Quantum dots and photoluminescent color filters

Abstract

Image data for rendering an image to a viewer on an image display is received. The image data defines, for a pixel of the image display, a pixel value of the image to be rendered. The pixel value for the pixel includes a plurality of component pixel values ​​corresponding to a plurality of color components of a color space. A gamut location value for the pixel value is calculated based on two or more of the component pixel values ​​of the plurality of component pixel values ​​of the pixel value defined for the pixel. The gamut location value is used to determine whether to apply bandwidth expansion to an image rendering light generated by the pixel of the image display to render the pixel value. The image rendering light is directed to the viewer.

Description

[Technical field]

[0001] This application claims priority to U.S. Provisional Application No. 63 / 305,632, filed February 1, 2022, and European Application No. 22156126.9, filed February 10, 2022, all of which are incorporated herein by reference in their entirety.

[0002] The present invention relates generally to display technology, and more particularly to display technology using light regenerating materials. [Background technology]

[0003] Color filter arrays in image displays are generally produced by photolithography or printing techniques. These color filters typically consist of red, green, and blue filters patterned onto pixel arrays, allowing pixel elements to modulate light by color in addition to intensity. In operation, a pixel element can vary the intensity of the light that passes through it. The intensity-modulated light of each pixel element can be further color filtered by an overlying color filter. Much light is wasted by color filtering and converted into harmful heat that can reduce the performance and lifespan of the image display.

[0004] Thus, engineering a display system having a relatively wide color gamut and a relatively high peak brightness has become a difficult and costly endeavor by many display manufacturers because of the need to integrate relatively expensive optical, electronic, and mechanical components into the image display device.

[0005] The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Thus, unless otherwise indicated, it should not be assumed that any of the approaches described in this section constitute prior art by virtue of their inclusion in this section. Similarly, it should not be assumed that problems identified with one or more approaches have been recognized in the prior art based on this section, unless otherwise indicated. [Brief description of the drawings]

[0006] The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like elements are referred to with like reference numerals, including the following figures: [Figure 1] 1 illustrates an example of a display system. [Figure 2A] 2A-2E show examples of multi-layer configurations of unit structures in an image display. [Figure 2B] 2A-2E show examples of multi-layer configurations of unit structures in an image display. [Figure 2C] 2A-2E show examples of multi-layer configurations of unit structures in an image display. [Figure 2D] 2A-2E show examples of multi-layer configurations of unit structures in an image display. [Figure 2E] 2A-2E show examples of multi-layer configurations of unit structures in an image display. [Figure 2F] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 2G] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 2H] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 2I] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 2J] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 2K] 2F-2K show examples of pixels each having multiple sub-pixels. [Figure 3A] 3A and 3B show examples of the spectral power distribution (SPD) of narrowband light and broadband light. [Figure 3B] 3A and 3B show examples of the spectral power distribution (SPD) of narrowband light and broadband light. [Figure 3C] 3C-3E show examples of color gamuts. [Figure 3D] 3C-3E show examples of color gamuts. [Figure 3E] 3C-3E show examples of color gamuts. [Figure 4] 1 shows an example of a process flow. [Diagram 5] 1 illustrates an example of a hardware platform on which a computer or computing device described herein may be implemented. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Possible example embodiments of quantum dots and photoluminescent color filters are described herein. In the following description, for the purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent that the present invention can be practiced without these specific details. Additionally, well-known structures and devices are not described in exhaustive detail in order to avoid unnecessarily obscuring, obscuring, or confusing the present invention.

[0008] Example embodiments will now be described according to the following outline: 1. Overview 2. Structure Overview 3. Unit Structure 4. In-cell polarizer 5. Spectral power distribution of reconstructed light 6. Preventing or reducing metamerism problems 7. Saturation / position-based wavelength expansion 8. Process Flow Example 9. Computer System Implementation Examples 10. Equivalence, extension, substitution, and miscellaneous

[0009] 1. Overview This overview provides a basic description of some aspects of possible embodiments of the present invention. However, this overview is not an extensive or exhaustive summary of the aspects of the possible embodiments. It should also be noted that this overview is not intended to identify particularly key aspects or elements of the possible embodiments, to delimit the scope of the particular possible embodiments, or to be understood as a general invention. It should be understood that this overview is merely intended to present some concepts related to the example embodiments in a summary and simplified form, and is merely a conceptual premise for the more detailed description of the example embodiments that follows.

[0010] In a display system, the light that renders an image to a viewer travels through numerous optical layers, modules, structures, components, etc. from the light source to the viewer and constitutes only a portion of the total light output from the light source. A significant portion of the total light output does not reach the viewer for a variety of reasons. In one example, if a pixel represents a red pixel value in a rendered image, non-red light is rejected or absorbed for that pixel. In another example, if a pixel represents a relatively dark pixel value in a rendered image, much of the light that is incident on a light modulating layer, such as a liquid crystal cell, for that pixel cannot be transmitted through the light modulating layer because the liquid crystal cell is set to a relatively less transparent state based on the relatively dark pixel value.

[0011] The color filters or other optical layers in the image display described herein can include light recycling materials to increase light efficiency. The light recycling materials can be stimulated by the light from the light source and the recycled light. The light of shorter wavelengths, such as UV or blue light, can be converted by the light recycling materials into light of longer wavelengths, such as blue, green, or red light, to reach the viewer.

[0012] Examples of light regenerating materials in image displays are described in U.S. Provisional Application No. 61 / 486,160, entitled "TECHNIQUES FOR QUANTUM DOTS," filed May 13, 2011, U.S. Provisional Application No. 61 / 486,166, entitled "TECHNIQUES FOR QUANTUM DOT ILLUMINATIONS," filed May 13, 2011, and U.S. Provisional Application No. 61 / 486,171, entitled "QUANTUM DOT FOR DISPLAY PANELS," filed May 13, 2011, the contents of which are hereby incorporated by reference for all purposes as if fully set forth herein.

[0013] The techniques described herein may be implemented in image displays to use light regenerating materials in color filters and / or other optical layers to generate additional image rendering light that can be used to support a relatively high dynamic range, a relatively wide color gamut, and relatively saturated colors in image rendering operations.

[0014] Additionally, optionally or alternatively, the spectral power distribution (SPD) of the image rendering light from the light source and the regenerated light from the light regenerating material can be controlled or adjusted for each pixel or each pixel block based on the pixel value, saturation, etc. represented by the pixel or pixel block. For example, to prevent or reduce metamerism defects, a color represented by a pixel can be rendered with image rendering light of a specific SPD that is individually controlled or adjusted for that pixel or the pixel block that contains that pixel. The SPD can have a relatively narrow band of primary colors when the color represented is not susceptible to metamerism defects. Conversely, the SPD can have a broadened or wide band of color light when the color represented is (considered or determined to be) susceptible to metamerism defects.

[0015] Example embodiments described herein relate to an image rendering operation using an image display. Image data for rendering an image to a viewer on an image display is received. The image data defines pixel values ​​of the image to be rendered for pixels of the image display. The pixel values ​​for the pixels include a plurality of component pixel values ​​corresponding to a plurality of color components of a color space. A color gamut locational value for the pixel value is calculated based on two or more of the component pixel values ​​of the pixel value defined for the pixel. The color gamut locational value is used to determine whether bandwidth expansion should be applied to an image rendering light generated by a pixel of the image display to render the pixel value. The image rendering light is directed to the viewer.

[0016] In some embodiments, the method comprises providing a display system as described herein. In some possible embodiments, the mechanisms described herein form part of a display system including, but not limited to, handheld devices, tablet computers, theater systems, outdoor displays, gaming consoles, televisions, laptop computers, netbook computers, cellular wireless telephones, e-book readers, point of sale terminals, desktop computers, computer workstations, computer kiosks, PDAs, and various other types of terminals and display units.

[0017] Various modifications to the preferred embodiments and generic principles and features described herein will be readily apparent to those skilled in the art, and thus the present disclosure is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features described herein.

[0018] 2. Structure Overview 1 illustrates an example of a display system 100 having an image display 102 or operating in conjunction with an image display 110. The display system (100) includes display logic 104 that implements light source control logic 106 and (in addition, or alternatively, optionally) light valve control logic 108.

[0019] The image display (102) has an array of pixels (one of which is 112) arranged in a spatial pattern (e.g., two-dimensional, curved, flat, regularly shaped, irregularly shaped, etc.). Each pixel (e.g., 112) of the image display (102) may be composed of multiple sub-pixels (one of which is 114).

[0020] The light source control logic (106) controls and / or monitors the operation of one or more light sources (e.g., backlight units, sidelight units, arrays of light emitting diodes or LEDs each illuminating multiple pixels or multiple sub-pixels, arrays of micro LEDs each illuminating a single pixel or a single sub-pixel, etc.) that emit light to illuminate some or all sub-pixels of pixels in an array of pixels of the image display (102).

[0021] The light valve control logic (108) controls and / or monitors the operation of the light valves at the sub-pixels of pixels in the array of pixels of the image display (102).

[0022] The display logic (104) may be operatively coupled to an image data source 110 (e.g., a set-top box, a network server, a storage medium, or the like) and may receive image data from the image data source (110). The image data may be received by the display logic (104) from the image data source (110) in a variety of ways, including, but not limited to, one or more of the following: over-the-air broadcast, a High-Definition Multimedia Interface (HDMI®) data link, a wired or wireless network / data connection, a media / storage device, a set-top box, a media streaming server, a storage medium, or the like.

[0023] In some operating scenarios, images / frames decoded or derived from image data may be used by light source control logic 106 to drive or control light sources in an image display. The light source control logic 106 may use pixel values ​​to derive specific digital (light) control or drive values ​​that may be used by the light source control logic 106 (e.g., having light source control circuitry, etc.) to drive or control specific intensities for illuminating a single pixel or a single sub-pixel on a pixel-by-pixel, sub-pixel-by-sub-pixel block, sub-pixel group, etc. In one example, the light source control logic 106 may use a group value or averaged / sub-sampled / down-sampled values ​​of all pixel values ​​in a spatial region (e.g., adjacent, contiguous, etc.) having a group of pixels (e.g., adjacent, contiguous, etc.) to derive specific digital control or drive values ​​for illuminating the spatial region (e.g., only). In another example, the light source control logic (106) may use some or all of the individual sub-pixel values ​​(e.g., corresponding to different color components / channels of a color space such as RGB, YCbCr, ICtCp, IPT, etc.) in a single pixel or a single sub-pixel to derive a particular digital control or drive value for illuminating the single pixel or the single sub-pixel (e.g., only).

[0024] In some operating scenarios, images / frames decoded or derived from the image data may be used by light valve control logic 108 to drive or control light valves in an image display. The light valve control logic 108 may use pixel or sub-pixel values ​​to derive specific digital (valve) control or drive values ​​that may then be used by the light valve control logic (e.g., having column and / or row drive circuits, etc.) to drive or control a specific transmittance (for light transmission) of a pixel, sub-pixel, pixel block, sub-pixel group, etc. In one example, the light valve control logic 108 may use a group value or an averaged, subsampled, and / or downsampled value of all pixel values ​​in a spatial region (e.g., adjacent, contiguous, etc.) having a group of pixels (e.g., adjacent, contiguous, etc.) to set a specific transmittance for that spatial region (e.g., only). In another example, the light valve control logic (108) can use some or all of the individual subpixel values ​​(e.g., corresponding to different color components / channels of a color space such as RGB, YCbCr, ICtCp, IPT, etc.) in a single pixel or a single subpixel to derive a particular transmittance for the single pixel or for (e.g., only) the single subpixel.

[0025] In some operating scenarios, a unit structure in the image display (102), such as a pixel (e.g., 112) or a sub-pixel therein (e.g., 114), may have a per-pixel or per-sub-pixel light source (e.g., designated to illuminate only that pixel or that sub-pixel therein).

[0026] In one example, the unitary structures do not have light valves whose transmittance is controlled based on image data rendered on the image display (102). Rather, the illumination of a pixel or subpixel (represented by the unitary structure), i.e., the brightness / luminance perceived by a viewer of the image display (102), can be directly controlled by the light source control logic (106) using digital control or drive values ​​generated based on the image data portion specified for the pixel or subpixel. In this example, each subpixel in the image display (102) can have a per-subpixel light source whose emission is adjusted by the light source control logic (106) to generate (transmitted) light that is directed towards a viewer (not shown, in front of the image display (102)) of the image rendered on the image display (102). The operation of the light source control logic (106) causes an image / frame to be rendered by the array of pixels of the image display (102) at a spatial resolution supported by the image data received from the image data source (110) and supported by the image display (102). The light valve control logic (108) may optionally be omitted from the display logic (104) in this example.

[0027] In another example, the unitary structures do not have a light source whose intensity / luminance is controlled based on image data rendered on the image display (102). Rather, each subpixel or pixel in some or all of the subpixels or pixels of the image display (102) may be illuminated with (e.g., constant) light originating from a light source whose luminance is not adjusted based on the image data or a downsampled / subsampled version thereof. The brightness / luminance of the pixel or subpixel (represented by the unitary structure) as perceived by a viewer of the image display (102) may be directly controlled by the light valve control logic (108) using a digital control or drive value generated based on the image data portion specified for the pixel or subpixel. In this example, each subpixel in the image display (102) may have a per-subpixel light valve whose light transmittance is adjusted by the light valve control logic (108) to pass (transmit) light directed toward the viewer of the image rendered on the image display (102). The operation of the light valve control logic 108 causes an image / frame to be rendered by the array of pixels of the image display 102 at a spatial resolution supported by received image data from the image data source 110 and supported by the image display 102. The light source control logic 106 may be optionally omitted from the display logic 104 in this example.

[0028] In yet another example, the elemental structure has both a light source whose intensity / luminance is controlled based on image data to be rendered on the image display (102) and a light valve whose transmittance is controlled based on image data to be rendered on the image display (102). Each sub-pixel or pixel in some or all of the sub-pixels or pixels of the image display (102) may be illuminated with (e.g., variable) light from a light source whose luminance is adjusted (e.g., individually controlled per pixel, per sub-pixel, per pixel block, per sub-pixel block, etc.) based on the image data or a downsampled / subsampled version thereof. In addition, the transmittance of a light valve within each sub-pixel or pixel in some or all of the sub-pixels or pixels of the image display (102) may be adjusted (e.g., individually controlled per pixel, per sub-pixel, per pixel block, per sub-pixel block, etc.) based on the image data or a downsampled / subsampled version thereof. Thus, in this example, the brightness / luminance of a pixel or sub-pixel (represented by a unit structure) as perceived by a viewer of the image display (102) can be collectively controlled by both the light source control logic (106) and the light valve control logic (108) with respective digital control or drive values, each generated based on the image data portion specified for the pixel or sub-pixel. The combined operation of the light source control logic (106) and the light valve control logic (108) causes an image / frame to be rendered by the array of pixels of the image display (102) at a spatial resolution supported by the received image data from the image data source (110) and supported by the image display (102). In this example, in various operating scenarios, the spatial resolution supported by the light source control logic (106) may be the same as, lower than, or higher than the spatial resolution supported by the light valve control logic (108).The highest spatial resolution supported by the image display (102) may correspond to the highest spatial resolution within a set of spatial resolutions that represent the union of the spatial resolution(s) supported by the light source control logic (106) and the spatial resolution(s) supported by the light valve control logic (108).

[0029] 3. Unit Structure Unitary structures, such as pixel / sub-pixel structures, may be implemented in one or more layers within an image display (102) of a display system (100) such as that shown in Figure 1. Some or all of these layers may be used to control or adjust the individual intensities and individual colors of light directed to a viewer at a spatial resolution and / or image refresh rate supported by the display system (100) or the image display (102) therein.

[0030] 2A shows a multi-layer configuration of a first example unit structure 200-1 (sometimes also referred to as a cell) representing a pixel or sub-pixel therein of an image display (e.g., 102 in FIG. 1). The unit structure (200-1) has a backlight unit (BLU) layer portion (referred to as BLU 212) that emits a backlight portion designated to illuminate other layer portions of the unit structure (200-1). These other layer portions of the unit structure (200-1) may include some or all of, but are not limited to, an optical stack layer portion (referred to as optical stack 210), a light valve layer portion (referred to as liquid crystal or LC 208), a polarizer layer portion within the unit structure (referred to as in-cell polarizer 206), a light recycling color filter layer portion (referred to as quantum dot or QD color filter 204), and a (non-light recycling) color filter layer portion (referred to as color filter 202).

[0031] It should be noted that the multi-layer configuration of FIG. 2A is for illustrative purposes only. In various embodiments, the unit structures described herein may include more or less layer portions than those shown. In addition, optionally or alternatively, different types of layer portions can be incorporated into the unit structures described herein in addition to or in place of some or all of the layer portions shown in FIG. 2A. For example, in addition to or in place of the BLU (110), a side-emitting light unit portion can be incorporated or used with a light guide that directs or guides the side-emitting light generated and received from the side-emitting light unit to illuminate the remaining portions of the unit structures described herein.

[0032] The layer portions within unit structure (200-1) may or may not be part of a uniform or homogeneous layer (eg, continuous, uninterrupted, etc.).

[0033] In one example, the color filter (202) in the unit structure (200-1) and other color filters on other unit structures of the image display (102) of Figure 1 may be of the same type and collectively form (e.g., coated or disposed on a substrate glass) a uniform or homogeneous finish color filter layer over the (non-uniform or inhomogeneous) light-reproducing color filter layer of which the QD color filter (204) is a part. In this example, the color filter (202) may be a multi-band color filter that allows for the passage of a combination of colors in multiple light wavelength bands represented by image-rendering light from different sub-pixels of different colors or different color compositions in the image display (102). The color filter (202) can be used to prevent or reduce the possibility that an ambient light portion 216 incident on the unit structure (200-1) will excite the QD color filter to regenerate a regenerated light portion that is dependent on the ambient light portion (216) (its intensity and composition) (e.g., as part of the image rendering light portion 214), thereby causing the image rendering light portion (214) directed from the unit structure (200-1) to the viewer to be inaccurate in terms of color accuracy, saturation, and / or dynamic range.

[0034] In another example, the color filters (202) in the unit structure (200-1) and other color filters on other unit structures of the image display (102) of Figure 1 may be of different types and collectively form a non-uniform or inhomogeneous color filter layer. The color filters (202) may be single-band or multi-band color filters that allow for the passage of a combination of one or more colored light wavelength bands emitted from or directed to the QD color filters (204) that they cover. Compared to the previous example, the color filter (202) in this example can be used more effectively to prevent or reduce the possibility that the ambient light portion (216) incident on the unit structure (200-1) will excite the QD color filter to regenerate a regenerated light portion that is dependent on the ambient light portion (216) (intensity and composition) (e.g., as part of the image rendering light portion 214), thereby causing the image rendering light portion (214) directed from the unit structure (200-1) to the viewer to be inaccurate in terms of color accuracy, saturation, and / or dynamic range.

[0035] The QD color filters (204) may be part of a light regenerating color filter layer comprised of a 2D pattern / array of light regenerating color filters on or within a corresponding 2D pattern / array of elemental features that can impart different colors to the image rendering light (a portion of which is 214 in FIG. 2A) that is directed to the viewer. Similarly, the LC (208) may be part of a light valve layer (also referred to as a "light modulating layer") comprised of a 2D pattern / array of light valves on or within a corresponding 2D pattern / array of elemental features that are controlled by distinct electrodes driven by the light valve control logic (108) of FIG.

[0036] Each layer portion within some or all of the layer portions of the unit structures, such as BLU 110, LC 106 in FIG. 2A, can be actively controlled (e.g., using electronic / light pulses / signals generated by electronic or optical components such as light source and / or light valve control circuits) based at least in part on image data portions that define the image portions to be rendered by the unit structures.

[0037] 2B shows a multi-layer configuration of a second example element structure 200-2 representing a pixel or sub-pixel therein of an image display (such as 102 in FIG. 1). The element structure (200-2) has a backlight unit (BLU) layer portion (such as BLU (212)) that emits a backlight portion designated to illuminate other layer portions of the element structure (200-3). These other layer portions of the unit structure (200-2) may include some or all of, but are not necessarily limited to, an optical stack layer portion (e.g., optical stack (210)), a first light valve layer portion (referred to as LC208-1), an optical diffuser layer portion (referred to as diffuser 218), a second light valve layer portion (referred to as LC208-2), a polarizer layer portion within the unit structure (e.g., in-cell polarizer (206)), a light regenerating color filter layer portion (e.g., QD color filter (204)), and a color filter layer portion (e.g., color filter (202)).

[0038] The elemental structure (200-2) incorporates or uses multiple light valve (or light modulating) layers. These light valves can be used to increase the overall dynamic range of the image display (102). For example, if each light valve layer supports 256 different dynamic range levels, the combination or incorporation of two light valve layers can potentially support dynamic range levels up to 256x256, thereby greatly increasing the availability of contrast levels in the overall dynamic range of the image display (102). In addition to increasing the total number of representable brightness levels, an image display with multiple light valve layers can employ, incorporate or use brighter light sources to increase peak brightness, compared to an image display with a single light valve layer. Furthermore, an image display with multiple light valve layers can achieve darker black levels, compared to an image display with a single light valve layer.

[0039] Since both light valve layers may have regular patterns, visual artifacts such as moiré patterns may be prone to occur. An optical diffuser layer, of which the diffuser 218 is a part, may be incorporated or disposed between the first light valve layer, of which the LC-1 (208-1) is a part, and the second light valve layer, of which the LC-2 (208-2) is a part. By incorporating an optical diffuser layer, such as a holographic or non-holographic optical diffuser, into the image display (102), the light transmitted through the first light valve layer towards the second light valve layer may be diffused to prevent or greatly reduce moiré patterns.

[0040] FIG. 2C shows a multi-layer configuration of a third example unit structure 200-3 representing a pixel or subpixel therein of an image display (e.g., 102 in FIG. 1). The unit structure (200-3) has a backlight unit (BLU) layer portion (e.g., BLU (212) or the like) that emits a backlight portion designated to illuminate one or more other layer portions of the unit structure (200-3). In some embodiments, the backlight portion can illuminate a light regenerating color filter layer portion (e.g., QD color filter (204) or the like) without passing through any light valve (or light modulation) layer. The intensity and / or color of the backlight portion illuminating the QD color filter (204) can be directly adjusted by light source control logic (e.g., 106 in FIG. 1) based on image data or a portion thereof.

[0041] For illustrative purposes only, it is described that the light valve layer in the unitary structures as shown in Figures 2A and 2B may be implemented as a liquid crystal layer. It should be noted that in various embodiments, either LC-based or non-LC-based light valve (or light modulating) layers may be incorporated into the unitary structures of image displays as described herein.

[0042] For the sake of illustration only, it is stated that a (non-light-reproducing) color filter layer in the unit structure as shown in Figures 2A and 2B can be incorporated to prevent or reduce ambient light-induced reproduction light. It should be noted that in various embodiments, such a color filter layer may or may not be incorporated in the unit structure of the image display as described herein. For example, as shown in Figure 2E, a finish polarizer layer (referred to as finish polarizer 220) with its finish polarizer layer portion coated on the top surface of a uniform or homogeneous substrate (a portion of which is the substrate portion (referred to as glass 222)) can be used instead of or in addition to a color filter layer.

[0043] In the rendering operation of the image display (102), the finish polarizer polarizes the ambient light incident on the substrate layer into a specific linear or circular polarization state. The ambient incident light is then reflected by the substrate into reflected light with a polarization state orthogonal to the specific linear or circular polarization state. The reflected light in the orthogonal state is absorbed, rejected, or otherwise filtered out by the finish polarizer, thereby preventing the reflected light from mixing with or becoming part of the image rendering light and reaching the viewer. Some ambient light may still reach the QD color filter (204), causing the QD color filter (204) to reproduce ambient light induced light with different polarization states, including the specific linear or circular polarization state, which may pass through the finish polarizer (220) toward the viewer.

[0044] In comparison, in an image rendering operation of an image display (102) implementing the unit structure of FIG. 2A or FIG. 2B, the color filter layer can filter out more ambient light, and therefore the QD color filter (204) is less likely to cause the reproduction of ambient light induced light that may pass through the finish polarizer (220) toward the viewer.

[0045] 4. In-cell polarizer The unitary structures in the image display (102) may include layer portions (one or more) that may be designed to transmit, reflect, absorb, and / or recycle light of a particular polarization state in an image-rendering operation. For example, a light valve layer portion such as that shown in Figure 2A, 2B, or 2E may be implemented with a particular optical axis and designed to transmit light of a first polarization state and reject light of a second polarization state that is orthogonal to the first polarization state when the electrodes used to control the light valve layer portion are in a fully on state having the highest transmittance in an image-rendering operation.

[0046] The light regenerating layer portion, such as a QD color filter within the unit structure, can regenerate light of different polarization states, some of which can be transmitted through the light valve layer portion while other parts can be reflected by the light valve layer portion.

[0047] In some embodiments, an in-cell polarizer may be disposed between the QD color filter and the light valve layer portion to reflect the reconstructed light of the first polarization state reconstructed by the QD color filter toward the viewer in order to redirect light relatively effectively toward the viewer. Also, the reconstructed light of the second polarization state reconstructed by the QD color filter may be reflected toward the viewer by the light valve layer portion. As a result, the unit structure in this example may support or achieve a relatively higher dynamic range than a unit structure that does not implement the technology described herein. Additionally, optionally or alternatively, a reflection promotion layer portion (or film) that transmits the second polarization state and reflects the first polarization state may be used in addition to or instead of the in-cell polarizer.

[0048] 5. Spectral power distribution of reconstructed light A light regenerating layer, such as a layer of QD color filters, in the spatial array / pattern of pixels of the image display (102) can be composed of a light regenerating material that is excited by injected light (e.g., blue light, ultraviolet or UV light, narrow-band injected light from a light source(s), etc.) to regenerate light of different wavelengths. The light regenerating material can be selected to regenerate light of a narrow (wavelength) band, a wide (wavelength) band, etc., of primary colors (e.g., red, green, and blue in the RGB color system) from the injected light received by the light regenerating material.

[0049] Narrow bands of different colors of light may be measured or specified in different wavelength ranges or subranges in nanometers. Examples of narrow band colors (e.g., representing primary colors, representing non-primary colors, etc.) of light may include, but are not limited to, blue or near blue light in a wavelength band of 5-20 nanometers or less, green or near green light in a wavelength band of 5-30 nanometers or less, red or near red light in a wavelength band of 5-40 nanometers or less, etc. As used herein, the terms "broadband", "widened band", or "wider band" may refer to a wavelength band that is wider (e.g., 25%, 50%, 75%, 100%, or more) than a narrow band. In one example, a broad band of blue light may be measured or specified in a wavelength range that is larger (e.g., 25%, 50%, 75%, 100%, or more) than a wavelength range or narrow band of blue light. In another example, a broadband for green light may be measured or specified as a wavelength range that is greater (e.g., 25%, 50%, 75%, 100% or more) than the wavelength range or narrow band for green light. In another example, a broadband for red light may be measured or specified as a wavelength range that is greater (e.g., 25%, 50%, 75%, 100% or more) than the wavelength range or narrow band for red light. As used herein, the term "broadband" may refer to the entire visible light spectrum (or 80%, 90%, or more).

[0050] The regenerated light of a first wavelength (or wavelength band) can be regenerated by a specific light regenerating material (e.g., a specific QD type, a specific luminescent material type, etc.) excited by injected light of a second wavelength (or wavelength band) that is higher than the first wavelength (or wavelength band).

[0051] In an image rendering operation, the optical spectral power distribution (or SPD) of the regenerated light directed to a viewer by a unit structure or group of unit structures described herein, i.e., the distribution of light intensity across wavelengths or wavelength ranges in the entire visible light wavelength spectrum, can be specifically tuned based on the pre-configured light regenerating material type within the light regenerating portion of the unit structure and the optical spectral power distribution (e.g., real-time, run-time, dynamically tunable / controllable, etc.) of the injected light.

[0052] By selecting a specific type of light regenerating material to be manufactured in the unit structure or group of unit structures (e.g., spatially adjacent, belonging to the same pixel, belonging to two spatially adjacent pixels, etc.), by controlling the light source that generates the light of a specific power distribution injected into the light regenerating material based at least in part on the image data, and / or by controlling the transmittance of the light valve layer (one or more), the unit structure or group of unit structures can direct the regenerated light of a specific light spectral power distribution to the viewer during the image rendering operation. In one example, the unit structure or group of unit structures may include multiple different types of light regenerating materials. Some of these types of light regenerating materials may reproduce primary colors in a relatively narrow band (e.g., 10, 20, or 30 nanometers, etc.). Other types of light regenerating materials may reproduce primary colors in a wider band (e.g., 30 nanometers, 40 nanometers, 50 nanometers, or more, etc.). Additionally, optionally or alternatively, some other of these types of light regenerating materials may regenerate narrow or broad bands of non-primary colors, which may be adjacent wavelengths (or wavelength bands) next to the wavelengths (or wavelength bands) of the primary colors.

[0053] In some embodiments, some or all of the different types of light regenerating materials may be excited or stimulated to regenerate light using injection light (e.g., narrow band or broad band, etc.) emitted by the same type of light source. In some embodiments, some or all of the different types of light regenerating materials may be excited or stimulated to regenerate light using injection light (e.g., narrow band or broad band, different narrow band or broad band, etc.) emitted by different types of light sources.

[0054] In an image rendering operation, in response to determining that a narrowband primary color should be generated or reproduced at a particular (light) intensity, the light source can be controlled to emit light of a particular intensity and a particular wavelength (or wavelength band) that excites or stimulates a particular type of light reproduction material to generate the narrowband primary color having the particular intensity.

[0055] Additionally, optionally or alternatively, in response to determining that a broader band of primary colors should be generated or reproduced at a particular (light) intensity, the light source can be controlled to emit light of a particular intensity and a particular wavelength (or wavelength band) that excites or stimulates a particular type of light reproduction material to generate the broader band of primary colors having the particular intensity.

[0056] Additionally, optionally or alternatively, in response to determining that narrow or broadband non-primary colors should be generated or reproduced at a particular (light) intensity, the light source can be controlled to emit light of a particular intensity and a particular wavelength (or wavelength band) that excites or stimulates a particular type of light reproduction material to generate narrow or broadband primary colors having a particular intensity.

[0057] It should be noted that light of different wavelengths (or wavelength bands) may be generated or reproduced by unit structures or groups of unit structures in a time-sequential, simultaneous, or partially time-sequential and partially simultaneous manner.

[0058] 6. Preventing or reducing metamerism problems Narrowband colors rendered by a unit structure or group of unit structures, such as a 10 nanometer blue primary, a 20 nanometer green primary, a 30 nanometer red primary, etc., may be perceived differently by different viewers due to possible metamerism defects due to differences in color vision between viewers. For example, an Asian woman may perceptually look or visually perceive a narrowband red (rendered by narrowband red light) differently than a non-Asian woman. Different viewers may perceptually look or visually perceive a narrowband white, for example, rendered with a set of narrowband primaries, differently. Some viewers may even see or visually perceive narrowband white as pink instead of white.

[0059] The techniques described herein can be implemented to prevent or reduce metamerism defects, thereby allowing different viewers in a viewer population to see or visually perceive colors with the same consistent color perception or with no or little perceptual difference. These techniques can be used to render a red primary color with a particular SPD that allows both Asian and non-Asian women to perceive the rendered color as the same red. Similarly, these techniques can be used to render a white color with a particular SPD that allows all or substantially all (e.g., 99%) viewers in a viewer population to perceive the rendered color as the same white.

[0060] In some operational scenarios, a particular SPD with which a particular color is rendered may have a particular mix or stack of light of different wavelength bands, such as a mix or stack of different narrow bands and / or broad bands. A particular mix or stack of wavelength bands may include (1) one or more narrow bands corresponding to one or more primary colors, and (2) one or more narrow bands and / or broad bands corresponding to one or more of the primary colors or non-primary colors. The wavelength composition in an SPD for a color to be rendered at a pixel of an image display described herein may be set or customized at run-time during an image rendering operation based at least in part on the pixel values ​​(representing colors) to be rendered in the received image data.

[0061] 2F illustrates an example pixel 230-1 within a spatial array / pattern of pixels of an image display. As illustrated, pixel (230-1) includes a group of subpixels (or subpixel unit structures) of different subpixel types, each of which may be labeled "R1," "G1," "B1," "R2," "G2," "B2," etc.

[0062] In some embodiments, when fully on (e.g., corresponding to fully transparent, highest transmittance or highest brightness, etc.), these subpixel types ("R1", "G1", "B1", "R2", "G2", "B2") generate different narrowbands of SPD light that are directed toward the viewer, as shown in FIG. 3A.

[0063] In some embodiments, when fully on (e.g., corresponding to fully transparent, highest transmittance or highest brightness, etc.), as shown in FIG. 3B, the sub-pixel types (“R1”, “G1”, “B1”) generate different narrowband SPD light that is directed toward the viewer, while the sub-pixel types (“R2”, “G2”, “B2”) generate different broadband SPD light that is directed toward the viewer.

[0064] In some embodiments, sub-pixels "R1", "G1", and "B1" in pixel (230-1) can be used or driven to generate light for a viewer that renders three primary colors, each of which represents a respective vertex of a plurality of vertices that define a color gamut shown as a triangle in Figure 3C, i.e., vertices "R1", "G1", and "B1" shown in Figure 3C. The color gamut includes all colors that can be supported or generated by the image display using sub-pixels of types "R1", "G1", and "B1".

[0065] Some or all of the sub-pixels "R2", "G2", and "B2" in pixel (230-1) can be used or driven to generate light for the viewer in wavelength bands other than the wavelength bands in the SPD of sub-pixels "R1", "G1", and "B1". The light for the viewer generated by sub-pixels "R2", "G2", and "B2" in pixel (230-1) can be combined with the light for the viewer generated by sub-pixels "R1", "G1", and "B1" in pixel (230-1) to form a mix or stack of light wavelength bands, widening the wavelength band in the resulting SPD of the overall light for the viewer generated by pixel (230-1).

[0066] Under the techniques described herein, this mixing or stacking of light wavelength bands or the resulting SPD can be tuned at run-time during an image rendering operation by controlling or driving these sub-pixels based on the pixel value rendered by pixel (230-1) to render the color represented by the pixel value and to allow different viewers to perceive the color rendered by pixel (230-1) with a consistent color perception, thereby preventing or reducing metamerism defects in images rendered by the image display.

[0067] For illustrative purposes only, it is described that the resulting SPD of the overall viewer-directed light generated by a pixel can be tuned with three subpixels of a type used to generate narrow wavelength band primary colors, and three additional subpixels of an additional type used to broaden these primary colors or their (e.g., narrow) wavelength bands. It should be noted that in other embodiments, the pixels described herein can include more or fewer subpixel types than those shown in FIG. 2F, as well as other pixel structures other than those shown in FIG. 2F. Additionally, and optionally or alternatively, in some embodiments, a unit structure (e.g., subpixel, etc.) used to broaden the narrow band primary colors generated by a pixel can be shared by two or more pixels. For example, the unit structure can be equidistantly positioned with respect to a group of pixels including the pixel and one or more neighboring pixels. The narrow band primary colors generated by each of the one or more pixels neighboring the pixel can also be broadened by the unit structure.

[0068] 2G, 2H, 2I, and 2J show pixels 230-2, 230-3, 230-4, and 230-4, respectively, which are examples of pixels within a spatial array / pattern of pixels of an image display.

[0069] As shown in FIG. 2G, pixel (230-2) includes a group of subpixels (or subpixel unit structures) of different subpixel types, denoted as "R1 R2," "G1 G2," "B1 B2," etc.

[0070] In a first example, each of the subpixel types ("R1 R2", "G1 G2", "B1 B2") in pixel (230-2) of FIG. 2G may be implemented as subpixels (200-1, 200-2, or 200-3) of FIG. 2A, 2B, or 2C to include two types of light regenerating materials (e.g., QD, luminescent, etc.) that regenerate light in response to receiving injected light of different light sources. By controlling or adjusting different (e.g., UV, blue light, different light wavelengths and / or intensities, different backlight types, etc.) combinations of injected light from the light sources, each of the subpixel types ("R1 R2", "G1 G2", "B1 B2") in pixel (230-2) of FIG. 2G generates different narrowband or broadband SPD light that is directed to the viewer.

[0071] In a second example, each of the subpixel types ("R1 R2", "G1 G2", "B1 B2") in pixel (230-2) of FIG. 2G may be implemented as subpixel (200-4) of FIG. 2D to include an organic light emitting diode (OLED or organic LED) for generating light (e.g., narrow band, etc.) within one of wavelength bands "R1" and "R2" of FIG. 3A or FIG. 3B, and a light regenerating material (e.g., QDs, luminescent, etc.) that regenerates light within the other of wavelength bands "R1" and "R2" of FIG. 3A or FIG. 3B in response to receiving injected light. By controlling or adjusting different combinations (e.g., UV, blue light, different light wavelengths and / or intensities, different backlight types, etc.) of digital drive values ​​to the OLED, the digital drive values ​​to the light source generating the injected light, and / or the digital drive values ​​to control the transmittance of the light valve layer, each of the sub-pixel types ("R1 R2", "G1 G2", "B1 B2") within pixel (230-2) of FIG. 2G generates a different narrowband or broadband SPD light that is directed toward the viewer.

[0072] At run-time during an image rendering operation, sub-pixel "R1 R2" in pixel (230-2) of FIG. 2G can generate up to a maximum intensity for narrowband "R1" of FIG. 3A or FIG. 3B, up to a maximum intensity for narrowband or broadband "R2" of FIG. 3A or FIG. 3B, or any combination of the above. Similarly, sub-pixel "G1 G2" in pixel (230-2) of FIG. 2G can generate up to a maximum intensity for narrowband "G1" of FIG. 3A or FIG. 3B, up to a maximum intensity for narrowband or broadband "G2" of FIG. 3A or FIG. 3B, or any combination of the above. Sub-pixel "B1 B2" in pixel (230-2) of FIG. 2G can generate up to a maximum intensity for narrowband "B1" of FIG. 3A or FIG. 3B, up to a maximum intensity for narrowband or broadband "B2" of FIG. 3A or FIG. 3B, or any combination of the above.

[0073] As shown in Figure 2H, pixel (230-3) includes a group of subpixels (or subpixel unit structures) of different subpixel types, each denoted as "R1", "G1", "B1", "R2", etc. Subpixel "R2" may be used to spread the red primary color in combination with subpixel "R1" of pixel (230-3).

[0074] As shown in FIG. 2I, pixel (230-4) includes a group of subpixels (or subpixel unit structures) of different subpixel types, denoted as “R1 R2”, “G1”, “B1”, etc., respectively. Subpixels “R1 R2” can be used to generate narrowband red primary and broadband red primary using any combination of one or more OLEDs, one or more QD types, and one or more luminescent types.

[0075] The wavelength bands of the primaries may also be broadened with colors that are not similar to the primaries. In the example shown in FIG. 2J, pixel (230-5) includes a group of subpixels (or subpixel unit structures) of different subpixel types, labeled "R1", "G1", "B1", "W", etc. Subpixel "W" may be used to generate a multi-wavelength band white color that may be combined with one, some, or all of the primary colors generated by subpixels "R1", "G1", and / or "B1". In another example shown in FIG. 2K, a group (e.g., five, etc.) of pixels each including a group of subpixels (or subpixel unit structures) of different subpixel types, labeled "R1", "G1", "B1", etc., may share one or more of unit structures "M", "C", and "Y" that generate magenta, cyan, and yellow. These additional unit structures "M", "C", and "Y" can be used to generate single or multiple wavelength bands that can be combined with one, some, or all of the primary colors generated by sub-pixels "R1", "G1", and / or "B1" in the group of pixels. These unit structures can be relatively uniformly or sparsely arranged within the spatial array / pattern of pixels of the image display (102) such that the light from these unit structures is not visually noticeable, but rather plays a supporting role in spreading the wavelength band to prevent or reduce metamerism defects.

[0076] The human visual system (HVS) faces the fewest metamerism defects for narrowband blue light and the least metamerism defects for narrowband green light. In some embodiments, additional subpixel types or additional wavelength bands may be used to broaden the wavelength bands for only a subset of the primary colors, for example, red, red and green (not shown) in the RGB color system as shown in Figures 2H and 2I.

[0077] Under the techniques described herein, the mixing or stacking of light wavelength bands or the resulting SPD can be tuned at run-time during an image rendering operation by controlling or driving these sub-pixels based on the pixel values ​​rendered by the pixels (230-2, 230-3, or 230-4) to render the color represented by the pixel values ​​and to allow different viewers to perceive the color rendered by the pixels (230-2, 230-3, or 230-4) with a consistent color perception, thereby preventing or reducing metamerism defects in images rendered by the image display.

[0078] 7. Saturation / position-based wavelength expansion The pixel value of the pixel may be used to determine or represent the (gamut) location of the color represented by the pixel value in a gamut bounded by a first contour 302 as shown in FIG. 3E (e.g., formed by the most saturated colors supported by the combination of the three primary colors R1, G1, and B1).

[0079] The saturation value (or chroma for short) of the color represented by the pixel value may be estimated, determined, or calculated to represent the (gamut) location of the pixel value using any of a variety of saturation calculation methods. In one example, the saturation value may be estimated, determined, or calculated based at least in part on a distance measure (e.g., expressed as a function of the component pixel values ​​at the pixel value) that measures the linear or non-linear distance between the color and a white point (denoted as "wp") or an applicable (e.g., closest, achromatic, etc.) gray value in the color space in which the gamut is represented. In another example, the saturation value may be estimated, determined, or calculated by using a combination of multiple component pixel values ​​at the pixel value to search or look up a saturation value lookup table indexed with different unique combinations of component pixel values ​​for different possible pixel values.

[0080] The sensitivity or likelihood of an HVS to metamerism defects may depend on several factors, including but not limited to the location or saturation of a color in the color gamut. Highly saturated colors (e.g., green, blue, etc.) may be perceived with consistent color vision by most, if not all, viewers, even when they are rendered in narrow-bandwidth color light. In contrast, mixed colors that are close to the white point may be perceived differently when they are rendered in narrow-bandwidth color light.

[0081] Under other approaches that do not implement the techniques described herein, the entire color gamut (e.g., as depicted by the first contour (302) in FIG. 3E) may be rendered with primary colors (e.g., “R1”, “G1”, and “B1”, each of which has a fixed representative wavelength (e.g., the peak wavelength of the SPD, the midpoint wavelength of a wavelength band, etc.) and a fixed narrow bandwidth. As a result, under these other approaches, metamerism defects are relatively likely to occur in the image display, especially for colors that are low in saturation and close to the white point.

[0082] In contrast, under the techniques described herein, different colors within a color gamut may be rendered with different compositions of light of narrowband or broadband primary colors, and / or other colors than the primaries, and / or other wavelength bands than the narrowband primaries, based at least in part on the specific color location / saturation of the different colors.

[0083] Under the techniques described herein, the color (denoted c) rendered by an image display is c = f(w, bw) (1) As such, light may be rendered with a mix or stack of one or more wavelength bands, each characterized by one or more representative wavelengths, denoted w, and one or more bandwidths, denoted bw, based on a mapping function, denoted f(), where the specific composition of the representative wavelengths w and bandwidths bw in equation (1) may be adjusted or set at run-time during an image rendering operation based at least in part on the specific location or saturation of the color c in the color gamut.

[0084] The mapping function f() maps a particular SPD, represented by a mixture or stack of one or more wavelength bands, to a particular color (c) perceived by the HVS. The mapping function can be constructed using a tristimulus color matching function that integrates over the SPD to obtain the corresponding tristimulus value perceived by the HVS. A particular color (c), e.g., RGB pixel values, YCbCr pixel values, etc., can be obtained from the tristimulus values ​​calculated using the tristimulus matching function based on the particular SPD.

[0085] The representative wavelength may be the peak wavelength, the midpoint wavelength, etc. of the corresponding wavelength band. The bandwidth corresponding to the representative wavelength may be a measure of the width of the wavelength band.

[0086] For illustrative purposes only, a step function is used in Figures 3A and 3B to describe or represent the light intensity distributed across a wavelength range or band. It should be noted that in various embodiments, functions other than a step function may be used to describe or represent the light intensity distributed across a wavelength range or band.

[0087] In some embodiments, the color gamut of FIG. 3E can be partitioned into three distinct color gamut regions: a first color gamut region between the first contour (302) and the second contour (304), a second color gamut region between the second contour (304) and the third contour (306), and a third color gamut region within the third contour (306). Colors in the first color gamut region have the highest saturation, are located the furthest from the white point, and are least susceptible to metamerism defects. Colors in the third color gamut region have the lowest saturation, are located the closest to the white point, and are most susceptible to metamerism defects. Colors in the second color gamut region have intermediate saturation, are located an intermediate distance to the white point, and are somewhat more susceptible to metamerism defects.

[0088] These contours are shown as triangles in FIG. 3E, but it should be noted that in various embodiments, contours of different shapes and / or a different number of contours and / or different ways of dividing the gamut may be used to create or identify different gamut regions.

[0089] In some embodiments, the image display, or each pixel therein, C=F(f(w1,bw1),f(w2,bw2),f(w3,bw3)) (2) The color control function denoted F() can be implemented to generate light of a color to be rendered, denoted C, using three primary colors that are set or controlled based on the color control function denoted F() as follows: where f(w1, bw1) represents a first primary color generated by a first SPD having light of one or more first wavelength bands defined by one or more first representative wavelengths w1 and one or more first wavelength bands bw1, f(w2, bw2) represents a second primary color generated by a second SPD having light of one or more second wavelength bands defined by one or more second representative wavelengths w2 and one or more second wavelength bands bw2, and f(w3, bw3) represents a third primary color generated by a third SPD having light of one or more third wavelength bands defined by one or more third representative wavelengths w3 and one or more third wavelength bands bw3.

[0090] The color gamuts described herein may be defined by more than three primary colors to increase the color volume or total number of colors supported by the image displays described herein. As shown in FIG. 3D, the color gamut formed by the four primary colors "R1", "G1", "B1", and "P" is larger than the color gamut formed by the three primary colors "R1", "G1", and "B1".

[0091] In some embodiments, the image display, or each pixel therein, C=NF(f(w1,bw1),f(w2,bw2),…) (3) The color control function may be implemented to generate light of the color to be rendered, denoted C, using two, three, four or more primary colors that are set or controlled based on a color control function, denoted NF(), as follows:

[0092] In an image rendering operation, as the color to be rendered approaches the most saturated, such as within the first gamut region of FIG. 3E, one or more of the primary colors used to render the color (e.g., in equations (2) or (3) above) may be changed to narrower and narrower wavelength bands.

[0093] In contrast, as the color to be rendered approaches the least saturated, such as within the third gamut region of FIG. 3E, one or more of the primary colors used to render the color (e.g., in equation (2) or (3) above) may be changed to wider and wider wavelength bands (each of which may have multiple narrow bands).

[0094] For a color to be rendered that has intermediate saturation, such as within the second gamut region of FIG. 3E, one or more of the primary colors used to render the color (e.g., in equation (2) or (3) above) may be changed to a wavelength band of intermediate bandwidth.

[0095] Under other approaches that do not implement the techniques described herein, an image display may use a subpixel type, such as a red subpixel type, to represent only a primary color that corresponds to a color component / channel of a color space (in this example, a red component / channel), and thus a component pixel value (in this example, a red component pixel value) of a pixel value rendered by a pixel is all that is needed to drive a corresponding subpixel or corresponding red subpixel within that pixel.

[0096] In contrast, under the techniques described herein, other component pixel values ​​of the (overall) pixel value rendered by a pixel may be used in conjunction with the component pixel values ​​to drive corresponding sub-pixels within the pixel to render the primary color represented by that component pixel value. For example, those other component values ​​may be used in conjunction with the component pixel values ​​to determine the location or saturation of the color represented by the (overall) pixel value. The location or saturation of the color may be used to determine a bandwidth composition for the primary color represented by the component pixel value, and thereby determine the digital control values ​​to be used to generate that bandwidth composition by the pixel for the primary color.

[0097] As previously mentioned, color filters can be included in the unit structures described herein to prevent ambient light from adversely affecting the unit structure's image rendering operation. The color filters can be designed to pass transmitted light that is used to render color to the viewer.

[0098] In one example, a red (e.g., non-QD with red pigment) color filter can be used with a unit structure having a red QD material. The red color filter can have a passband that allows the recycled red light from the red QD material to pass toward the viewer. In another example, a non-red color filter can be used with the QD color filter, so long as the non-red color filter passes the recycled light from the QD color filter. The non-red color filter can filter out only the blue ambient light that can excite or stimulate the red QD material and thus be part of the injected light that can interfere with the display operation of the red QD color filter.

[0099] Additionally, optionally or alternatively, multi-band color filters may be used in the unit structures described herein to allow only certain wavelengths in the transmission wavelength band to pass through and block all other wavelengths.

[0100] In unit structures designated to produce white and combine or extend the primary colors, white can be produced using a mixture of different types of QD materials. Similar color filter configurations can be used for the white unit structures described herein.

[0101] In some embodiments, light regenerating materials can be incorporated into light valve layers, optical stacks, backlight units, color filters, etc. to generate image rendering light and / or to recycle the backlight of the backlight unit for illumination light in light valve layers, diffuser films, etc.

[0102] 8. Process Flow Example 4 illustrates an example of a process flow according to one embodiment. In some embodiments, one or more computing devices or components (e.g., an image rendering device, etc.) may perform this process flow. At block 402, an image processing system receives image data for rendering an image to a viewer on an image display, the image data defining pixel values ​​of the image to be rendered for pixels of the image display, the pixel values ​​for the pixels including multiple component pixel values ​​corresponding to multiple color components of a color space.

[0103] At block 404, the image processing system calculates a gamut location value for the pixel value based on two or more of the component pixel values ​​of the pixel value defined for the pixel.

[0104] At block 406, the image processing system uses the gamut position value to determine whether to apply bandwidth expansion to the image rendering light generated by the pixels of the image display to render the pixel values, and the image rendering light is directed to the viewer.

[0105] In one embodiment, the image rendering light comprises light from one or more of quantum dots, remote phosphor materials, luminescent materials, laser light sources, light emitting diodes (LEDs), organic LEDs, cold cathode fluorescent lamps (CCFLs), and the like.

[0106] In one embodiment, the pixel has three or more sub-pixels, and in response to determining that bandwidth expansion should be applied to the image rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven to generate a portion of the image rendering light in the additional wavelength band.

[0107] In one embodiment, the pixel has three or more sub-pixels, and in response to determining that no bandwidth expansion should be applied to the image rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven so that it does not generate a portion of the image rendering light in the additional wavelength band.

[0108] In one embodiment, a pixel has three or more sub-pixels configured to be digitally driven to generate light of three or more primary colors that define a color gamut, the color gamut including all colors supported by the pixel, and the light of the three or more primary colors without bandwidth expansion renders each of the three or more primary colors within a narrow wavelength band.

[0109] In one embodiment, a pixel has a unit structure for generating at least a portion of the image rendering light, the unit structure representing one of a subpixel having a light regenerating color filter without a non-light regenerating color filter, a subpixel having a light regenerating color filter in addition to a non-light regenerating color filter, a subpixel having no color filter, a subpixel having a light valve layer portion disposed thereon, a subpixel having an optical stack in a backlight unit having a light regenerating layer portion disposed thereon, a subpixel having no light regenerating material, a subpixel having an organic light emitting diode (OLED), a subpixel having a micro LED, a subpixel having a single light valve layer portion belonging to a single light valve layer, a subpixel having multiple light valve layer portions belonging to multiple light valve layers, a subpixel having one or more liquid crystal layer portions belonging to one or more liquid crystal layers, a subpixel having a light diffuser, a subpixel having a finish polarizer, a subpixel having an in-cell polarizer, a subpixel having a side-emitting light source, a subpixel having a back-emitting light source, etc.

[0110] In one embodiment, a pixel has three or more primary color sub-pixels configured to be digitally driven to generate light of three or more primary colors, each within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to generate light in a wavelength band adjacent to at least one of the three or more narrow wavelength bands.

[0111] In one embodiment, a pixel has three or more sub-pixels, at least one of which is configured to be digitally driven to generate light of a primary color within a narrow wavelength band and a separate sub-pixel configured to be digitally driven to generate light of a wavelength band adjacent to the narrow wavelength band.

[0112] In one embodiment, a pixel has three or more primary color sub-pixels configured to be digitally driven to generate three or more primary color light, each within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to generate white light.

[0113] In one embodiment, the image display includes a group of adjacent pixels to which the pixel belongs, each pixel in the group of adjacent pixels generating light of a primary color, each primary color within a narrow wavelength band, and the group of adjacent pixels sharing one or more unit structures configured to be digitally driven to generate light of wavelength bands adjacent to the narrow wavelength bands of the primary color light.

[0114] In one embodiment, the bandwidth expansion depends at least in part on the saturation represented in the gamut position value.

[0115] In one embodiment, the color space represents one of the following: an RGB color space, a YCbCr color space, an IPT color space, an ICtCp color space, other color spaces, and the like.

[0116] In one embodiment, a display system includes an image display and display control logic implemented at least in part by one or more computer processors to control image rendering operations associated with the image display, the display control logic configured to perform any of the methods or process flows described above.

[0117] In one embodiment, a computing device, such as a display device, a mobile device, a set-top box, a multimedia device, etc., is configured to perform any of the above-mentioned methods. In one embodiment, an apparatus has a processor and is configured to perform any of the above-mentioned methods. In one embodiment, a non-transitory computer-readable storage medium stores software instructions that, when executed by one or more processors, cause the execution of any of the above-mentioned methods.

[0118] In one embodiment, a computing device has one or more processors and one or more storage media having stored thereon a set of instructions that, when executed by the one or more processors, causes the execution of any of the methods described above.

[0119] It should be noted that although separate embodiments are described herein, the embodiments and / or sub-embodiments described herein may be combined in any combination to form further embodiments.

[0120] 9. Computer System Implementation Examples Embodiments of the invention may be implemented in a computer system, a system comprised of electronic circuits and components, such as an integrated circuit (IC) device, such as a microcontroller, a field programmable gate array (FPGA) or other configurable or programmable logic device (PLD), a discrete time or digital signal processor (DSP), an application specific IC (ASIC), and / or an apparatus including one or more of such systems, devices, or components. The computer and / or IC may execute, control, or perform instructions relating to adaptive perceptual quantization of images having enhanced dynamic range, such as those described herein. The computer and / or IC may calculate any of the various parameters or values ​​associated with the adaptive perceptual quantization process described herein. Image and video embodiments may be implemented in hardware, software, firmware, and various combinations thereof.

[0121] Certain embodiments of the present invention include a computer processor that executes software instructions that cause the processor to perform the methods of the present disclosure. For example, one or more processors in a display, an encoder, a set-top box, a transcoder, or the like may perform the method for adaptive perceptual quantization of HDR images described above by executing software instructions in a program memory accessible to the processor. The embodiments of the present invention may also be provided in the form of a program product. The program product may include any non-transitory medium that carries a set of computer-readable signals having instructions that, when executed by a data processor, cause the data processor to perform the methods of the embodiments of the present invention. A program product according to an embodiment of the present invention may be in any of a wide variety of forms. The program product may include a physical medium, such as, for example, a magnetic data storage medium including a floppy disk, a hard disk drive, an optical data storage medium including a CD ROM, a DVD, an electronic data storage medium including a ROM, a flash RAM, or the like. The computer-readable signals on the program product may be optionally compressed or encrypted.

[0122] When a component (e.g., a software module, processor, assembly, device, circuit, etc.) is referred to above, unless otherwise noted, the reference to that component (including the reference to a "means") should be interpreted to include any component that performs the function of the described component (e.g., is functionally equivalent) as equivalent to that component, including components that are not structurally equivalent to the disclosed structures that perform that function in the illustrated embodiment of the invention.

[0123] According to one embodiment, the techniques described herein are implemented by one or more special-purpose computing devices. The special-purpose computing devices may be hardwired to perform the techniques, may include digital electronic devices, such as one or more application-specific integrated circuits (ASICs) or field programmable gate arrays (FPGAs), that are permanently programmed to perform the techniques, or may include one or more general-purpose hardware processors that are programmed to perform the techniques according to program instructions in firmware, memory, other storage, or a combination. Such special-purpose computing devices may also combine custom hardwired logic, ASICs, or FPGAs with custom programming to achieve the techniques. The special-purpose computing devices may be desktop computer systems, portable computer systems, handheld devices, networking devices, or any other devices incorporating hardwired and / or program logic to implement the techniques.

[0124] For example, Figure 5 is a block diagram illustrating a computer system 500 in which embodiments of the invention may be implemented. Computer system 500 includes a bus 502 or other communication mechanism for communicating information, and a hardware processor 504 coupled with bus 502 for processing information. Hardware processor 504 may be, for example, a general-purpose microprocessor.

[0125] Computer system 500 also includes a main memory 506, such as a random access memory (RAM) or other dynamic storage device, coupled to bus 502 for storing information and instructions executed by processor 504. Main memory 506 may also be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 504. Such instructions, when stored on a non-transitory storage medium accessible to processor 504, render computer system 500 a special-purpose machine customized to perform the operations specified in the instructions.

[0126] Computer system 500 further includes a read only memory (ROM) 508 or other static storage device coupled to bus 502 for storing static information and instructions for processor 504. A storage device 510, such as a magnetic disk or optical disk, is provided and coupled to bus 502 for storing information and instructions.

[0127] Computer system 500 may be coupled via bus 502 to a display 512, such as a liquid crystal display, for displaying information to a computer user. An input device 514, including alphanumeric and other keys, is coupled to bus 502 for communicating information and command selections to processor 504. Another type of user input device is a cursor control 516, such as a mouse, trackball, or cursor direction keys, for communicating directional information and command selections to processor 504 and for controlling cursor movement on display 512. This input device may typically have two degrees of freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y), that allow the device to define a position in a plane.

[0128] The computer system 500 may implement the techniques described herein using customized hardwired logic, one or more ASICs or FPGAs, firmware, and / or program logic that combines with the computer system to make or program the computer system 500 a dedicated machine. According to one embodiment, the techniques described herein are performed by the computer system 500 in response to the processor 504 executing one or more sequences of one or more instructions contained in the main memory 506. Such instructions may be read into the main memory 506 from another storage medium, such as the storage device 510. Execution of the sequences of instructions contained in the main memory 506 causes the processor 504 to perform the process steps described herein. In alternative embodiments, hardwired circuitry may be used in place of or in combination with software instructions.

[0129] The term "storage media" as used herein refers to any non-transitory medium that stores instructions and / or data that cause a machine to operate in a specific manner. Such storage media may include non-volatile media and / or volatile media. Non-volatile media include, for example, optical or magnetic disks, such as storage device 510. Volatile media include, for example, dynamic memory, such as main memory 506. Common forms of storage media include, for example, floppy disks, flexible disks, hard disks, solid state drives, magnetic tape, or any other magnetic data storage medium, CD-ROMs, any other optical data storage medium, any physical medium with a pattern of holes, RAM, PROM, and EPROM, FLASH-EPROM, NVRAM, any other memory chip or cartridge.

[0130] Storage media is distinct from, but may be used in conjunction with, transmission media. Transmission media involves transferring information between storage media. For example, transmission media include coaxial cables, copper wire, and fiber optics, including the wires that comprise bus 502. Transmission media can also take the form of acoustic or light waves, such as those generated in radio wave and infrared data communications.

[0131] Various forms of media may be involved in carrying one or more sequences of one or more instructions to the processor 504 for execution. For example, the instructions may initially be carried on a magnetic disk or solid state drive of a remote computer. The remote computer may load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to the computer system 500 can receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector can receive the data carried in the infrared signal and appropriate circuitry can place the data on the bus 502. The bus 502 carries the data to main memory 506, from which the processor 504 retrieves and executes the instructions. The instructions received by main memory 506 may optionally be stored on a storage device 510 either before or after execution by the processor 504.

[0132] Computer system 900 also includes a communications interface 518 coupled to bus 502. The communications interface 518 provides a two-way data communication coupling to a network link 520 that is connected to a local network 522. For example, the communications interface 518 may be an integrated services digital network (ISDN) card, cable modem, satellite modem, or a modem providing a data communication connection to a corresponding type of telephone line. As another example, the communications interface 518 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, the communications interface 518 sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information.

[0133] Network link 520 typically provides data communication through one or more networks to other data devices. For example, network link 520 may provide a connection through a local network 522 to a host computer 524 or to data equipment operated by an Internet Service Provider (ISP) 526. ISP 526, in turn, provides data communication services through the world wide packet data communication network now commonly referred to as the “Internet” 528. Local network 522 and Internet 528 both use electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on network link 520 through communication interface 518, which carry the digital data to and from computer system 500, are exemplary forms of transmission media.

[0134] Computer system 500 can send messages and receive data, including program code, through the network(s), network link 520 and communication interface 518. In the Internet example, a server 530 might transmit a requested code for an application program through Internet 528, ISP 526, local network 522 and communication interface 518.

[0135] The received code may be executed by processor 504 as it is received, and / or stored in storage device 510, or other non-volatile storage for later execution.

[0136] 10. Equivalence, extension, substitution, and miscellaneous In the foregoing specification, embodiments of the invention have been described with reference to numerous specific details that may vary from implementation to implementation. Thus, the only and exclusive indication of what is and is intended by the applicant to be the claimed embodiments of the invention is the set of claims issued from this application in the particular form in which such claims arise, including any subsequent amendments. The definitions expressly set forth herein for terms contained in such claims shall govern the meaning of such terms as used in the claims. Thus, no limitations, elements, properties, features, advantages, or attributes expressly recited in the claims should in any way limit the scope of such claims. Thus, the specification and drawings should be regarded in an illustrative sense, and not in a restrictive sense.

[0137] Various aspects and implementations of the present disclosure can be understood from the following enumerated example embodiments (EEE), which are not claims.

[0138] EEE1. Receiving image data for rendering an image to a viewer on an image display, the image data defining, for a pixel of the image display, a pixel value of the image to be rendered, the pixel value for the pixel including a plurality of component pixel values ​​corresponding to a plurality of color components of a color space; calculating a gamut location value for the pixel value based on two or more of the plurality of component pixel values ​​of the pixel value defined for the pixel; determining using the gamut location value whether to apply bandwidth expansion to image rendering light generated by the pixel of the image display to render the pixel value; and directing the image rendering light to the viewer. How to have that.

[0139] EEE2. The method of EEE1, wherein the image-rendering light comprises light from one or more of quantum dots, remote phosphor materials, luminescent materials, laser light sources, light emitting diodes (LEDs), organic LEDs, or cold cathode fluorescent lamps (CCFLs).

[0140] EEE3. The method of EEE1 or 2, wherein the pixel has three or more sub-pixels, and in response to determining that bandwidth expansion should be applied to the image-rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven to generate a portion of the image-rendering light within an additional wavelength band.

[0141] EEE4. Any of the methods of EEE1 to 3, wherein the pixel has three or more sub-pixels, and in response to determining that bandwidth expansion should not be applied to the image-rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven so as not to generate a portion of the image-rendering light in an additional wavelength band.

[0142] EEE5. Any of the methods of EEE1-4, wherein the pixel has three or more sub-pixels configured to be digitally driven to generate light of three or more primary colors defining a color gamut, the color gamut including all colors supported by the pixel, and the light of the three or more primary colors without bandwidth expansion renders each of the three or more primary colors within a narrow wavelength band.

[0143] EEE6. Any of the methods of EEE1 to 5, wherein the pixel has unitary structures for generating at least a portion of the image rendering light, the unitary structures representing one of: a subpixel having a light regenerating color filter without a non-light regenerating color filter, a subpixel having a light regenerating color filter in addition to a non-light regenerating color filter, a subpixel having no color filter, a subpixel having a light valve layer portion disposed thereon, a subpixel in a backlight unit having an optical stack having a light regenerating layer portion disposed thereon, a subpixel having no light regenerating material, a subpixel having an organic light emitting diode (OLED), a subpixel having a micro LED, a subpixel having a single light valve layer portion belonging to a single light valve layer, a subpixel having multiple light valve layer portions belonging to multiple light valve layers, a subpixel having one or more liquid crystal layer portions belonging to one or more liquid crystal layers, a subpixel having a light diffuser, a subpixel having a finish polarizer, a subpixel having an in-cell polarizer, a subpixel having a side emitting light source, or a subpixel having a back emitting light source.

[0144] EEE7. Any of the methods of EEE1 to 6, wherein the pixel has three or more primary color sub-pixels configured to be digitally driven to generate light of three or more primary colors, respectively, within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to generate light in a wavelength band adjacent to at least one of the three or more narrow wavelength bands.

[0145] EEE8. Any of the methods of EEE1 to 7, wherein the pixel has three or more sub-pixels, at least one of the three or more sub-pixels being configured to be digitally driven to generate light of a primary color within a narrow wavelength band and separately configured to be digitally driven to generate light in wavelength bands adjacent to the narrow wavelength band.

[0146] EEE9. Any of the methods of EEE1 to 8, wherein the pixel has three or more primary color sub-pixels configured to be digitally driven to produce three or more primary color light, each within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to produce white light.

[0147] EEE10. Any of the methods of EEE1 to 9, wherein the image display includes a group of adjacent pixels to which the pixel belongs, each pixel in the group of adjacent pixels generating light of a primary color, each pixel being a primary color within a narrow wavelength band, and the group of adjacent pixels sharing one or more unit structures configured to be digitally driven to generate light in wavelength bands adjacent to the narrow wavelength bands of the primary color light.

[0148] EEE11. Any of the methods of EEE1-10, wherein the bandwidth expansion is at least partially dependent on saturation represented in the gamut location values.

[0149] EEE12. Any of the methods of EEE1 to 11, wherein the color space represents one of an RGB color space, a YCbCr color space, an IPT color space, an ICtCp color space, or another color space.

[0150] EEE13. A display system comprising: An image display; display control logic implemented at least in part by one or more computer processors for controlling image rendering operations associated with said image display; having the display control logic is configured to perform any of the methods of EEE1 to EEE12. Display system.

[0151] EEE14. A non-tangible computer readable storage medium having stored thereon software instructions which, when executed by one or more computer processors, cause the performance of any of the methods of EEE1 to EEE12.

[0152] EEE15. An apparatus having one or more computer processors and one or more storage media having a set of instructions stored thereon, said set of instructions, when executed by said one or more computer processors, causing the performance of any of the methods of EEE1 to EEE12.

Claims

1. receiving image data for rendering an image to a viewer on an image display, the image display having an array of pixels arranged in a spatial pattern, the image data defining pixel values ​​of the image to be rendered for pixels of the image display, the pixel values ​​for the pixels including a plurality of component pixel values ​​corresponding to a plurality of color components of a color space; calculating a gamut location value for the pixel value based on two or more component pixel values ​​of the plurality of component pixel values ​​for the pixel value defined for the pixel; using the gamut location value to determine whether to apply bandwidth expansion to image rendering light generated by the pixels of the image display to render the pixel values ​​such that metamerism defects are prevented or reduced, and the image rendering light is directed to the viewer to render the image to the viewer. How to have that.

2. 10. The method of claim 1, wherein the image rendering light comprises light from one or more of quantum dots, remote phosphor materials, luminescent materials, laser light sources, light emitting diodes (LEDs), organic LEDs, or cold cathode fluorescent lamps (CCFLs).

3. 2. The method of claim 1 , wherein the pixel has three or more sub-pixels, and in response to determining that bandwidth expansion should be applied to the image-rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven to generate a portion of the image-rendering light in an additional wavelength band.

4. 4. The method of claim 3, wherein the bandwidth expansion comprises overlapping portions of the image-rendering light produced by the three or more sub-pixels to form a mix or stack of image-rendering light of different wavelength bands.

5. 2. The method of claim 1 , wherein the pixel has three or more sub-pixels, and in response to determining that no bandwidth expansion should be applied to the image-rendering light, at least one sub-pixel of the three or more sub-pixels is digitally driven to not generate a portion of the image-rendering light in an additional wavelength band.

6. 2. The method of claim 1 , wherein the pixel has three or more sub-pixels configured to be digitally driven to generate light of three or more primary colors that define a color gamut, the color gamut including all colors supported by the pixel, and the light of the three or more primary colors without bandwidth expansion renders each of the three or more primary colors within a narrow wavelength band.

7. 2. The method of claim 1 , wherein the pixel has unit structures for generating at least a portion of the image rendering light, the unit structures representing one of: a subpixel having a light regenerating color filter without a non-light regenerating color filter, a subpixel having a light regenerating color filter in addition to a non-light regenerating color filter, a subpixel having no color filter, a subpixel having a light valve layer portion disposed thereon, a subpixel having an optical stack in a backlight unit having a light regenerating layer portion disposed thereon, a subpixel having no light regenerating material, a subpixel having an organic light emitting diode (OLED), a subpixel having a microLED, a subpixel having a single light valve layer portion belonging to a single light valve layer, a subpixel having multiple light valve layer portions belonging to multiple light valve layers, a subpixel having one or more liquid crystal layer portions belonging to one or more liquid crystal layers, a subpixel having a light diffuser, a subpixel having a finish polarizer, a subpixel having an in-cell polarizer, a subpixel having a side-emitting light source, or a subpixel having a back-emitting light source.

8. 2. The method of claim 1, wherein the pixel has three or more primary color sub-pixels configured to be digitally driven to generate light of three or more primary colors, respectively, within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to generate light in a wavelength band adjacent to at least one of the three or more narrow wavelength bands.

9. 2. The method of claim 1 , wherein the pixel comprises three or more sub-pixels, at least one of the three or more sub-pixels configured to be digitally driven to generate light of a primary color within a narrow wavelength band and separately configured to be digitally driven to generate light of a wavelength band adjacent to the narrow wavelength band.

10. 10. The method of claim 1, wherein the pixel has three or more primary color sub-pixels configured to be digitally driven to generate three or more primary color light, respectively, within three or more narrow wavelength bands, and the pixel has at least one additional sub-pixel configured to be digitally driven to generate white light.

11. 2. The method of claim 1, wherein the image display includes a group of adjacent pixels to which the pixel belongs, each pixel in the group of adjacent pixels generating light of a primary color, each pixel being a primary color within a narrow wavelength band, and the group of adjacent pixels sharing one or more unit structures configured to be digitally driven to generate light of wavelength bands adjacent to the narrow wavelength bands of the primary color light.

12. The method of claim 1 , wherein the bandwidth expansion depends at least in part on the saturation represented in the gamut position values.

13. 13. The method of claim 12, wherein the saturation is determined by using the combination of component pixel values ​​in the pixel value to look up a saturation value lookup table indexed with different unique combinations of component pixel values ​​for different possible pixel values.

14. The method of claim 1 , wherein the color space represents one of an RGB color space, a YCbCr color space, an IPT color space, an ICtCp color space, or another color space.

15. The method of claim 1 , further comprising deriving the image from the image data and rendering the image on the image display using the image rendering light.

16. An image display; display control logic implemented at least in part by one or more computer processors for controlling image rendering operations associated with said image display; having The display control logic is configured to perform a method according to any one of claims 1 to 15. Display system.

17. A non-tangible computer readable storage medium having stored thereon software instructions which, when executed by one or more computer processors, cause the performance of a method according to any one of claims 1 to 15.

18. 16. An apparatus having one or more computer processors and one or more storage media having a set of instructions stored thereon, the set of instructions, when executed by the one or more computer processors, causing the performance of a method according to any one of claims 1 to 15.

Images