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

Abstract

The invention relates to an apparatus, a system and a method for controlling a lowest brightness region of a light source and a light modulator. The projector includes a light modulator and a controller communicatively coupled to: an image source that provides a frame to drive light; and a light source arranged to illuminate the modulator according to a color. For a given image frame and a given color, the controller: determines a margin for a highest luminance pixel of the given frame, the margin representing a difference between a peak luminance of a peak throughput of the light modulator and a corresponding highest luminance associated with the highest luminance pixel; reducing the light source brightness to correspond to the peak light source brightness reduced by the margin; controlling the highest brightness region of the light modulator to a peak throughput; and based on the reduced light source brightness, the controller controls the lowest brightness region of the light modulator to a corresponding low brightness throughput that maintains a substantially constant given low brightness output by the lowest brightness region of the modulator across the plurality of frames.

Description

Technical Field

[0001] The present invention relates to apparatuses, systems, and methods for controlling the lowest brightness regions of light sources and light modulators. Background Art

[0002] Power consumption and heat generation at projectors (especially movie projectors) pose technical challenges that can be mitigated using various techniques, including dimming the light source for image frames that include the highest brightness pixels that are less than the peak possible brightness. However, such solutions may result in the lowest brightness and / or black pixels that change color as the brightness of the light source changes. Summary of the Invention

[0003] One aspect of the present invention provides a method implemented at a projector that includes a light modulator and a controller communicatively coupled to: an image source configured to perform one or more of providing an image frame and receiving an image frame to drive the light modulator; and at least one light source arranged to illuminate the light modulator according to one or more colors, the method including the steps of: for a given image frame of the image frames and a given color of the one or more colors: determining, via the controller, a margin of the highest brightness pixel of the given image frame, the margin representing a difference between a peak brightness associated with a peak throughput of the light modulator and a corresponding highest brightness associated with the highest brightness pixel; controlling, via the controller, the light source brightness of the at least one light source to a reduced light source brightness that corresponds to the peak light source brightness reduced by the margin; controlling, via the controller, the highest brightness region of the light modulator to the peak throughput corresponding to the highest brightness pixel of the given image frame; and based on the reduced light source brightness, controlling, via the controller, the lowest brightness region of the light modulator to a corresponding low brightness throughput corresponding to the lowest brightness pixel of the given image frame, the low brightness throughput maintaining a substantially constant given low brightness output by the lowest brightness region of the light modulator across the image frame.

[0004] Another aspect of the present invention provides a projector, the projector comprising: a light modulator; and a controller communicatively coupled to: an image source configured to perform one or more of providing and receiving 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, the controller being configured for a given image frame of the image frames and a given color of the one or more colors: determining a margin of the highest brightness pixel of the given image frame, the margin representing the difference between a peak brightness associated with a peak throughput of the light modulator and a corresponding highest brightness associated with the highest brightness pixel; controlling the light source brightness of the at least one light source to a reduced light source brightness, the reduced light source brightness corresponding to a peak light source brightness reduced by the margin; controlling the highest brightness region of the light modulator to a peak throughput corresponding to the highest brightness pixel of the given image frame; and based on the reduced light source brightness, controlling the lowest brightness region of the light modulator to a corresponding low brightness throughput corresponding to the lowest brightness pixel of the given image frame, the low brightness throughput maintaining a substantially constant given low brightness output by the lowest brightness region of the light modulator across the image frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] To better understand the various examples described herein and to more clearly show how they may be implemented, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0006] Figure 1 A system according to a non - limiting example is depicted.

[0007] Figure 2 A method of controlling a light source and a lowest brightness region of a light modulator according to a non - limiting example is depicted.

[0008] Figure 3 An example color vector of a projection pixel according to a non - limiting example is depicted.

[0009] Figure 4 Depicts a portion of a system before controlling a light source and a lowest brightness region of a light modulator for a given image frame Figure 1 thereof.

[0010] Figure 5 Depicts a portion of a system after controlling a light source and a lowest brightness region of a light modulator according to a given image frame Figure 4 thereof.

[0011] Figure 6 Depicts a system after controlling a light source and a lowest brightness region of a light modulatorFigure 5 part of the system, but for another image frame.

[0012] Figure 7 depicts, according to a non - limiting example, Figure 5 and Figure 6 an example color vector of the lowest - luminance pixels of the image frame in the example of

[0013] Figure 8 depicts, according to a non - limiting example, an example color vector of a projection pixel including a gain factor.

[0014] Figure 9 depicts, according to a non - limiting example, an example of controlling pixels of a light modulator to account for the relationship between luminance, residual luminance, and the control signal to the light modulator and how such relationships affect the throughput and / or light provided by the light modulator to the screen. Detailed Description

[0015] Power consumption and heat generation at a projector (especially a high - power / high - brightness movie projector) present technical challenges that can be mitigated using various techniques, including dimming the light source for an image frame that includes the highest - luminance pixels less than the peak possible luminance. However, such techniques may cause color changes in the lowest - luminance and / or black pixels. Thus, improved technical methods, apparatuses, and systems are provided herein for controlling the lowest - luminance regions of the light source and the light modulator.

[0016] Specifically, a projector for controlling the lowest - luminance regions of a light source and a light modulator is provided. The projector includes a light modulator and a controller communicatively coupled to: an image source that provides and / or receives one or more of image frames to drive the light modulator; and at least one light source arranged to illuminate 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 generally also includes projection optics that project the light of the at least one light source modulated by the light modulator into a projection image corresponding to the image frame, e.g., onto an object and / or a screen.

[0017] For a given image frame in an image frame and a given color among one or more colors, a controller generally: determines a margin of a highest brightness pixel of the given image frame, the margin representing a difference between a peak brightness associated with a peak throughput of a light modulator and a corresponding highest brightness associated with the highest brightness pixel; controls a light source brightness of at least one light source to a reduced light source brightness, the reduced light source brightness corresponding to a peak light source brightness reduced by the margin; and corresponding to the highest brightness pixel of the given image frame, controls a highest brightness region of the light modulator to a peak throughput.

[0018] In a specific example, for a given color, when the highest brightness pixel of a given image frame is at 90% of the peak brightness, the margin can be 10% (e.g., 100% minus 90%). When the light source of the given color is at 100% brightness, the light modulator can be controlled to 90% of the peak throughput (e.g., 90% duty cycle of a light modulator (such as a digital micromirror device (DMD) etc.) that operates according to pulse width modulation (PWM) etc.). However, operating the light source at 100% brightness results in power consumption and heat generation problems. Nevertheless, the margin allows dimming of the light source of the given color to achieve reduced power consumption and reduced heat generation.

[0019] For example, continuing with the example of a 10% margin, the light source of the given color can be reduced to a brightness corresponding to a peak light source brightness reduced by 10% of the margin. Accordingly, corresponding to the highest brightness pixel of the given image frame, the highest brightness region of the light modulator can be controlled to a peak throughput and / or a highest duty cycle. Thus, when projecting the given image frame (where the light source of the given color is dimmed to 90% of the peak brightness and the highest brightness region of the light modulator is controlled to a peak (e.g., 100%) throughput (e.g., duty cycle)), the highest brightness region of the corresponding projected image is at 90% brightness. This process can be referred to as dynamic dimming, and when the light source brightness is reduced, the power consumption and heat generation at the light source are also reduced.

[0020] However, this dimming of the light source affects other regions of the given image frame being projected. Specifically, the lowest brightness pixel (e.g., black pixel) of the given image frame will also have a reduced brightness, and thus when the brightness of the light source changes between image frames due to different margins in the image frame, the projected lowest brightness and / or black pixels will appear to change brightness frame by frame. Additionally, when this dynamic dimming occurs differently for red, green, and blue light sources, the projected lowest brightness and / or black pixels will not only appear to change brightness frame by frame but can also appear to change color.

[0021] Accordingly, the controller is typically also configured to control the lowest brightness and / or black regions of the light modulator to a corresponding low brightness throughput that maintains a generally constant given low brightness output across the image frame by the lowest brightness regions of the light modulator, corresponding to the lowest brightness and / or black pixels of a given image frame, based on a reduced light source brightness (e.g., from 100% to 90%).

[0022] In other words, and continuing with the 10% margin example, after reducing the light source of a given color by 10% (etc.), the controller can control the throughput (e.g., and / or duty cycle) of the lowest brightness and / or black regions of the light modulator to a value that maintains the same brightness across the lowest brightness and / or black regions between image frames. This control typically maintains the lowest brightness and / or black regions of the light modulator constant across the image frame such that the projected black pixels do not change color.

[0023] For example, when the light source brightness is at the reduced light source brightness, the generally constant given low brightness can include the residual brightness of the light modulator in the off state plus a corresponding brightness that determines the lowest brightness regions to reach the generally constant given low brightness. Thus, continuing with the 10% margin example, when the light source brightness is reduced by 10% (etc.), the residual brightness of the light modulator in the off state also generally decreases (e.g., by 10%).

[0024] In this way, to maintain a generally constant given low brightness (e.g., projected by the projector), the low brightness throughput (e.g., duty cycle) of the lowest brightness and / or black regions of the light modulator is typically controlled to a given value that increases the brightness of the projected lowest brightness and / or black pixels to the given value. For example, when the residual brightness of the light modulator in the off state generally decreases by 10%, the low brightness throughput (e.g., duty cycle) of the lowest brightness and / or black regions of the light modulator can be increased by a determined amount, which brings the projected brightness of the lowest brightness and / or black pixels back to the given value. This adjustment also occurs on a per-image-frame basis to maintain a generally constant given low brightness across multiple image frames.

[0025] Dimming of the light source is also understood to affect the brightness of the intermediate brightness pixels of a given image frame. Thus, the controller is also understood to control the corresponding throughput of the intermediate brightness pixels of a given image frame to a corresponding intermediate brightness throughput that is between the low brightness throughput and the peak throughput as a function of the corresponding brightness associated with the intermediate brightness pixels. Such a function can be a linear function, but can also be any suitable type of function.

[0026] Figure 1Illustrates system 100, which includes: a projector 102, the projector 102 includes a controller 104, a light modulator 106, and a memory 108, the memory 108 stores 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 at least one light source 114. The various components of the system 100 communicate via any suitable combination of wired communication links and / or wireless communication links, and the communication links between the components of the system 100 are Figure 1 shown in and depicted throughout the specification as bi-directional arrows between the various components.

[0027] As shown, the image source 112 may be communicatively coupled to an optional rendering device 116, and the image source 112 (as shown) may include a content player and / or a content generator. As shown, the rendering device 116 and the image source 112 may be combined into one device 118 (shown in dashed lines to indicate this optional combination of the rendering device 116 and the image source 112), however, in other implementations, 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, the pose data including at least data defining a geometric relationship, for example, between the projector 102 and an object projected by the projector 102 (such as a screen 120) (and / or any other suitable object, including an object on which projection mapping occurs). Generally, such pose data may include the position of the projector 102 (e.g., in "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 also include a camera for assisting in generating the pose data. Hereafter, for simplicity, reference will be made to projection onto the screen 120, although the projection may occur on any suitable object.

[0028] 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 can generally include two-dimensional images. The image source 112 can combine the image data 122 with 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) to produce an image frame 124 that includes the image data 122 that is altered for the perspective of the projection by the projector 102 onto the object. Alternatively, the image source 112 can receive the image frame 124 and "play" the image frame 124. Thus, the image source 112 is understood to perform one or more of generating the image frame 124 and receiving the image frame 124 and providing the image frame 124 to the controller 104 of the projector 102.

[0029] When the rendering device 116 and the image source 112 are separate, the rendering device 116 transfers the image data 122 to the image source 112, which processes and / or "plays" the image data 122 by producing an image frame 124 suitable for processing and projection by the projector 102.

[0030] The image data 122 can include, but is not limited to, AVI files, a series of JPG files, PNG files, etc. The image frame 124 can include, but is not limited to, high-definition multimedia interface (HDMI) data, digital video interface (DVI) data, DisplayPort (DP) data, Internet Protocol (IP)-based video data, video graphics array (VGA) data, and / or video transmission data.

[0031] When the rendering device 116 and the image source 112 are combined in the device 118, the device 118 can 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 transferred by the image source 112 to the projector 102, where the image frame 124 is used to control the projector 102 to project an image based on the image frame 124, for example, onto a two-dimensional or three-dimensional object such as the screen 120. The image frame 124 can include an image for projection onto the screen 120, for example, the image data 122 that is altered for the perspective of the projector 102 relative to the screen 120, as determined using the pose data and / or the object data; however, the image frame 124 can also include the pose data, the non-intrinsic characteristics of the projector 102, the settings of the projector 102, etc.

[0032] The rendering device 116 generally includes an image generator and / or a renderer (such as a computing device, a server, etc.), which is configured to generate and / or render an image as image data 122. Such image data 122 may include, but is not limited to, still images, videos, etc. In addition, although not shown, the rendering device 116 may communicate with an image generator and / or a memory that stores data (from which the image data 122 can be generated and / or rendered), and / or include an image generator and / or a memory that stores data. Alternatively, the rendering device 116 may use algorithms for generating images, etc. to generate the image data 122.

[0033] The image source 112 may include 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 image frames 124 for projection by the projector 102. Thus, the image source 112 may 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 combined into a device 118, the rendering of the image data 122 may be eliminated, and the device 118 renders the image frames 124 without generating the image data 122.

[0034] The projector 102 includes a projector configured to project the image frames 124, including but not limited to a digital projector, a movie 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 include 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 here, for simplicity, the light modulator 106 including a DMD will be referred to.

[0035] In addition, although only one projector 102 is described, the system 100 may include multiple projectors, each projector being configured to project corresponding projection data, including, for example, a portion of a larger tiled image to be projected.

[0036] Regardless of the technology used in the projector 102, it is assumed that the projector 102 and / or other projectors described herein include an image modulator, and the image modulator includes a plurality of individual pixel modulators; for example, when the projector includes a DMD projector, the image modulator includes a plurality of digital micromirrors, with one micromirror for each pixel of the image to be projected.

[0037] At least one light source 114 (which may be interchangeably referred to herein as light source 114 for simplicity) may include any suitable light source arranged to irradiate the light modulator 106 with light 126. For example, as shown, at least one light source 114 may be external to the projector 102, with holes in the projector 102 for receiving the light 126 and / or any suitable optics for providing the light 126 to the projector 102 between at least one light source 114. However, the light source 114 may also be incorporated into the projector 102.

[0038] In particular, the light source 114 may include a laser light source and / or any other light source whose brightness can be controlled by the controller 104. In some examples, the light source 114 may include 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 controlled to continuously irradiate the light modulator 106 with red light, green light, and blue light, and the controller 104 correspondingly controls the light modulator 106 to generate a red image frame, a green image frame, and a blue image frame in the projected modulated light 128 projected onto the screen 120 (etc.) via the projection optics 130 of the projector 102 (e.g., the projector 102 further includes the projection optics 130), where such projection is represented by the dashed line between the projection optics 130 and the screen 120.

[0039] Alternatively, the light 126 may be white, and the projector 102 may include suitable optics for separating the light 126 into red, green, and blue. Alternatively, although only one light modulator 106 is described, the projector 102 may include three light modulators 106, each dedicated to modulating red light, green light, and blue light, and the controller 104 controls the three light modulators 106 as described herein.

[0040] Although each of the rendering device 116, the image source 112 (and / or device 118), and the light source 114 is depicted as a component different from the projector 102, in other implementations, the corresponding portions of one or more 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.

[0041] Controller 104 may include a processor and / or multiple processors, including but not limited to one or more central processing units (CPUs) and / or one or more graphics processing units (GPUs) and / or one or more processing units; in either case, controller 104 includes hardware elements and / or a hardware processor. In some implementations, controller 104 may include an ASIC (application-specific integrated circuit) and / or an FPGA (field-programmable gate array) that is specifically configured to control the lowest brightness regions of the light source and the light modulator (such as light modulator 106). In fact, controller 104 may preferably not be a controller, but rather a controller that is specifically configured to implement a specific function for controlling the lowest brightness regions of the light source and the light modulator (such as light modulator 106). For example, controller 104 may specifically include a computer-executable engine configured to implement functions for controlling the light source and controlling the lowest brightness regions of the light modulator.

[0042] Memory 108 may include non-volatile storage units (e.g., erasable electronically programmable read-only memory (“EEPROM”), flash memory) and volatile storage units (e.g., random access memory (“RAM”)). The programming instructions implementing the functional teachings of projector 102 described herein are generally persistently held in memory 108 and used by controller 104, which appropriately utilizes the volatile memory during execution of such programming instructions. Those skilled in the art recognize that memory 108 is an example of a computer-readable medium that can store programming instructions executable on controller 104. Additionally, memory 108 is also an example of a memory unit and / or a memory module and / or a non-volatile memory.

[0043] Specifically, memory 108 stores one or more applications 110 (hereinafter referred to as applications 110 for simplicity), which, when processed by controller 104, enable controller 104 and / or projector 102 to implement the blocks of the methods described herein Figure 2 described.

[0044] Although not shown, projector 102 may also include any suitable wired or wireless communication interface that enables controller 104 to communicate with other components of system 100 that are external to projector 102. Such an interface or multiple interfaces may communicate in a wired and / or wireless manner as needed, including but not limited to using cables, WiFi TM communication links, Bluetooth TM communication links, personal area networks, local area networks, etc.

[0045] Now note Figure 2, which depicts a flowchart of a method 200 for controlling a light source and controlling a lowest brightness region of a light modulator according to a non-limiting example. Operations of the method 200 may correspond to machine-readable instructions executed by a projector 102, particularly a controller 104 of the projector 102. In the illustrated example, the instructions represented by the box of Figure 2 are stored at the memory 108 as an application 110, for example. Figure 2 The method 200 of Figure 2 is one way that the controller 104 and / or the projector 102 and / or the system 100 may be configured. Additionally,

[0046] Figure 2 The method 200 of

[0047] Figure 2 need not be executed in the exact order shown, and likewise, the individual boxes may be executed in parallel rather than sequentially. Accordingly, the elements of the method 200 are referred to herein as "boxes" rather than "steps".

[0048] At block 202, for a given image frame 124 in the image frames 124 and a given color among one or more colors generated by the light source 114, the controller 104 and / or the projector 102 determine a margin of the highest brightness pixel of the given image frame 124, where the margin represents the difference between a peak brightness associated with a peak throughput of the light modulator 106 and a corresponding highest brightness associated with the highest brightness pixel. It should also be understood that the remaining blocks of the method 200 are implemented with respect to the given image frame 124 and the given color of block 202.

[0049] As used herein, the term "peak throughput" is understood to include the state in which the light modulator 106 is controlled (e.g., by the controller 104) such that its pixels provide the maximum amount of light from the light source 114 to the screen 120. Similarly, the pixels of the light modulator 106 being controlled to peak throughput can include the state in which the pixel is controlled such that the pixel provides the maximum amount of light from the light source 114 to the screen 120. Similarly, the pixels of the light modulator 106 being controlled to minimum throughput can include the state in which the pixel is controlled such that the pixel provides the minimum amount of light from the light source 114 to the screen 120. The throughput of a pixel can be between the minimum throughput and the peak throughput.

[0050] It should be understood that the corresponding maximum brightness associated with the highest brightness pixels is typically less than the peak brightness (e.g., otherwise the margin would be 0%).

[0051] In block 204, the controller 104 and / or the projector 102 controls the light source brightness of at least one light source 114 to a reduced light source brightness that corresponds to the peak light source brightness reduced by the margin.

[0052] In block 206, the controller 104 and / or the projector 102 controls the highest brightness region of the light modulator 106 to peak throughput corresponding to the highest brightness pixels of a given image frame 124.

[0053] In block 208, the controller 104 and / or the projector 102 controls the lowest brightness region of the light modulator 106 to a corresponding low brightness throughput based on the reduced light source brightness, corresponding to the lowest brightness pixels of a given image frame 124, the low brightness throughput maintaining a generally constant given low brightness output by the lowest brightness region of the light modulator 106 across the image frame 124.

[0054] It should be understood that the lowest brightness pixels of a given image frame 124 can correspond to black pixels.

[0055] It should also be understood that the method 200 can occur, for example, in parallel for multiple given image frames 124 and for all one or more colors produced by the light source 114, such that for the projected pixels, for all one or more colors, a corresponding generally constant given low brightness is maintained during all image frames 124 of the corresponding lowest brightness pixels of the one or more colors, such that the brightness and color of the corresponding lowest brightness pixels projected do not change during multiple image frames 124.

[0056] It should also be understood that method 200 can be implemented dynamically, for example, when receiving image frame 124, and / or method 200 can be implemented before projecting image frame 124, where various corresponding reduced light source brightnesses of image frame 124 determined at blocks 202, 204 are stored at memory 108 (e.g., as a module of application 110) in association with the corresponding low brightness throughput determined at block 208, and the low brightness throughput maintains a substantially constant given low brightness output by the lowest brightness region of the light modulator across multiple image frames 124.

[0057] It should also be understood that for a given color, the lowest brightness pixel is the same lowest brightness across multiple image frames 124. Thus, for example, when one image frame 124 has a lowest brightness pixel of "0" (e.g., black, 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 brightness pixel of "1" (e.g., gray scale), the lowest brightness pixel of the second image frame 124 is considered an intermediate brightness pixel. However, when all image frames 124 do not have a lowest brightness pixel of "0" such that the lowest brightness is "1", a pixel with this brightness of "1" is considered the lowest brightness pixel.

[0058] However, it should be understood that method 200 can be implemented for intermediate brightness pixels such that controller 104 controls the intermediate brightness region (with a given intermediate brightness) of the light modulator to a corresponding intermediate brightness throughput corresponding to the intermediate brightness pixels of a given image frame, and the intermediate brightness throughput maintains a substantially constant given intermediate brightness output by the intermediate brightness region of the light modulator across multiple image frames.

[0059] In other words, the lowest brightness pixels projected with a brightness of "1" are controlled to the same projected brightness across multiple image frames 124.

[0060] Method 200 can include other features.

[0061] For example, when the light source brightness is at a reduced light source brightness, the substantially constant given low brightness of block 208 can include the residual brightness of light modulator 106 in the off state plus the corresponding brightness determined to bring the lowest brightness region to the substantially constant given low brightness.

[0062] For example, referring next to Figure 3 , which depicts an example color vector 300 of a projected pixel in a tristimulus space (Φ 3 ). Vector 300 can represent the projected lowest brightness pixel, or the projected highest brightness pixel of a given image frame 124, or a projected intermediate brightness pixel (e.g., having an intermediate brightness between the projected lowest brightness pixel and the projected highest brightness pixel).

[0063] The vector 300 can be represented as:

[0064]

[0065] In Equation (1), is the vector 300, and is the direction of the vector 300 in the tristimulus space (Φ 3 ).

[0066] Also in Equation (1), "thrpt" is the throughput of the pixel of the light modulator 106 that generates the vector 300, and can be a value between 0 and 1 (or between 0% and 100% and / or between 0 and 100, and / or any other suitable ratio), which represents the portion of the time that the pixel of the light modulator 106 is "on", etc. in a given image frame 124. Thus, for a "thrpt" value of "0", the pixel of the light modulator 106 is "off" for the entire given image frame 124, and can generate a black projection pixel and / or a projection pixel with the lowest brightness. Similarly, for a "thrpt" value of "1", the pixel of the light modulator 106 is "on" for the entire given image frame 124, and can generate a white projection pixel with the highest brightness and / or a color projection pixel. For a "thrpt" value between "0" and "1", the pixel of the light modulator 106 is "on" for a portion of the given image frame 124, and can generate a gray projection pixel and / or a color projection pixel with an intermediate brightness. For a DMD and / or any other type of light modulator 106 that operates according to PWM (e.g., DMD), the throughput can alternatively be referred to as the duty cycle. However, for other types of light modulators 106 that do not operate according to PWM (e.g., LCD-based light modulators and / or LCOS light modulators), the term "throughput" can be used (e.g., LCD-based light modulators and / or LCOS light modulators do not operate according to the duty cycle).

[0067] Also in Equation (1), "Bright" is the brightness of the light 126 of the color of the light source 114 that irradiates the pixel of the light modulator 106, and can be a value between 0% and 100% (e.g., where 0% means the light source 114 is off, and 100% means the light source is at peak or maximum brightness). However, the value of "Bright" can be between 0 and 1, or between 0 and 100, or any other suitable scale.

[0068] Therefore, the term "thrpt*Bright" is understood to represent the brightness of the projection pixel represented by the vector 300 due to the interaction of the light 126 with the pixel of the light modulator 106.

[0069] Also in Equation (1), Ro is the residual luminance of the light modulator 106 that is in the off state when the light modulator 106 is irradiated with light 126. Thus, when the throughput is "0", the residual luminance Ro generally represents the luminance of a black projection pixel. In the examples described herein, Ro can be 0.001. The unit of Ro and / or the residual luminance can be the same unit as the luminance "Bright" in Equation (1), and (e.g., vector 300) can be in any suitable unit (e.g., while and / or vector 300 can be expressed as a percentage), such as "thrpt*Bright", and Ro can be expressed as a percentage, which can be, for example, by and / or multiplying the value of vector 300 by the maximum measure of the light source 114 in lux to convert to any suitable measure unit (such as, lux). However, for example, when performing its determination, and / or vector 300 can be unitless.

[0070] Thus, in Figure 3 vector 300 is understood as vector and vector sum.

[0071] However, since the luminance "Bright" of the light 126 may change due to variations in the margin (e.g., at block 204), the residual luminance Ro can change from image frame 124 to image frame 124.

[0072] Therefore, referring to Equation (1), and assuming is a given low luminance that is approximately constant for block 208 of method 200, as the residual luminance Ro changes from image frame 124 to image frame 124, and as the luminance "Bright" of the light 126 changes from image frame 124 to image frame 124, the throughput "thrpt" is controlled from image frame 124 to image frame 124 to a value that maintains at a constant value for the lowest luminance pixels from image frame 124 to image frame 124.

[0073] In other words, at least block 208 of method 200 results in a change in the black dots of the projector 102. In particular, the black dots of the projector 102 can become brighter because for the black pixels in the image frame 124, "black" no longer corresponds to the residual luminance, but rather to the residual luminance with the term "thrpt*Bright" added to maintain a constant value (e.g., a constant black dot) for the black pixels across the image frame 124. Thus, in exchange for reduced power usage and heat generation, there is a trade-off with brighter black dots.

[0074] In addition, it should be understood that for a set of image frames 124, the black dots of the black pixels can be based on the image frame 124 with the smallest margin. As the smallest margin decreases, the black dots (e.g., ) increase among the set of image frames 124. In other words, using a specific example, the first set of image frames 124 with a smallest margin of 5% will have black dots that are brighter than those of the second set of image frames 124 with a smallest margin greater than 5%.

[0075] In other words, method 200 may further include: when the reduced light source brightness changes frame by frame for each image frame 124 due to the change in margin, the controller 104 and / or the projector 102: corresponding to the lowest brightness pixel of a given image frame 124, change the corresponding low brightness throughput to maintain a substantially constant given low brightness in the lowest brightness region of the light modulator 106. In this way, the brightness and color of the projected lowest brightness pixels are maintained across the image frames 124.

[0076] A similar process can occur for the intermediate brightness pixels such that the projected intermediate brightness pixels corresponding to the intermediate brightness pixels having the same brightness across the image frames 124 do not change in brightness or color across the image frames 124.

[0077] However, a function can also be used to control the intermediate brightness pixels. For example, method 200 may further include: for the intermediate brightness pixels of a given image frame 124, corresponding to the respective intermediate brightness between the lowest brightness associated with the lowest brightness pixels and the highest brightness associated with the highest brightness pixels, the controller 104 and / or the projector 102: based on the value of the reduced light source brightness of at least one light source 114, control the respective throughput of the intermediate brightness region of the light modulator 106 corresponding to the intermediate brightness pixels of the given image frame 124 to a respective intermediate brightness throughput, and the respective intermediate brightness throughput maintains a substantially constant respective given brightness output by the intermediate brightness region of the light modulator 106 across the image frames 124.

[0078] Method 200 may further include: the controller 104 and / or the projector 102: control the respective throughput of the intermediate brightness pixels of a given image frame 124 to a respective intermediate brightness throughput between the low brightness throughput and the peak throughput as a function of the respective brightness associated with the intermediate brightness pixels.

[0079] For example, such a function can be linear, or can be any suitable function.

[0080] When the function is linear, method 200 may further include: controller 104 and / or projector 102: linearly controlling the respective throughput of the intermediate luminance pixels of a given image frame 124 to a respective 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.

[0081] Using the linear example and referring to Equation (1), assume is the given luminance of the projected intermediate luminance pixel associated with a given intermediate luminance pixel of image frame 124, control the throughput of the pixels of light modulator 106 such that in Equation (1), for the same intermediate luminance across image frame 124, the term "thrpt*Bright" results in the same value. However, for different margins, the luminance variation of light 126 is generally known and can be linearly reduced as a function of the margin. Thus, when "Bright" is linearly reduced, in Equation (1), for a given intermediate luminance, "thrpt" can be linearly increased. However, in some examples, when "Bright" is linearly reduced, in Equation (1), "thrpt" may not increase linearly. This situation is described below with reference to Figure 9 and other equations (such as Equations (7) to (11)), which better consider the relationship between luminance, residual luminance, and the control signal to the light modulator, and how this relationship affects the throughput and / or light provided by the light modulator to screen 120. Figure 1 ).

[0082] However, it should also be understood that such examples have been simplified for illustrative purposes, and matrix techniques can be used to determine For example, consider any other suitable factors that may contribute to the luminance of the projected pixels, including but not limited to, diffraction differences due to spatial patterning at light modulator 106 when light modulator 106 includes a DMD, and changes in residual luminance due to changes in throughput.

[0083] In addition, in some examples, at least one light source 114 can include a red laser, a green laser, and a blue laser, and method 200 can occur in parallel for the red laser, the green laser, and the blue laser. For example, the respective margins of each of the red laser, the green laser, and the blue laser can be determined based on, for example, the red image frame component, the green image frame component, and the blue image frame component of a given 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 based on the respective margin of each of the red laser, the green laser, and the blue laser (e.g., at block 204 of method 200). Additionally, in these examples, the respective throughput of the respective highest brightness pixels and the respective lowest brightness pixels of each of the colors red, green, and blue is controlled based on the respective margin of each of the red laser, the green laser, and the blue laser (e.g., at blocks 206 and 208 of method 200).

[0084] Next, note Figure 4 、 Figure 5 、 Figure 6 which depict a portion of system 100 operating in different modes, and at least Figure 5 and Figure 6 depict examples of method 200. Specifically, Figure 4 depicts a portion of system 100 operating without implementing method 200 (e.g., without dynamic dimming), while Figure 5 and Figure 6 depict a portion of system 100 operating while implementing method 200 (e.g., with dynamic dimming). Although not all components of system 100 are depicted in Figure 4 、 Figure 5 and Figure 6 it should still be understood that such components exist.

[0085] In addition, Figure 4 and Figure 5 show the same image frame 124-1 of a test pattern having four pixel bands corresponding to the highest brightness pixels at 90% brightness, 60% brightness, 30% brightness, and 0% brightness.

[0086] Figure 6 shows another image frame 124-2 of another test pattern having four pixel bands corresponding to the highest brightness pixels at 60% brightness, 30% brightness, 10% brightness, and 0% brightness.

[0087] In Figure 4 、 Figure 5 and Figure 6Among them, the highest luminance pixels of each image frame 124 are understood to be less than 100% of the peak luminance, and the lowest luminance pixels of each image frame 124 are understood to be black pixels.

[0088] First, turn to Figure 4 , in the depicted mode, the system 100 can operate without dynamic dimming, where the regions of the light modulator 106 corresponding to the four bands of the image frame 124-1 are controlled to the respective throughputs corresponding to the luminance of the four pixel bands (e.g., 0.9, 0.6, 0.3, and 0), and the light source 114 is controlled to 100% of the peak luminance.

[0089] In this way, the modulated light 128 projected onto the screen 120 generates a projected image 402 including the four bands of the image frame 124-1.

[0090] However, further referring to Equation (1), the residual luminance Ro1 of the region of the light modulator 106 controlled to a 0 throughput is understood to contribute to the luminance of the black band of the projected image 402, as indicated, for example, by the text "0 throughput (+Ro)" at the light modulator 106 and the text "0% +Ro)" at the projected image 401. Although such residual luminance Ro1 also contributes to other pixel bands of the projected image 402, the higher the luminance, the less obvious the residual luminance Ro1. Therefore, for simplicity, the residual luminance Ro is omitted in the regions of the light modulator 106 corresponding to the non-lowest luminance pixels of the image frame 124-1.

[0091] Next, refer to Figure 5 . In the depicted mode, the system 100 can operate by dynamic dimming. Therefore, Figure 5 Similar to Figure 4 , but the controller 104 implements method 200.

[0092] In these examples, since the peak luminance region of the image frame 124-1 (e.g., the same image frame as in Figure 4 ) is 90%, there is a 10% margin (e.g., as determined in block 202 of method 200). In this way, the light source 114 is controlled (e.g., as determined in block 204 of method 200) to a reduced luminance of 90%, and the regions of the light modulator 106 corresponding to the four bands of the image frame 124-1 are controlled (e.g., as determined in block 206 of method 200) to the respective throughputs that generate a projected image 502 similar to the projected image 402 at least in the corresponding 90%, 60%, and 30% regions.

[0093] For example, the throughput of the region of the light modulator 106 corresponding to the "90%" highest brightness pixels of a given image frame 124-1 is controlled to be "1", the throughput of the region of the light modulator 106 corresponding to the "60%" next highest brightness pixels of a given image frame 124-1 is controlled to be "0.67", and the throughput of the region of the light modulator 106 corresponding to the "30%" next highest brightness pixels of a given image frame 124-1 is controlled to be "0.33".

[0094] Specifically, ignoring the residual brightness and using Equation (1), for the highest brightness pixels "90%" of a given image frame 124-1, it should be understood that Figure 4 the term "thrpt*Bright" in the example of is "0.9*100%" (e.g., thrpt = 0.9 and Bright = 100%) or 90%, and similarly, for Figure 5 the example of, the term "thrpt*Bright" is "1*90%" (e.g., thrpt = 1 and Bright = 90%) or 90%.

[0095] Similarly, for the next highest brightness pixels "60%" of a given image frame 124-1, Figure 4 the term "thrpt*Bright" in the example of is "0.6*100%" (e.g., thrpt = 0.6 and Bright = 100%) or 60%, and similarly, for Figure 5 the example of, the term "thrpt*Bright" is "0.67*90%" (e.g., thrpt = 0.67 and Bright = 90%) or 60%.

[0096] Similarly, for the next highest brightness pixels "30%" of a given image frame 124-1, Figure 4 the term "thrpt*Bright" in the example of is "0.3*100%" (e.g., thrpt = 0.3 and Bright = 100%) or 30%, and similarly, for Figure 5 the example of, the term "thrpt*Bright" is "0.33*90%" (e.g., thrpt = 0.33 and Bright = 90%) or 30%.

[0097] Therefore, in the example of Figure 5 compared with the example of Figure 4 the reduced brightness of the light source 114 and thus the reduced power consumption and the increased throughput in the light modulator 106 can achieve similar and / or the same results to achieve similar projected images 402, 502.

[0098] However, for the lowest luminance region of a given image frame 124-1, each region of the light modulator 106 is controlled (e.g., as determined in block 208 of method 200) to a throughput of 0.010, and since such throughput is low compared to the throughput of other regions, the residual luminance is understood to contribute more significantly to the luminance of the corresponding projected image 502. It should be understood that the throughput of 0.010 is selected to achieve the following constant given low luminance for the corresponding projected image 502:

[0099]

[0100] Equation (2) is understood to be the same as Equation (1), but the term is selected to be constant among multiple image frames 124, and where "thrpt1" is the throughput of each region of the light modulator 106 corresponding to the lowest luminance region of a given image frame 124-1, Ro1 is the residual luminance of such each region of the light modulator 106, and "Bright1" is the luminance of the light 126 illuminating the light modulator 106 (e.g., Bright1 = 90%). is the same as in Equation (1). Ro1 can be determined by multiplying Ro in Equation (1) by a gain factor such as 90%, and such a gain factor can generally include 100% reduced by a margin (e.g., 10%).

[0101] It should also be understood that the value of the term is greater than Figure 4 for the same lowest luminance region of the projected image 402, however, among multiple image frames 124, the term is selected to be the same. Thus, according to the terms "Bright1" and "Ro1", the throughput "thrpt1" of each region of the light modulator 106 corresponding to the lowest luminance region of a given image frame 124-1 is determined. For example, using the absolute value of Equation (2) (e.g., ignoring the term ), the throughput "thrpt1" can be determined from the following equation:

[0102] thrpt1 = (R Black -Ro1) / Bright1 Equation (3)

[0103] In addition, R black is understood to be greater than (0% + Ro) and / or brighter than the corresponding band of the projected image 402.

[0104] Now turning to Figure 6, the controller 104 continues to implement method 200 for another image frame 124-2 (however, with pixels having brightnesses of 60%, 30%, 10%, and 0%) to generate a projected image 602. Thus, the margin is 40% (e.g., 100% minus 60%), and the controller 104 can control the light source 114 to a brightness of 60% (e.g., 100% minus the margin (40%)).

[0105] In this way, the regions of the light modulator 106 corresponding to the four bands of the image frame 124-2 are controlled (e.g., as determined in block 206 of method 200) to the corresponding throughputs for generating the projected image 602.

[0106] For example, the throughput of the region of the light modulator 106 corresponding to the "60%" highest-brightness pixels 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-brightness pixels of "30%" of a 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-brightness pixels of "10%" of a given image frame 124 is controlled to "0.16".

[0107] Specifically, ignoring the residual brightness and using Equation (1), for the highest-brightness pixels "60%" of a given image frame 124-2, it should be understood that for Figure 6 the example of, the term "thrpt*Bright" is "1*60%" (e.g., thrpt = 1 and Bright = 60%) or 60%, which is the same for a throughput of 0.6 and a brightness of 100% (e.g., when the system 100 operates without dynamic dimming).

[0108] Compare this example with Figure 5 the example of, for the region of the image modulator 106 corresponding to the 60% brightness region of the image frame 124-1, due to the reduced brightness of the light source 114, the throughput increases from 0.67 to 1. Thus, the corresponding "60%" bands in the projected images 502, 602 have the same and / or similar brightness because they each have a brightness of 60%. It should also be understood that these calculations are simplified, and matrix calculations can be performed to account for other factors, such as changes in residual brightness due to Figures 5 to 6 the reduced brightness of the light 126 from

[0109] Similarly, for the next-highest-brightness pixels "30%" of a given image frame 124, for Figure 6For example, the term "thrpt*Bright" is "0.5*60%" (e.g., thrpt = 0.5 and Bright = 60%) or 30%, which is the same for throughput 0.3 and brightness 100% (e.g., when system 100 operates without dynamic dimming).

[0110] Compare this example with Figure 5 For the region of image modulator 106 corresponding to the 30% brightness region of image frame 124-1, due to the reduced brightness of light source 114, the throughput increases from 0.33 to 0.5. Thus, the corresponding "30%" bands in projected images 502, 602 have the same and / or similar brightness because each has a brightness of 30%. It should also be understood that these calculations are simplified, and matrix calculations can be performed to account for other factors, such as changes in residual brightness due to the reduced brightness of light 126 from Figures 5 to 6 and other factors.

[0111] Similarly, for the next highest brightness pixel "10%" of a given image frame 124, for Figure 6 the example, the term "thrpt*Bright" is "0.16*60%" (e.g., thrpt = 0.16 and Bright = 60%) or 10%, which would be the same for throughput 0.1 and brightness 100% (e.g., when system 100 operates without dynamic dimming).

[0112] However, for the lowest brightness region of a given image frame 124-2, the respective regions of light modulator 106 are controlled (e.g., as determined in block 208 of method 200) to a throughput of 0.014, and since such throughput is low compared to the throughput of other regions, the residual brightness is understood to contribute more significantly to the brightness of the corresponding projected image 602. It should be understood that a throughput of 0.0155 is selected to achieve the following constant given low brightness for the corresponding region of projected image 602:

[0113]

[0114] Equation (4) is understood to be the same as equation (2), and the term has the same value as equation (2) (e.g., is selected to be constant among multiple image frames 124), and where "thrpt2" is the throughput of the respective regions of light modulator 106 corresponding to the lowest brightness region of a given image frame 124-2, and Ro2 is the residual brightness of these corresponding regions of light modulator 106 (e.g., but due to light from Figures 5 to 6the brightness of the light 126 decreases and thus decreases relative to Equation (2)), and "Bright2" is the brightness of the light 126 that irradiates the light modulator 106, but decreases relative to Equation (2) (e.g., due to Figures 5 to 6 the brightness of the light 126 decreases). The same as in Equation (1) and Equation (2). Ro2 can be determined by multiplying Ro in Equation (1) by a gain factor (such as 60%), and such a gain factor can generally include a 100% reduction with a margin (e.g., 40%).

[0115] It should also be understood that the term has the same value as in Equation (2), and according to the terms “Bright2” and “Ro2”, the throughput “thrpt2” of each region corresponding to the lowest brightness region of the given image frame 124-2 of the light modulator 106 is determined. For example, using the absolute value of Equation (4) (e.g., ignoring the term ), the throughput “thrpt2” can be determined from the following equation:

[0116] thrpt2 = (R Black -Ro2) / Bright2 Equation (5)

[0117] Therefore, by correspondingly selecting the value of the term “thrpt2” and correspondingly controlling the throughput of each region corresponding to the lowest brightness region of the given image frame 124-2 of the light modulator 106 to such a value, the brightness of the lowest brightness region of the projected image 602 is controlled to be the same as the brightness of the lowest brightness region of the projected image 502.

[0118] For example, for Equation (2) and Equation (4), using the corresponding throughputs 0.010 and 0.0155, the corresponding brightnesses 90% and 60%, and the corresponding residual brightnesses 0.09 and 0.06 (e.g., using Ro of 0.001), Ro1 can include Ro multiplied by a gain factor of 90%, Ro2 can include Ro multiplied by a gain factor of 60%), and the value of R black is the same value of 0.99.

[0119] This is further explained in Figure 7 which depicts the Figure 7 vectors 700-1, 700-2 for each of Equation (2) and Equation (4), and the vectors 700-1, 700-2 are similar to the vector 300. The vectors 700-1, 700-2 are similar to the vector 300.

[0120] Specifically, as already explained, the residual luminance Ro1 of vector 700-1 is greater than the residual luminance Ro2 of vector 700-2. Therefore, to make vectors 700-1 and 700-2 have the same value, the corresponding throughputs of thrpt1 and thrpt2 are controlled such that the corresponding terms "thrpt1*Bright1" and "thrpt2*Bright2" added to the corresponding residual luminances Ro1 and Ro2 produce the same value A similar determination can occur for any intermediate luminance pixel and in fact any highest luminance pixel, such that the projection pixels associated with the same luminance pixels of image frame 124 are projected with the same luminance, regardless of the luminance of light 126.

[0121] Next note Figure 8 , Figure 8 depicts another vector 800 defined by Equation (6):

[0122]

[0123] However, the term "g" in Equation (6) modifies the sum of (thrpt*Bright+Ro). The term "g" can be a gain factor between 0 and 1, indicating the amount by which light source 114 is dimmed. Thus, Equation (6) can be a more general version of Equation (1) (e.g., and / or Equation (2) and / or Equation (4)), assuming that in Equation (6), the term "Bright" is understood as 100% (e.g., 100% output of light source 114), and the term Ro is understood as the residual luminance when the output of light source 114 is 100%. In fact, as described above, Ro1 and Ro2 can be determined by multiplying Ro by the corresponding gain factors 0.9 and 0.6. The term "thrpt" can be variable, e.g., to maintain a constant value Because the gain factor is reduced from "1" to less than "1".

[0124] For example, for g = 0.9, light source 114 can be dimmed by 10%, such that the output of light source 114 is 90%, and the residual luminance Ro is dimmed by the same amount. In this way, for a set of vectors representing the luminance of the projection pixels of image frame 124 By reducing "g" from 1 to a value less than 1 by controller 104, all the vectors are dimmed accordingly, and the corresponding throughputs are adjusted to maintain the corresponding values of the set of vectors

[0125] ​It should also be understood that when the light source 114 is dimmed, more contrast levels can be obtained at lower projection brightness, because the same change in throughput at 100% brightness of the light source 114 and a brightness below 100% of the light source 114 can result in a smaller change in projection brightness. For example, for a 0.1 change in throughput at 100% brightness of the light source 114, the projection brightness changes by 10%, while for a 0.1 change in throughput at 50% brightness of the light source 114, the projection brightness changes by 5%. Therefore, during dynamic dimming and / or during the implementation of method 200, more grayscales can be obtained. In fact, after dimming the light source 114, the controller 104 can increase the available grayscales of the image frame 124, although in some examples, such an increase can occur when such dimming on a part of the image frame 124 corresponding to a scene (e.g., a scene of a video) is consistent to ensure that the change in grayscale levels does not fluctuate on that scene. For example, a file corresponding to the image frame 124 can be received and processed by any suitable component of the system 100 (e.g., the controller 104 and / or any component of the device 118) to determine the image frame 124 corresponding to the scene to which the method 200 can be applied to apply dynamic dimming, and accordingly add grayscale levels to the image frame 124 (e.g., by adjusting such an image frame 124 to include more grayscale levels than in the original image frame 124, etc.).

[0126] Next note Figure 9 , Figure 9 shows the percentage brightness change of the incident light (e.g., from the light source 114) provided by the pixels of the light modulator 130 to the screen 104 when the controller 104 outputs a control signal to the light modulator, and this control signal attempts to control the throughput of the light modulator between 0% and 100% (and / or as shown, between 0 and 1, such that the control signal is dimensionless). As shown, at a throughput of 0% (e.g., the pixel is controlled to pure black), a residual brightness Ro of 5% of the light from the light source 114 is still provided by the light modulator 130 to the screen 120. In fact, a residual brightness Ro of 5% is maintained for all throughputs from 0% to 100%. However, at a throughput of 100%, the brightness of the light from the light source 114, the modulation depth R1 of the light modulator (which represents the light available for modulation) is only 95% of the light from the light source 114 (e.g., 100% minus 5% of the residual brightness Ro). Therefore, it should be understood that Ro and R1 can be constants, and in a simple model, R1 = 100% - Ro.

[0127] In addition, the brightness output by the light modulator 130 can be represented by a scalar term (e.g., ignoring the vectors mentioned above):

[0128] L = (R1 x C + Ro) * S Equation (7)

[0129] In Equation (7), L is the light generated by the pixels of the light modulator 130 (e.g., as provided to the screen 120), Ro is the residual luminance (e.g., 5% as in Figure 9 ), R1 is the modulation depth (e.g., the percentage of the modulated light output by the light modulator 130, and it can be a constant defined by 100% - Ro), C is the value of the control signal for controlling the throughput (e.g., and can be in the range of 0 to 1, corresponding to 0% throughput to 100% throughput as in Figure 9 ), and S is the percentage luminance of the light output by the light source 114.

[0130] As described herein, the light output by the pixels of the light modulator 130 is the same under conditions "A" and "B". For example, under condition A, the control signal can be C A , and the percentage luminance of the light output by the light source 114 can be S A ; for example, condition A can be used for the normal operation where the light source 114 is controlled to 100%. Similarly, under condition B, the control signal can be C B , and the percentage luminance of the light output by the light source 114 can be S B ; for example, condition B can be the condition where the light source 114 is dimmed. For these two conditions, Equation (7) can be rewritten as (e.g., for the light L A , L B ) generated by the pixels of the light modulator 130 under conditions A and B respectively):

[0131] L A = (R1 x C A + Ro) * S A Equation (8)

[0132] L B = (R1 x C B + Ro) * S B Equation (9)

[0133] Setting Equation (8) and Equation (9) equal, L A , L B are equal under conditions A and B:

[0134] (R1 x C A + Ro) * S A = (R1 x C B + Ro) * S B Equation (10)

[0135] Solving for C A :

[0136]

[0137] Assume that condition A is the brightness S of light source 114 B is 100%, but the control signal C A is below 100%, and in condition B, the brightness S of light source 114 B has been reduced from 100% based on a margin (e.g., according to block 202 of method 200), and the control signal C for maintaining the same brightness (e.g., as in blocks 206 and 208 of method 200, but for the highest brightness pixels and lower brightness pixels) can be determined according to equation (11). B For example, for the highest brightness pixels, C B can be used to determine (is set to the control signal for controlling the pixels of light modulator 114 to the highest brightness), while for the lowest brightness pixels, C A can be used to determine (is set to the control signal for controlling the pixels of light modulator 114 to the lowest brightness). B can be used to determine (is set to the control signal for controlling the pixels of light modulator 114 to the lowest brightness). A can be used to determine (is set to the control signal for controlling the pixels of light modulator 114 to the lowest brightness).

[0138] In fact, equation (11) shows the relationship between brightness, residual brightness, and the control signal to the light modulator, and how this relationship affects the throughput provided by the light modulator to screen 120 and / or the light may not be strictly linear.

[0139] As should now be clear, the operation and function of the devices described herein are complex enough that their implementation on a computer system is required, and as a practical matter, cannot be performed in the human mind. In particular, computing devices such as those set forth herein are understood to require and provide speed, accuracy, and complexity management that cannot be achieved by human intellectual steps, in addition to the inherent digital nature of these operations (e.g., the human intellect cannot directly interface with a digital projector, project light, or adjust the throughput of a light modulator, etc.).

[0140] It should also be understood that examples of the term "configured to" (such as "a computing device configured to...", "a processor configured to...", "a controller configured to...", etc.) can be understood to include the characteristics of a computer-readable storage medium having program instructions stored thereon, which when executed by the computing device and / or processor and / or controller, etc., can cause the computing device and / or processor and / or controller to perform a set of operations that can include the characteristics that the computing device and / or processor and / or controller, etc., are configured to implement. Thus, the term "configured to" is understood not to be unduly limited to the means-plus-function interpretation, etc.

[0141] In addition, the description of a processor and / or a controller and / or a device and / or an engine, etc. configured to perform certain functions is understood to include, but is not limited to, more than one processor and / or more than one controller and / or more than one device and / or more than one engine, etc. that perform such functions.

[0142] It should be understood that, for the purposes of this specification, the language "at least one of X, Y, and Z" and "one or more of X, Y, and Z" can be interpreted as only X, only Y, only Z, or any combination of two or more of the items X, Y, and Z (e.g., XYZ, XY, YZ, XZ, etc.). Similar logic can be applied to two or more items in any occurrence of the language "at least one" and "one or more".

[0143] The terms "about", "substantially", "essentially", "approximately", etc. are defined as "close to", for example, as understood by those skilled in the art. In some examples, the term should be understood to be "within 10%", in other examples, "within 5%", in other examples, "within 1%", and in other examples, "within 0.5%".

[0144] Those skilled in the art will appreciate that, in some examples, the functionality of the devices and / or methods and / or processes described herein can 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 functionality of the devices and / or methods and / or processes described herein can be implemented using a computing device that can access a code memory (not shown) that stores computer-readable program code for the operation of the computing device. The computer-readable program code can be stored on a computer-readable storage medium that is fixed, tangible, and directly readable by these components (e.g., removable disk, CD-ROM, ROM, fixed disk, USB drive). In addition, it can be understood that the computer-readable program can be stored as a computer program product that includes a computer-usable medium. In addition, a persistent storage device can include computer-readable program code. It should also be understood that the computer-readable program code and / or the computer-usable medium can include non-transitory computer-readable program code and / or non-transitory computer-usable medium. Alternatively, the computer-readable program code can be stored remotely, but can be transmitted to these components via a modem or other interface device connected to a network (including but not limited to the Internet) through a transmission medium. The transmission medium can be 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 optics, or other transmission schemes) or a combination thereof.

[0145] Those skilled in the art will understand that there are still more alternative examples and possible modifications, and the above examples are only illustrative of one or more examples. Therefore, the scope of the present invention is defined only by the appended claims.

Claims

1. A method implemented at a projector, the projector comprising a light modulator and a controller, the controller communicatively coupled to: an image source, the image source configured to perform one or more of providing an image frame and receiving an image frame to drive the light modulator; and at least one light source arranged to illuminate the light modulator according to one or more colors, the method comprising the steps of: determining, via the controller, a margin for a highest brightness pixel of the given image frame, the margin representing a difference between a peak brightness associated with a peak throughput of the light modulator and a corresponding peak brightness associated with the highest brightness pixel; controlling, via the controller, a light source brightness of the at least one light source to a reduced light source brightness corresponding to a peak light source brightness reduced by the margin; controlling, via the controller, a highest brightness region of the light modulator to the peak throughput corresponding to the highest brightness pixel of the given image frame; and Based on the reduced light source brightness, the controller controls the lowest brightness region of the light modulator to a corresponding low brightness throughput corresponding to the lowest brightness pixel of the given image frame, and the low brightness throughput maintains a substantially constant given low brightness output by the lowest brightness region of the light modulator across the image frame.

2. The method according to claim 1, wherein: The substantially constant given low brightness includes a residual brightness of the light modulator that is in an off state when the light source brightness is at the reduced light source brightness plus a corresponding brightness determined to bring the lowest brightness area to the substantially constant given low brightness.

3. The method according to claim 1, when the reduced light source brightness changes from image frame to image frame due to the change of the margin, the method further comprises the following steps: Corresponding to the lowest brightness pixel of the given image frame, the corresponding low brightness throughput is changed to maintain the substantially constant given low brightness of the lowest brightness area of ​​the light modulator.

4. The method according to claim 1, further comprising the following steps for intermediate brightness pixels corresponding to corresponding intermediate brightnesses between the lowest brightness associated with the lowest brightness pixel and the highest brightness associated with the highest brightness pixel of the given image frame: Based on the value of the reduced light source brightness of the at least one light source, the corresponding throughput of the intermediate brightness region of the light modulator is controlled to a corresponding intermediate brightness throughput corresponding to the intermediate brightness pixel of the given image frame, and the intermediate brightness throughput maintains a substantially constant corresponding given brightness output by the intermediate brightness region of the light modulator across the image frame.

5. The method according to claim 1, further comprising the steps of: As a function of the corresponding brightness associated with the intermediate brightness pixels, the corresponding throughput of the intermediate brightness pixels of the given image frame is controlled to a corresponding intermediate brightness throughput between the low brightness throughput and the peak throughput.

6. The method according to claim 1, further comprising the steps of: As a function of the corresponding brightness associated with the intermediate brightness pixels, the corresponding throughput of the given image frame is linearly controlled to a corresponding intermediate brightness throughput between the low brightness throughput and the peak throughput.

7. The method according to claim 1, wherein: The at least one light source includes a red laser, a green laser and a blue laser, wherein the corresponding margin of each of the red laser, the green laser and the blue laser is determined, wherein each of the red laser, the green laser and the blue laser is controlled according to a corresponding margin of each of the red laser, the green laser and the blue laser, and For each color among red, green and blue, the corresponding throughput of the corresponding highest brightness pixel and the corresponding lowest brightness pixel is controlled according to the corresponding margin of each laser among the red laser, the green laser and the blue laser.

8. The method according to claim 1, wherein: The optical modulator includes a digital micromirror device (DMD).

9. The method according to claim 1, wherein: The corresponding maximum brightness associated with the maximum brightness pixel is less than the peak brightness.

10. The method according to claim 1, wherein: The lowest brightness pixel of the given image frame corresponds to a black pixel.

11. A projector, comprising: Light modulator; as well as a controller communicatively coupled to: an image source configured to perform one or more of providing an image frame and receiving an image frame to drive the light modulator; and at least one light source arranged to illuminate the light modulator according to one or more colors, The controller is configured to, for a given one of the image frames and a given one of the one or more colors: determining a margin for a highest brightness pixel of the given image frame, the margin representing a difference between a peak brightness associated with a peak throughput of the light modulator and a corresponding highest brightness associated with the highest brightness pixel; controlling the light source brightness of the at least one light source to a reduced light source brightness corresponding to a peak light source brightness reduced by the margin; corresponding to the highest brightness pixel of the given image frame, controlling the highest brightness region of the light modulator to the peak throughput; as well as Based on the reduced light source brightness, the lowest brightness region of the light modulator is controlled to a corresponding low brightness throughput corresponding to the lowest brightness pixel of the given image frame, and the low brightness throughput maintains a substantially constant given low brightness output by the lowest brightness region of the light modulator across the image frame.

12. The projector according to claim 11, wherein: The substantially constant given low brightness includes a residual brightness of the light modulator that is in an off state when the light source brightness is at the reduced light source brightness plus a corresponding brightness determined to bring the lowest brightness area to the substantially constant given low brightness.

13. The projector according to claim 11, wherein: When the reduced light source brightness changes from image frame to image frame due to the change of the margin, the controller is further configured to: Corresponding to the lowest brightness pixel of the given image frame, the corresponding low brightness throughput is changed to maintain the substantially constant given low brightness of the lowest brightness area of ​​the light modulator.

14. The projector according to claim 11, wherein: The controller is also configured to: For the given image frame, a middle-brightness pixel corresponding to a corresponding middle-brightness between a lowest brightness associated with the lowest-brightness pixel and a highest brightness associated with the highest-brightness pixel: Based on the value of the reduced light source brightness of the at least one light source, the corresponding throughput of the intermediate brightness region of the light modulator is controlled to a corresponding intermediate brightness throughput corresponding to the intermediate brightness pixel of the given image frame, and the intermediate brightness throughput maintains a substantially constant corresponding given brightness output by the intermediate brightness region of the light modulator across the image frame.

15. The projector according to claim 11, wherein: The controller is also configured to: As a function of the corresponding brightness associated with the intermediate brightness pixels, the corresponding throughput of the intermediate brightness pixels of the given image frame is controlled to a corresponding intermediate brightness throughput between the low brightness throughput and the peak throughput.

16. The projector according to claim 11, wherein: The controller is also configured to: As a function of the corresponding brightness associated with the intermediate brightness pixels, the corresponding throughput of the given image frame is linearly controlled to a corresponding intermediate brightness throughput between the low brightness throughput and the peak throughput.

17. The projector according to claim 11, wherein: The at least one light source includes a red laser, a green laser and a blue laser, wherein the corresponding margin of each of the red laser, the green laser and the blue laser is determined, wherein each of the red laser, the green laser and the blue laser is controlled according to the corresponding margin of each of the red laser, the green laser and the blue laser, and For each color among red, green and blue, the corresponding throughput of the corresponding highest brightness pixel and the corresponding lowest brightness pixel is controlled according to the corresponding margin of each laser among the red laser, the green laser and the blue laser.

18. The projector according to claim 11, wherein: The optical modulator includes a digital micromirror device (DMD).

19. The projector according to claim 11, wherein: The corresponding maximum brightness associated with the maximum brightness pixel is less than the peak brightness.

20. The projector according to claim 11, wherein: The lowest brightness pixel of the given image frame corresponds to a black pixel.

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