and / or the projector 102 control the light source brightness of at least one light source 114 to a reduced light source brightness corresponding to the peak light source brightness reduced by the headroom.

[0043] In block 206, the controller 104 and / or the projector 102 control the maximum brightness region of the light modulator 106 corresponding to the maximum brightness pixel of a predetermined image frame 124 to the peak throughput.

[0044] In block 208, the controller 104 and / or the projector 102 control the minimum brightness region of the light modulator 106 corresponding to the minimum brightness pixel of a predetermined image frame 124 to a low brightness throughput that maintains a substantially constant predetermined low brightness output by the minimum brightness region of the light modulator 106 across the entire image frame 124, based on the reduced light source brightness.

[0045] It is understood that the minimum brightness pixel of a predetermined image frame 124 may correspond to a black pixel.

[0046] Furthermore, method 200 is performed, for example, in parallel for a plurality of predetermined image frames 124 and all of one or more colors generated by the light source 114, and for each minimum brightness pixel of one or more colors, a substantially constant predetermined low brightness is maintained for each of the projected pixels across all image frames 124, such that the brightness and color of each of the projected minimum brightness pixels do not change across the image frames 124.

[0047] Furthermore, method 200 may be executed dynamically, for example when image frame 124 is received, and / or method 200 may be executed prior to projection of image frame 124 using the respective reduced light source luminance determined in blocks 202, 204 for the image frame 124 stored in memory 108 (e.g., as a module of application 110) in relation to the respective low luminance throughput determined in block 208, which maintains a substantially constant predetermined low luminance output by the lowest luminance region of the light modulator across the entire image frame 124.

[0048] It is further understood that for a given color, the lowest luminance pixel is the same lowest luminance across the entire image frame 124. Thus, for example, while one image frame 124 has a lowest luminance pixel of "0" (e.g., on a scale of 0 to 100 where "0" is pure black and "100" is pure white), and a second image frame 124 has a lowest luminance pixel of "1" (e.g., grayscale), the lowest luminance pixel of the second image frame 124 is treated as an intermediate luminance pixel. However, if all image frames 124 do not have a lowest luminance pixel of "0", the lowest luminance becomes "1", and such luminance pixels of "1" are treated as lowest luminance pixels.

[0049] However, it is understood that method 200 may be implemented for intermediate luminance pixels, and controller 104 controls the intermediate luminance region of the light modulator corresponding to the intermediate luminance pixels in a given image frame having a given intermediate luminance to an intermediate luminance throughput corresponding to each region, thereby maintaining a substantially constant predetermined intermediate luminance output from the intermediate luminance region of the light modulator across the entirety of a plurality of image frames.

[0050] In other words, the projected lowest luminance pixel of luminance "1" is controlled to the same projected luminance across the entire image frame 124.

[0051] Method 200 can include additional features.

[0052] For example, the substantially constant predetermined low luminance in block 208 can include the residual luminance of the light modulator 106 in the off state plus the respective luminance determined to reach the lowest luminance region to the substantially constant predetermined low luminance when the light source luminance is the reduced light source luminance.

[0053] For example, turning to FIG. 3 next, a color vector 300 is shown which is an example of a projected pixel in the tristimulus space (Φ 3 ). Vector 300 may represent a projected lowest luminance pixel, or a projected highest luminance pixel of a predetermined image frame 124, or a projected intermediate luminance pixel (e.g., having an intermediate luminance between the projected lowest luminance pixel and the projected highest luminance pixel).

[0054] Vector 300 is represented as follows:

[0055]

Number

[0056] TIFF2025108355000003.tif15162

[0057] Also, in Equation (1), "thrpt" is the throughput of the pixels of the optical modulator 106 that generates the vector 300, and represents a value such as a portion of the time when the pixels of the optical modulator 106 are "on" in a predetermined image frame 124, and may be a value between 0 and 1 (or between 0% and 100% and / or between 0 and 100, and / or other appropriate scales). Therefore, when the value of "thrpt" is "0", the pixels of the optical modulator 106 are "off" for the entire predetermined image frame 124, and may generate black projected pixels and / or projected pixels with the lowest luminance. Similarly, when the value of "thrpt" is "1", the pixels of the optical modulator 106 are "on" for the entire predetermined image frame 124, and may generate white projected pixels with the highest luminance and / or colored projected pixels. When the value of "thrpt" is between "0" and "1", the pixels of the optical modulator 106 are "on" for a portion of the predetermined image frame 124, and may generate gray projected pixels with intermediate luminance and / or colored projected pixels. In the case of a DMD and / or other types of optical modulators 106 that operate according to PWM (e.g., DMD), the throughput may instead be referred to as a duty cycle. However, for other types of optical modulators 106 that do not operate according to PWM (e.g., LCD-based optical modulators and / or LCOS optical modulators, etc.), the term throughput may be used (e.g., LCD-based optical modulators and / or LCOS optical modulators do not operate according to a duty cycle).

[0058] Also, in Equation (1), "Bright" is the luminance of the light 126 of the color of the light source 114 that irradiates the pixels of the optical modulator 106, and may be a value between 0% and 100% (e.g., 0% represents that the light source 114 is in an off state, and 100% represents that the light source is at a peak or maximum luminance), but the value of "Bright" may be between 0 and 1, or between 0 and 100, or other appropriate scales.

[0059] Therefore, the term "thrpt*Bright" is understood to represent the luminance of the projected pixel represented by vector 300, which is due to the interaction between light 126 and the pixels of the light modulator 106.

[0060] TIFF2025108355000004.tif68163

[0061] TIFF2025108355000005.tif15163

[0062] However, since the luminance "Bright" of light 126 may change (e.g., at block 204) due to changes in headroom, the residual luminance Ro may change from image frame 124 to image frame 124.

[0063] TIFF2025108355000006.tif38163

[0064] TIFF2025108355000007.tif42163

[0065] TIFF2025108355000008.tif37163

[0066] In other words, method 200 can further comprise controller 104 and / or projector 102 as the light source luminance decreases from image frame 124 to image frame 124 due to changes in headroom: each low luminance throughput is varied to maintain a substantially constant predetermined minimum luminance in the lowest luminance region of light modulator 106 corresponding to the lowest luminance pixel of a given image frame 124. In this way, the luminance and color of the projected lowest luminance pixels are maintained across image frame 124.

[0067] A similar process may be performed on the intermediate luminance pixels such that the projected intermediate luminance pixels corresponding to the intermediate luminance pixels having the same luminance across image frame 124 do not change in luminance or color across image frame 124.

[0068] However, the control of the intermediate luminance pixels may be performed using a function. For example, method 200 further includes a controller 104 and / or a projector 102 corresponding to each intermediate luminance between the lowest luminance associated with the lowest luminance pixels and the highest luminance associated with the highest luminance pixels for the intermediate luminance pixels of a predetermined image frame 124, and based on the value of the reduced light source luminance of at least one light source 114, controls the respective throughput of the intermediate luminance region of the light modulator 106 corresponding to the intermediate luminance pixels of the predetermined image frame 124 to a respective intermediate luminance throughput that substantially maintains a predetermined luminance output by the intermediate luminance region of the light modulator 106 across the entire image frame 124.

[0069] Method 200 can further include a controller 104 and / or a projector 102, and controls the respective throughput of the intermediate luminance pixels of a predetermined image frame 124 to respective intermediate luminance throughputs between the low luminance throughput and the peak throughput as a function of the respective luminance associated with the intermediate luminance pixels.

[0070] For example, such a function may be linear or other suitable function.

[0071] When the function is linear, method 200 can further include a controller 104 and / or a projector 102, and linearly controls the respective throughput of the intermediate luminance pixels of a predetermined image frame 124 to respective intermediate luminance throughputs between the low luminance throughput and the peak throughput as a function of the respective luminance associated with the intermediate luminance pixels.

[0072] TIFF2025108355000009.tif82163

[0073] TIFF2025108355000010.tif32163

[0074] Further, in some embodiments, at least one light source 114 comprises a red laser, a green laser, and a blue laser, and method 200 may be performed in parallel for the red laser, the green laser, and the blue laser. For example, each headroom may be determined for each of the red laser, the green laser, and the blue laser from, for example, a red image frame component, a green image frame component, and a blue image frame component of a predetermined image frame 124 of block 202 of method 200. Further, in these examples, each of the red laser, the green laser, and the blue laser is controlled according to each headroom for each of the red laser, the green laser, and the blue laser (e.g., in block 204 of method 200). Further, in these examples, for each of red, green, and blue, each throughput for each respective highest luminance pixel and each respective lowest luminance pixel is controlled according to each headroom for each of the red laser, the green laser, and the blue laser (e.g., in blocks 206 and 208 of method 200).

[0075] Next, turning to FIGS. 4, 5, and 6 in which a portion of system 100 is operating in a different mode, at least FIGS. 5 and 6 illustrate an example of method 200. In particular, FIG. 4 shows a portion of system 100 operating without performing method 200 (e.g., without dynamic dimming), and FIGS. 5 and 6 show a portion of system 100 operating while performing method 200 (e.g., using dynamic dimming). Not all components of system 100 are shown in FIGS. 4, 5, and 6, but it is understood that such components exist.

[0076] Further, FIGS. 4 and 5 are shown with the same image frame 124-1 of a test pattern having four bands of pixels corresponding to pixels of 90% maximum luminance, 60% luminance, 30% luminance, and 0% luminance.

[0077] FIG. 6 shows another image frame 124-2 of another test pattern having pixels in four bands corresponding to a maximum luminance pixel of 60% luminance, 30% luminance, 10% luminance, and 0% luminance.

[0078] In all of FIGS. 4, 5, and 6, it is understood that the maximum luminance pixels of each image frame 124 are less than 100% peak luminance, and the minimum luminance pixels of each image frame 124 are black pixels.

[0079] First, referring to FIG. 4, in the illustrated form, the system 100 may operate without dynamic dimming. The regions of the light modulator 106 corresponding to the four bands of the image frame 124-1 are controlled to respective throughputs corresponding to the luminance of the four bands (e.g., 0.9, 0.6, 0.3, and 0), and the light source 114 is controlled to 100% maximum luminance.

[0080] Accordingly, the modulated light 128 projected onto the screen 120 generates a projected image 402 including the four bands of the image frame 124-1.

[0081] However, further referring to Equation (1), the residual luminance Ro1 of the region of the light modulator 106 where the throughput is controlled to 0 contributes to the luminance of the black band of the projected image 402, as indicated by, for example, the text “0 throughput (+Ro)” in the light modulator 106 and the text “0%+Ro)” in the projected image 401. Such residual luminance Ro1 also contributes to the other bands of the projected image 402, but the higher the luminance, the less noticeable the residual luminance Ro1. For simplicity, the residual luminance Ro is omitted in the regions of the light modulator 106 corresponding to pixels other than the lowest luminance of the image frame 124-1.

[0082] Next, turning to FIG. 5. In the illustrated mode, the system 100 can operate with dynamic dimming. Thus, FIG. 5 is similar to FIG. 4, but the controller 104 implements the method 200.

[0083] In these examples, since the peak luminance region of image frame 124-1 (e.g., the same image frame as in FIG. 4) is 90%, there is 10% headroom (e.g., determined at block 202 of method 200). Thus, the light source 114 is controlled to a reduced luminance of 90% (e.g., as determined at block 204 of method 200), and the regions of the light modulator 106 corresponding to the four bands of image frame 124-1 are controlled to respective throughputs that generate a projection image 502 that is at least similar to the projection image 402 in the corresponding 90%, 60%, and 30% regions (e.g., as determined at block 206 of method 200).

[0084] For example, the throughput of the region of the light modulator 106 corresponding to the highest luminance pixel “90%” of a given image frame 124-1 is controlled to “1”, the throughput of the region of the light modulator 106 corresponding to the next highest luminance pixel “60%” of the given image frame 124-1 is controlled to “0.67”, and the throughput of the region of the light modulator 106 corresponding to the next highest luminance pixel “30%” of the given image frame 124-1 is controlled to “0.33”.

[0085] Specifically, ignoring afterglow and using Equation (1), for the highest luminance pixel “90%” of a given image frame 124-1, in the example of FIG. 4, the term “thrpt*Bright” is “0.9*100%” (e.g., thrpt = 0.9 and Bright = 100%) or 90%, and similarly, in the example of FIG. 5, the term “thrpt*Bright” is “1*90%” (e.g., thrpt = 1 and Bright = 90%) or 90%, as will be understood.

[0086] Similarly, for the next highest luminance pixel “60%” of a given image frame 124-1, in the example of FIG. 4, the term “thrpt*Bright” is “0.6*100%” (e.g., thrpt = 0.6 and Bright = 100%) or 60%, and similarly, in the example of FIG. 5, the term “thrpt*Bright” is “0.67*90%” (e.g., thrpt = 0.67 and Bright = 90%) or 60%.

[0087] Similarly, for the second highest luminance pixel “30%” following a predetermined image frame 124-1, in the example of FIG. 4, the term “thrpt*Bright” is “0.3*100%” (e.g., thrpt = 0.3 and Bright = 100%) or 30%, and similarly, in the example of FIG. 5, the term “thrpt*Bright” is “0.33*90%” (e.g., thrpt = 0.33 and Bright = 90%) or 30%.

[0088] Therefore, in the example of FIG. 5, compared with the example of FIG. 4, since the throughput in the optical modulator 106 increases, the luminance of the light source 114 decreases, and as a result, the power consumption decreases, so similar and / or the same results are achieved, and similar projected images 402, 502 may be obtained.

[0089] However, regarding the lowest luminance region of a predetermined image frame 124-1, each region of the optical modulator 106 is controlled to a throughput of 0.010 (as determined, for example, in block 208 of method 200), and since such throughput is low compared to the throughput of other regions, it is understood that the afterglow significantly contributes to the luminance of the corresponding projected image 502. It is understood that a throughput of 0.010 is selected to reach a substantially constant predetermined low luminance of the projected image 502:

[0090]

Number

[0091] TIFF2025108355000012.tif50163

[0092] TIFF2025108355000013.tif44163

[0093]

Number

[0094] Furthermore, R black is understood to be greater than (0% + Ro) and / or brighter than the band corresponding to the projection image 402.

[0095] Referring now to FIG. 6, the controller 104 continues to implement the method 200 to generate a projection image 602 with pixels of 60%, 30%, 10%, and 0% luminance for another image frame 124-2. Thus, the headroom is 40% (e.g., 100% - 60%), and the controller 104 can control the light source 114 to 60% luminance (e.g., 100% - 40%).

[0096] Thus, the regions of the light modulator 106 corresponding to the four bands of the image frame 124-2 are controlled to their respective throughputs for generating the projection image 602 (e.g., determined in block 206 of method 200).

[0097] For example, the throughput of the region of the light modulator 106 corresponding to the highest luminance pixel “60%” of a given image frame 124 is controlled to “1”, the throughput of the region of the light modulator 106 corresponding to the next highest luminance pixel “30%” of the given image frame 124 is controlled to “0.5”, and the throughput of the region of the light modulator 106 corresponding to the next highest luminance pixel “10%” of the given image frame 124 is controlled to “0.16”.

[0098] Specifically, ignoring the afterglow luminance and using Equation (1), for the highest luminance pixel “60%” of a given image frame 124-2, in the example of FIG. 6, the term “thrpt*Bright” is “1*60%” (e.g., thrpt = 1 and Bright = 60%) or 60%, which is understood to be the same for a throughput of 0.6 and a luminance of 100% (e.g., when the system 100 operates without dynamic dimming).

[0099] Comparing this example with the example of FIG. 5, for the area of the image modulator 106 corresponding to the 60% luminance area of the image frame 124-1, since the luminance of the light source 114 decreases, the throughput increases from 0.67 to 1. Therefore, the corresponding "60%" bands in the projected images 502, 602 have the same and / or similar luminance because each has 60% luminance. These calculations are simplified, and it is again understood that matrix calculations may be performed considering other factors, especially changes in residual luminance due to the decrease in the luminance of the light 126 from FIG. 5 to FIG. 6.

[0100] Similarly, in the example of FIG. 6, for the "30%" next-highest luminance pixels of a given image frame 124, the term "thrpt*Bright" is "0.5*60%" (e.g., thrpt = 0.5 and Bright = 60%) or 30%, which is the same as the case when the throughput is 0.3 and the luminance is 100% (e.g., when the system 100 operates without dynamic dimming).

[0101] Comparing this example with the example of FIG. 5, for the area of the image modulator 106 corresponding to the 30% luminance area of the image frame 124-1, since the luminance of the light source 114 decreases, the throughput increases from 0.33 to 0.5. Therefore, the corresponding "30%" bands in the projected images 502, 602 have the same and / or similar luminance because each has 30% luminance. These calculations are simplified, and it is again understood that matrix calculations may be performed considering other factors, such as changes in residual luminance due to the decrease in the luminance of the light 126 from FIG. 5 to FIG. 6.

[0102] Similarly, in the example of FIG. 6, for the next-highest luminance pixel "10%" of a given image frame 124, the term "thrpt*Bright" is "0.16*60%" (e.g., thrpt = 0.16 and Bright = 60%) or 10%, which is the same as the case with a throughput of 0.1 and a luminance of 100% (e.g., when the system 100 operates without dynamic dimming).

[0103] However, for the lowest luminance region of a given image frame 124-2, each region of the light modulator 106 is controlled to a throughput of 0.014 (as determined, for example, in block 208 of method 200), and since such throughput is low compared to the throughput of other regions, it is understood that the afterglow significantly contributes to the luminance of the corresponding projected image 602. It is understood that a throughput of 0.0155 is selected to reach the luminance of the corresponding region of the projected image 602 to a substantially constant predetermined low luminance:

[0104]

Number

[0105] TIFF2025108355000016.tif64163

[0106] TIFF2025108355000017.tif32163

[0107]

Number

[0108] Therefore, the value of the term "thrpt2" is selected accordingly, and accordingly, by controlling the throughput of each region of the light modulator 106 corresponding to the lowest luminance region of the given image frame 124-2 to such a value, the luminance of the lowest luminance region of the projected image 602 is controlled to the same luminance as the lowest luminance region of the projected image 502.

[0109] For example, in equations (2) and (4), using throughputs of 0.010 and 0.0155, luminances of 90% and 60% respectively, and afterglows of 0.09 and 0.06 respectively (e.g., using Ro of 0.001, where Ro1 is Ro multiplied by a gain factor of 90% and Ro2 is Ro multiplied by a gain factor of 60%), the value of Rblack becomes the same value as 0.99.

[0110] TIFF2025108355000019.tif20163

[0111] TIFF2025108355000020.tif48163

[0112] Next, focus on FIG. 8 showing another vector 800 defined by Equation (6):

[0113]

Number

[0114] TIFF2025108355000022.tif59161

[0115] TIFF2025108355000023.tif37161

[0116] Furthermore, when the light source 114 is dimmed, it changes in the same way as the throughput change at 100% brightness of the light source 114 and at brightness less than 100% of the light source 114, and the influence on the projection brightness becomes smaller. Thus, it is further understood that more contrast levels become available at lower projection brightness. For example, if the throughput at 100% brightness of the light source 114 changes by 0.1, the projection brightness changes by 10%. On the other hand, if 0.1 of the throughput at 50% brightness of the light source 114 changes, the projection brightness changes by 5%. Therefore, more gray levels may be available during dynamic dimming and / or during the execution of method 200. In fact, the controller 104 can increase the available gray levels of the image frame 124 by dimming the light source 114. However, such an increase may occur in a part of the image frame 124 corresponding to a scene (e.g., of a video) where the dimming is constant so that the change in the gray scale does not vary across the entire scene. For example, a file corresponding to the image frame 124 is received and processed by any suitable component of the system 100 (e.g., any component of the controller 104 and / or the device 118) to determine the image frame 124 corresponding to a scene to which the method 200 may be applied to apply dynamic dimming, and accordingly, a gray scale can be appropriately added to the image frame 124 (e.g., by adjusting the image frame 124 to include more gray scales than originally included in the image frame 124).

[0117] Next, referring to FIG. 9, it shows that the percentage of the luminance of the incident light (e.g., from the light source 114) supplied by the pixels of the optical modulator 130 to the screen 104 changes as the controller 104 outputs a control signal to the optical modulator, and the control signal attempts to control the throughput of the optical modulator from 0% to 100% (and / or, as shown, between 0 and 1 if the control signal is dimensionless). As shown, in the case of 0% throughput (e.g., the pixel is controlled to pure black), the optical modulator 130 still provides a residual luminance Ro of 5% of the light from the light source 114 to the screen 120. In fact, the 5% residual luminance Ro is maintained across all throughputs from 0% to 100%, however, even in the case of 100% across the board, the luminance of the light from the light source 114, i.e., the modulation depth of the optical modulator R1 representing the modifiable light, is only 95% of the light from the light source 114 (e.g., 100% minus the 5% of the residual luminance Ro). Therefore, Ro and R1 may be constants, and in a simple model, it is understood that R1 = 100% - Ro.

[0118] Furthermore, the luminance output by the optical modulator 130 may be expressed as a scalar term (e.g., ignoring the aforementioned vector):

[0119] [Number]

[0120] In Equation (7), L is the light generated by the pixels of the optical modulator 130 (e.g., as provided to the screen 120), Ro is the residual luminance (e.g., 5% as in FIG. 9), R1 is the modulation depth (e.g., the percentage of the optical output modulated by the optical modulator 130, which may be a constant defined by 100% - Ro), C is the value of the control signal for controlling the throughput (e.g., corresponding to 0% to 100% throughput respectively and may range from 0 to 1 as in FIG. 9), and S is the percentage of the luminance of the light output from the light source 114.

[0121] As described in this specification, the light output by the pixels of the optical modulator 130 is the same under conditions "A" and "B". For example, under condition A, the control signal is C A and the percentage of the luminance of the light emitted by the light source 114 is S A and, for example, under condition A, normal operation in which the light source 114 is controlled to 100% is possible. Similarly, under condition B, the control signal is C B and the percentage of the luminance of the light output by the light source 114 is S B and, for example, condition B is a condition in which the light source 114 is dimmed. For both of these conditions, Equation (7) may be rewritten as follows (for example, for the light L A , L B respectively generated by the pixels of the optical modulator 130 under conditions A and B):

[0122]

Number

[0123]

Number

[0124] Setting Equation (8) equal to Equation (9), L A , L B is equal under conditions A and B:

[0125]

Number

[0126] C A solution:

[0127]

Number

[0128] Condition A is the luminance S of the light source 114 B is 100%, but the control signal C A is lower than 100%. In condition B, assuming that the luminance S of the light source 114 B is in a reduced state from 100% (e.g., according to block 202 of method 200), the control signal C B that maintains the same brightness (e.g., like blocks 206 and 208 of method 200, but for the highest and lowest luminance pixels) may be determined from equation (11). For example, for the highest luminance pixel, C B is set to the C that is the control signal for controlling the pixel of the light modulator 114 to the highest luminance A and may be determined using it. For the lowest luminance pixel, C B is set to the C that is the control signal for controlling the pixel of the light modulator 114 to the lowest luminance A and may be determined using it.

[0129] In fact, equation (11) indicates that the relationship between luminance, afterglow, and the control signal to the light modulator, and how such a relationship affects the throughput and / or light provided from the light modulator to the screen 120, may not be strictly linear.

[0130] As is clear here, the operations and functions of the devices described herein are so complex that they require execution on a computer system and, as a practical matter, cannot be performed in a human's head. In particular, computing devices such as those described herein require, in addition to the inherently digital nature of such operations, the management of speed, accuracy, and complexity that cannot be obtained by human mental steps and are understood to be provided (e.g., a human mind cannot directly interface with a digital projector, nor can it project light or adjust the throughput of a light modulator, etc.).

[0131] Examples of the term "configured", such as "a computing device configured to...", "a processor configured to...", "a controller configured to...", etc., may be understood to include a computer-readable storage medium storing program instructions that, when executed by a computing device and / or a processor and / or a controller, etc., cause the computing device and / or the processor and / or the controller, etc., to perform a series of operations that can include features configured to be performed by the computing device and / or the processor and / or the controller, etc. Therefore, it should be further understood that the term "configured" is not overly limited to means-plus-function or the like.

[0132] Furthermore, descriptions of one processor and / or a controller and / or a device and / or an engine, etc., configured to perform a particular function are understood to include, but are not limited to, two or more processors and / or one or more controllers and / or one or more devices and / or one or more engines, etc., performing such a function.

[0133] For the purposes of this specification, it is understood that the phrases "at least one of X, Y, and Z" and "one or more of X, Y, and Z" may be interpreted as only X, only Y, only Z, or any combination of two or more items X, Y, and Z (e.g., XYZ, XY, YZ, XZ, etc.). Similar logic may apply to two or more items when the phrases "at least one..." and "one or more..." appear arbitrarily.

[0134] Terms such as "about", "substantially", "essentially", "approximately", etc., are defined as "near", as understood by one of ordinary skill in the art, for example. In some examples, these terms are understood to be "within 10%", in other examples "within 5%", in still other examples "within 1%", and in yet other examples "within 0.5%".

[0135] Those skilled in the art will understand that the functions of the devices and / or methods and / or processes described herein may be implemented using pre-programmed hardware or firmware elements (e.g., application-specific integrated circuits (ASICs), electrically erasable programmable read-only memories (EEPROMs), etc.), or other related components. In other examples, the functions of the devices and / or methods and / or processes described herein may be achieved using a computing device that accesses a code memory (not shown) that stores computer-readable program code for the operation of the computing device. The computer-readable program code may be fixed, tangible, and stored in a computer-readable storage medium (e.g., removable disk, CD-ROM, ROM, fixed disk, USB drive) that can be directly read by these components. Further, it is understood that the computer-readable program may be stored as a computer program product comprising a computer-usable medium. Further, the persistent storage device may comprise computer-readable program code. Further, it is understood that the computer-readable program code and / or computer-usable medium may comprise non-transitory computer-readable program code and / or non-transitory computer-usable medium. Alternatively, the computer-readable program code may be stored remotely, but may be transmissible to these components via a modem or other interface device connected to a network (including, but not limited to, the Internet) via a transmission medium. The transmission medium may be any of a non-mobile medium (e.g., optical and / or digital and / or analog communication lines) or a mobile medium (e.g., microwave, infrared, free-space optical, or other transmission methods) or a combination thereof.

[0136] Those skilled in the art will understand that many more alternatives and modifications are possible and that the above examples are merely illustrative of one or more examples. Accordingly, the scope is limited only by the claims appended hereto.

Claims

1. A method for implementing a projector, comprising: a light modulator; a controller communicatively coupled thereto; an image source configured to provide and receive one or more image frames for driving the light modulator; and at least one light source arranged to irradiate the light modulator according to one or more colors, The method includes, for a predetermined image frame among the plurality of image frames and a predetermined color among one or more colors, determining, via the controller, a headroom of a highest luminance pixel of the predetermined image frame, the headroom representing a difference between a peak luminance related to a peak throughput of the light modulator and each highest luminance related to the highest luminance pixel; controlling, via the controller, a light source luminance of the at least one light source to a reduced light source luminance corresponding to a peak light source luminance reduced by the headroom; controlling, via the controller, a highest luminance region of the light modulator corresponding to the highest luminance pixel of the predetermined image frame to have the peak throughput; controlling, via the controller based on the reduced light source luminance, a lowest luminance region of the light modulator corresponding to a lowest luminance pixel of the predetermined image frame to respective low luminance throughputs that maintain a substantially constant predetermined low luminance output by the lowest luminance region of the light modulator over the plurality of image frames.

2. The method according to claim 1, wherein when the substantially constant predetermined low luminance is the reduced light source luminance, the substantially constant predetermined low luminance is obtained by adding, to a residual luminance of the light modulator in an off state, a luminance individually determined to reach the lowest luminance region to the substantially constant predetermined low luminance.

3. When the reduced light source luminance changes from image frame to image frame due to a change in the headroom, changing, for maintaining the lowest luminance of the lowest luminance region of the light modulator corresponding to the lowest luminance pixel of the predetermined image frame to the substantially constant predetermined low luminance, the respective low luminance throughputs, according to the method of claim 1.

4. For intermediate luminance pixels of the predetermined image frame, corresponding to respective intermediate luminances between a lowest luminance related to the lowest luminance pixel and a highest luminance related to the highest luminance pixel, Based on the value of the reduced light source luminance of the at least one light source, controlling each throughput of the intermediate luminance region of the light modulator corresponding to the intermediate luminance pixels of the predetermined image frame to each intermediate luminance throughput that maintains each substantially constant predetermined luminance output by the intermediate luminance region of the light modulator over the plurality of image frames, the method according to claim 1.

5. Controlling each throughput of the intermediate luminance pixels of the predetermined image frame to each intermediate luminance throughput between the low luminance throughput and the peak throughput as a function of each luminance associated with the intermediate luminance pixels, the method according to claim 1.

6. Controlling each throughput of the intermediate luminance pixels of the predetermined image frame linearly to each intermediate luminance throughput between the low luminance throughput and the peak throughput as a function of each luminance associated with the intermediate luminance pixels, the method according to claim 1.

7. The at least one light source includes a red laser, a green laser, and a blue laser, For each of the red laser, the green laser, and the blue laser, a respective headroom is determined, Each of the red laser, the green laser, and the blue laser is controlled according to the respective headroom of the red laser, the green laser, and the blue laser, The throughput of each of the highest luminance pixels and the lowest luminance pixels of red, green, and blue is controlled according to the respective headroom of the red laser, the green laser, and the blue laser, the method according to claim 1.

8. The light modulator is constituted by a digital micromirror device (DMD), the method according to claim 1.

9. Each of the respective highest luminances associated with the highest luminance pixels is less than the peak luminance, the method according to claim 1.

10. The lowest luminance pixels of the predetermined image frame correspond to black pixels, the method according to claim 1.

11. A projector, A light modulator, A controller coupled to be communicable, an image source configured to provide and receive one or more image frames for driving the optical modulator, and at least one light source arranged to irradiate the optical modulator according to one or more colors. For a predetermined image frame among the plurality of image frames and a predetermined color among the one or more colors, the controller determines the headroom of the highest luminance pixel of the predetermined image frame, and the headroom represents the difference between the peak luminance related to the peak throughput of the optical modulator and the respective highest luminance related to the highest luminance pixel. controls the light source luminance of at least one light source to a reduced light source luminance corresponding to the peak light source luminance reduced by the headroom. controls the highest luminance region of the optical modulator corresponding to the highest luminance pixel of the predetermined image frame to be the peak throughput. A projector that controls the lowest luminance region of the optical modulator corresponding to the lowest luminance pixel of the predetermined image frame to respective low luminance throughputs that maintain a substantially constant predetermined low luminance output by the lowest luminance region of the optical modulator over the entire plurality of image frames, based on the reduced light source luminance.

12. The projector according to claim 11, wherein when the substantially constant predetermined low luminance is the reduced light source luminance, it is the residual luminance in the off state of the optical modulator plus the individually determined luminance to reach the lowest luminance region to the substantially constant predetermined low luminance.

13. When the reduced light source luminance changes from the image frame to the image frame due to the change in the headroom, the controller is configured to change the respective low luminance throughputs to maintain the lowest luminance of the lowest luminance region of the optical modulator corresponding to the lowest luminance pixel of the predetermined image frame at the substantially constant predetermined low luminance, as claimed in claim 11.

14. The controller corresponds to each intermediate luminance between the lowest luminance related to the lowest luminance pixel and the highest luminance related to the highest luminance pixel for the intermediate luminance pixels of the predetermined image frame. Based on the value of the reduced light source luminance of the at least one light source, each throughput of the intermediate luminance region of the light modulator corresponding to the intermediate luminance pixels of the predetermined image frame is controlled to each intermediate luminance throughput that maintains a substantially constant predetermined luminance output by the intermediate luminance region of the light modulator over the entirety of the plurality of image frames. The projector according to claim 11.

15. Each throughput of the intermediate luminance pixels of the predetermined image frame is configured to be controlled to each intermediate luminance throughput between the low luminance throughput and the peak throughput as a function of the respective luminance associated with the intermediate luminance pixels. The projector according to claim 11.

16. Each throughput of the intermediate luminance pixels of the predetermined image frame is configured to be linearly controlled to each intermediate luminance throughput between the low luminance throughput and the peak throughput as a function of the respective luminance associated with the intermediate luminance pixels. The projector according to claim 11.

17. The at least one light source includes a red laser, a green laser, and a blue laser. A respective headroom is determined for each of the red laser, the green laser, and the blue laser. Each of the red laser, the green laser, and the blue laser is controlled in accordance with the respective headroom of the red laser, the green laser, and the blue laser. The respective throughputs of the highest luminance pixels and the lowest luminance pixels of each of red, green, and blue are controlled in accordance with the respective headrooms of the red laser, the green laser, and the blue laser. The projector according to claim 11.

18. The light modulator is constituted by a digital micromirror device (DMD). The projector according to claim 11.

19. Each of the respective highest luminances associated with the highest luminance pixels is less than the peak luminance. The projector according to claim 11.

20. The lowest luminance pixels of the predetermined image frame correspond to black pixels. The projector according to claim 11.

Images