Image display screen and method for manufacturing an image display screen and storage medium

Abstract

One or more punch pattern methods are applied (402) to generate a spatial distribution of punches that forms a semi-random pattern for an image display screen. The image display screen is punched (404) with the spatial distribution of punches that forms the semi-random pattern. An image rendering light is emitted (406) by a light projector toward the image display screen mounted in an image rendering environment. The image display screen reflects (408) at least a portion of the image rendering light emitted from the light projector toward a viewer.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 064,517 filed August 12, 2020, and European Patent Application No. 20190641.9 filed August 12, 2020, both of which are incorporated by reference herein in their entirety. TECHNICAL FIELD

[0003] The present invention relates generally to image displays, and in particular to moire reduction with controlled aperture locations in image displays or screens. SUMMARY

[0004] According to a first aspect of the present disclosure, there is provided an image display screen comprising: a spatial distribution of perforations forming a semi-random pattern to reduce moire patterns in image rendering operations, wherein the perforations in the semi-random pattern have varying individual spatial displacements with respect to pixels; wherein the image display screen is configured to reflect at least a portion of image rendering light emitted from a light projector towards a viewer; wherein the image display screen comprises a plurality of webs connected along one or more seam edges; and wherein the spatial distribution of perforations on the image display screen tends to change from the semi-random pattern to a regular aperture pattern towards the one or more seam edges.

[0005] According to a second aspect of the present disclosure, there is provided a method of manufacturing an image display screen, the method comprising: applying one or more perforation pattern methods to generate a spatial distribution of perforations forming a semi-random pattern for the image display screen to reduce moire patterns in image rendering operations, wherein the perforations in the semi-random pattern have varying individual spatial displacements with respect to pixels; perforating the image display screen with the spatial distribution of perforations forming the semi-random pattern; providing a plurality of webs connected along one or more seam edges of the image display screen; wherein the spatial distribution of perforations on the image display screen tends to change from the semi-random pattern to a regular aperture pattern towards the one or more seam edges.

[0006] According to a third aspect of the present disclosure, there is provided a non-transitory computer readable storage medium storing software instructions that, when executed by one or more processors, cause performance of the above-mentioned method.

[0007] According to a fourth aspect of the present disclosure, there is provided an image display apparatus comprising one or more processors and one or more storage media storing a set of instructions that, when executed by the one or more processors, cause performance of the above-mentioned method. BACKGROUND

[0008] Screens in digital cinema installations have regular, patterned apertures that allow sound waves from audio speakers behind the screen to pass through toward the viewers. In such cinema installations, light rendering an image can be emitted from a digital cinema projector (or any digital projector), projected onto such a screen, and reflected from the screen toward the viewers. The light emitted from the projector onto the screen is modulated by a spatial distribution pattern of amplitude variations in the screen reflectivity. These amplitude variations are at least partially affected by the presence of the apertures on the screen. When the apertures on the screen and the visual representation of the pixels of the projected image have spatial frequencies that form a rational relationship, a visually perceptible beat of the lower spatial frequency can occur and become very noticeable. (A rational relationship is formed between two spatial frequencies if the ratio of the spatial frequencies of the pixel pattern to the spatial frequencies of the aperture pattern can be expressed as a ratio of two integers.) This type of visual artifact, known as a Moire pattern, is not depicted in the image by the content creator, nor is it intended by the content creator to be depicted in the image, but is caused by certain relationships and interactions between the spatial frequencies or variations of the aperture pattern and the spatial frequencies or variations of image features or textures in the image.

[0009] The methods described in this section are methods that can be employed, but are not necessarily the methods that have been previously conceived or employed. Therefore, unless otherwise indicated herein, none of the methods described in this section should be deemed to be the prevailing art merely by virtue of their inclusion in this section. Similarly, unless otherwise indicated herein, problems identified in the art with respect to any method should not be assumed to have been addressed by the methods described in this section. BRIEF DESCRIPTION OF DRAWINGS

[0010] The application is illustrated in the accompanying drawings, which are by way of illustration and not limitation, and in which like reference numerals refer to similar elements and in which:

[0011] Figure 1A An example modified fixed aperture pattern is illustrated; Figure 1B An example square pixel pattern superimposed with a modified fixed aperture pattern is illustrated; Figure 1C An example Moire pattern that can be generated with a pixel pattern as Figure 1B An example Moire pattern that can be generated with a pixel pattern as

[0012] Figure 2A An example semi-random aperture pattern is illustrated; Figure 2B An example square pixel pattern superimposed with a semi-random aperture pattern is illustrated; Figure 2C An example Moire pattern that can be generated with a pixel pattern as Figure 2BAn example moiré pattern generated from the pixel pattern illustrated in the middle;

[0013] Figure 3A An example theater is illustrated; Figure 3B An example screen is illustrated;

[0014] Figure 4 An example process flow is illustrated; and

[0015] Figure 5 An example hardware platform on which a computer or computing device as described herein can be implemented is illustrated. DETAILED DESCRIPTION

[0016] Example embodiments are described herein that relate to achieving moiré reduction with controlled perforation locations. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present application. It will be apparent, however, that the present application can be practiced without these specific details. In other instances, well-known structures and devices are not described in exhaustive detail, in order to avoid unnecessarily

[0017] Example embodiments are described herein according to the following summary:

[0018] 1. OVERALL SUMMARY

[0019] 2. REGULAR PERFORATION PATTERN

[0020] 3. SEMI-RANDOM PERFORATION PATTERN

[0021] 4. SYSTEM CONFIGURATION

[0022] 5. EXAMPLE PROCESS FLOW

[0023] 6. IMPLEMENTATION MECHANISMS - HARDWARE OVERVIEW

[0024] 7. EQUIVALENTS, EXTENSIONS, ALTERNATIVES, AND OTHERS

[0025] 1. OVERALL SUMMARY

[0026] This overview introduces basic descriptions of some aspects of example embodiments of the application. It should be noted that this overview is not a comprehensive or exhaustive summary of aspects of the example embodiments. Moreover, it should be noted that this overview is not intended to be understood as identifying any particularly important aspects or elements of the example embodiments nor is it intended to be specifically drawn to any particular scope of the example embodiments nor is it intended to be generally drawn to the present application. This overview merely introduces some concepts related to the example embodiments in a compressed and simplified format and is to be understood merely as a conceptual precursor to the more detailed descriptions of the example embodiments that follow. Note that although separate embodiments are discussed herein, any combination of the embodiments and / or portions thereof discussed herein can be combined to form further embodiments.

[0027] Under the techniques as described herein, the eyelet positions on a screen or image display can be generated in a semi-random pattern such that moire patterns are reduced or eliminated. Perforation holes punched or formed in the screen in these positions allow sound (waves) produced by a (audio) speaker behind the screen to propagate relatively freely to a viewer / listener. The screen can be installed in a cinema, movie theater, entertainment venue, amusement park, etc., where moire is a significant problem.

[0028] In some operational scenarios, halftoning techniques can be used to produce or generate eyelet positions in a semi-random pattern that is spatially random but has no or only very little low frequency patterns that can be visually observed on the screen as non-uniformities on the screen. These techniques can provide uniformity of the perforation distribution, reduce or avoid generation of moire patterns in the image rendering operation while maintaining the required eyelet density and area for sound to pass out from behind the screen.

[0029] In some operational scenarios, noise generation / injection techniques can be used to modify a regular eyelet pattern, such as a commercially available digital eyelet or standard eyelet pattern, such that the resulting eyelet positions do not form a regular grid that is prone to cause moire patterns. Additionally, optionally, or alternatively, filtering can be applied to generate a high-pass filtered spatially random or semi-random noise (e.g., with a uniform amplitude distribution, etc.) that can be added to the x and y positions of the grid points or vertices of the regular eyelet grid.

[0030] A selected amount of high-pass filtered noise can be implemented taking into account that visual features in the image rendered on the screen are further low-pass filtered by the human visual system at or beyond a specified distance to reduce or prevent non-uniformities of the resulting semi-random pattern to be visible on the screen to a viewer at or beyond the specified distance. Additionally, optionally, or alternatively, the selected amount of noise can be set to be significantly smaller than the eyelet pitch of the regular eyelet grid, e.g., to avoid placing eyelet positions at edges of a mesh used to form the screen.

[0031] The hole positions as described herein can be derived based on a reference hole grid (logically present but not physically visible) on a screen made from one or more screen material webs (e.g., cut from a screen material roll, etc.). Cutting and joining the screen material webs to form the screen can be performed according to the original grid point positions in the reference hole grid without introducing a DC offset that affects the uniformity of the reference hole grid logically imposed on the screen. Thus, the screen material webs can be seamed, stitched, and / or welded according to the reference hole grid without creating visible artifacts caused by a DC offset in the resulting screen.

[0032] Further, the semi-random hole position generation techniques (e.g., noise generation / injection techniques, halftoning techniques, etc.) can be modified and / or combined to reduce the amplitude of the noise or the spatial displacement from regular grid points or vertices when a hole is near an edge of the web. Thus, the positions of the holes can tend to become or switch to the original regular hole pattern near the edges of the web to avoid creating visible artifacts around the edges of the web, such as half-holes, visible misalignments, etc.

[0033] Example embodiments described herein relate to an image display system. An image display system includes an image display screen including a spatial distribution of perforations forming a semi-random pattern; a light projector emitting image rendering light toward the image display screen. The image display screen reflects at least a portion of the image rendering light emitted from the light projector toward a viewer.

[0034] Example embodiments described herein relate to an image display system. One or more perforation pattern methods are applied to generate a spatial distribution of perforations forming a semi-random pattern for an image display screen. The image display screen is perforated with the spatial distribution of perforations forming the semi-random pattern. Image rendering light is emitted by a light projector toward the image display screen mounted in an image rendering environment. The image display screen reflects at least a portion of the image rendering light emitted from the light projector toward a viewer.

[0035] Example embodiments described herein relate to an image display screen configured to reflect at least a portion of image rendering light emitted from a light projector toward a viewer, the image display screen including a spatial distribution of perforations forming a semi-random pattern to reduce moire patterns in an image rendering operation.

[0036] In embodiments, the image display screen includes a plurality of webs connected along one or more seam edges. In embodiments, the spatial distribution of perforations on the image display screen tends to become or switch from a semi-random hole pattern to a regular hole pattern near the one or more seam edges.

[0037] Example embodiments described herein relate to a method of manufacturing an image display screen, the method comprising: applying one or more perforation pattern methods to generate a spatial distribution of perforations that forms a semi-random pattern for the image display screen to reduce a Moire pattern in an image rendering operation; perforating the image display screen with the spatial distribution of perforations that forms the semi-random pattern; and providing a plurality of meshes connected along one or more seam edges of the image display screen. The spatial distribution of perforations on the image display screen tends to become a regular aperture pattern or switch from the semi-random pattern towards the regular aperture pattern along the one or more seam edges.

[0038] Various modifications to the preferred embodiments and generic principles described herein will be readily apparent to those skilled in the art. Thus, the 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.

[0039] 2. Regular aperture pattern

[0040] The strength and visibility of a Moire pattern generated by the interaction between the apertures on the screen and the visual representation of the pixels from the projector that are projected onto the screen and reflected from the screen depends on the relative spacing of the pixel pattern from the projector and the aperture pattern of the apertures, the size of the apertures, the amplitude (e.g., luminance, chrominance, etc.) of the pixel pattern from the projector. The worst Moire pattern can occur due to the spatial pitch of the aperture pattern forming a reasonable relationship with the spatial pitch of the pixel pattern. For example, a visually perceptible beat or Moire pattern is prone to occur when the aperture pattern has a spatial pitch that is similar to or a multiple of the spatial pitch of the pixel pattern.

[0041] Methods for reducing or preventing a Moire pattern can be referred to as de-Moire methods. One example de-Moire method is to de-focus the projection lens in the projector. This method can reduce the Moire pattern, but there is a risk of unnecessarily reducing the overall resolution of the image. When the lens is de-focused, the modulation transfer function (MTF) of the lens can change significantly in a device or design dependent / sensitive manner. While it is desirable for the de-focusing to only affect relatively high spatial frequencies (e.g., in or towards the upper portion of the full spatial frequencies that can be perceived by human vision), it can also affect relatively low spatial frequencies (e.g., in or towards the lower portion of the full spatial frequencies that can be perceived by human vision), depending on the projection lens design. For example, the relatively low spatial frequencies in the visual representation of the pixels in the projected image can sometimes be affected by such a de-Moire method.

[0042] In practice, it can be difficult to achieve the proper amount of de-focus in the projection lens while also trying to achieve a balance between de-mozaicing and de-focusing. A theater or cinema can be operated by multiple service technicians. Refocusing or de-focusing the projection lens can be one of the first things a service technician does before performing an operation task for the theater or cinema. The technician can not be familiar with the mozaic pattern issue, previous adjustments to reduce the issue, or the impact of the previous adjustments on the mozaic pattern issue and the resolution of the projected image. As a result, the technician is less likely to determine whether the proper amount of refocusing or de-focusing has been performed or is to be performed. The technician is also less likely to determine whether the refocusing or de-focusing that has been performed or is to be performed is to reduce the mozaic pattern issue or exacerbate the mozaic pattern issue.

[0043] Another example de-mozaicing method is to use a modified fixed aperture pattern (such as a digital aperture pattern (e.g., Harkness et al.)) to reduce the mozaic pattern.

[0044] Figure 1A An example modified fixed aperture pattern is illustrated represented in a two-dimensional space having vertical and horizontal spatial dimensions. The modified aperture pattern includes a two-dimensional array of apertures, each of the apertures represented by a solid black circle in Figure 1A Unlike a standard square or rectangular aperture pattern, the modified aperture pattern has alternating (aperture) rows that have a 1 / 2 aperture spatial offset compared to adjacent (aperture) rows. Likewise, the modified aperture pattern has alternating (aperture) columns that have a 1 / 2 aperture spatial offset compared to adjacent (aperture) columns. The 1 / 2 aperture spatial offset for the alternating (aperture) rows can be different than the 1 / 2 aperture spatial offset for the alternating (aperture) columns, but is not required to be.

[0045] Figure 1B An example square pixel pattern is illustrated superimposed with the modified fixed aperture pattern (e.g., in Figure 1A The square pixel pattern includes a two-dimensional array of pixels, each of the pixels represented by a white square in Figure 1B The apertures along the (aperture) columns in the modified aperture pattern are represented by solid black circles in Figure 1B which can be different than the Figure 1AThe modified fixed aperture pattern illustrated in FIG. 1 1 1 can still be prone to generating moire patterns.

[0046] Figure 1A And Figure 1B The modified fixed aperture pattern illustrated in FIG. 1 1 1 can still be prone to generating moire patterns. Figure 1C An example moire pattern is illustrated, which can be generated in a movie theater, for example, as Figure 1B The visual representation of the pixels in the pixel pattern illustrated in FIG. 1 1 1 includes a spatial frequency that has a reasonable relationship with the spatial frequency of the modified fixed aperture pattern when generated. When the spatial frequency of the pixel pattern or the visual representation of the pixels is similar to or a multiple of the spatial frequency of the aperture pattern of Figure 1A Or Figure 1B The moire pattern illustrated in FIG. 1 1 1 can be particularly noticeable or worst when the spatial frequency of the pixel pattern or the visual representation of the pixels is similar to or a multiple of the spatial frequency of the aperture pattern of Figure 1C

[0047] As used herein, the visual representation of a pixel can refer to the color, brightness, and / or chroma of the pixel as rendered on a screen. The visual representation of a pixel can be set based on the pixel value of the pixel received in the image data in a movie / image / video display operation.

[0048] Despite the improvements over the standard square or rectangular aperture pattern, the modified fixed aperture pattern can not sufficiently reduce or eliminate the moire pattern problem in a movie theater, cinema, or the like, for example.

[0049] 3. Semi-random aperture pattern

[0050] Under the techniques as described herein, the aperture locations on a screen or image display (e.g., an image display, a 60-foot movie theater screen, or the like) can be generated or implemented in a semi-random manner such that no moire pattern is generated or the moire pattern is minimized on the screen in an image rendering operation.

[0051] Figure 2A An example semi-random aperture pattern of perforations formed on a screen or image display is illustrated, which is represented in a two-dimensional space having vertical and horizontal spatial dimensions. The semi-random aperture pattern includes a two-dimensional (semi-random) spatial distribution of apertures, each of which is represented by Figure 2A ​a solid black circle is logically represented. The perforations as actually drilled or implemented on the screen as described herein can have any of a variety of closed shapes including, but not limited to, circular, oblong, polygonal, irregular, etc. In some operational scenarios, the perforations can be circular in shape and have a particular size, dimension, or diameter that is selected to be below the spatial resolution (or angular resolution) of a (human) viewer in the venue that is outside of a particular viewing distance. Image display operations in the venue are performed with one or more projectors to project 2D or 3D images onto a screen or image display that reflects at least a portion of the incident light toward the viewer in order to render an image visible to the viewer.

[0052] Unlike the aperture patterns under other methods (e.g., standard square / rectangular aperture pattern, modified aperture pattern, etc.), the semi-random aperture pattern of Figure 2A includes no visually discernible regular pattern (e.g., cross-hair pattern, etc.) but presents a uniform perforation to a (human) viewer at a distance far enough.

[0053] As used herein, "uniform" can refer to the perforation density on the screen being uniform (e.g., within a 0.1%, 1%, 2%, or another percentage of tolerance, etc.). Additionally, optionally, or alternatively, "uniform" can refer to the total number of perforations per unit area of the screen being uniform. Here, the unit area for measuring uniformity can be: comparable to an area distinguishable by the human eye (e.g., denoted with a human visual system or HVS, etc.); less than an area distinguishable by the human eye; etc.

[0054] A regular pattern as described herein can refer to a pattern formed by repeating a constant spatial offset. Example regular patterns can include, but are not necessarily limited to, any of the following: cross-hair pattern, square or rectangular pattern, matrix pattern, diagonal pattern, coaxial pattern, combinations of regular patterns with or without offset, etc.

[0055] A visually discernible regular pattern can refer to a regular pattern (or regular pattern portion) that is visibly discernible within the spatial resolution capability of the human visual system (e.g., within retinal acuity, within foveal acuity, etc.) in size, dimension, and / or repetition.

[0056] Figure 2B illustrates superimposed with a semi-random aperture pattern (e.g., in Figure 2AA medium-sized example of a square pixel pattern. As previously noted, a square pixel pattern comprises a two-dimensional array of pixels, each of which is represented by a white square in the square pixel pattern. A semi-random eyelet pattern has individual spatial displacements for each eyelet (solid black circle) with respect to variations in the pixels within the pixel pattern (e.g., white squares in which the eyelet is embedded or at least partially overlaps).

[0057] like Figure 2A and Figure 2B The semi-random perforation pattern shown in the middle diagram can be used to eliminate or greatly reduce visual artifacts associated with moiré patterns. Figure 2C The diagram illustrates how it can be used in, for example. Figure 2B The image shows an example (worst-case) moiré pattern generated when the pixel visual representation of the pixel pattern is shown. A reasonable relationship for the moiré pattern is difficult to form a sufficiently clear range between the spatial frequencies in the visual representation of the pixel pattern and the spatial frequencies of the semi-random perforation pattern to generate visual artifacts associated with the moiré pattern, provided that the perforations in the semi-random perforation pattern are irregularly or visually randomly distributed. Therefore, as... Figure 2C The moiré pattern shown in the image may not exist or may be far less than the actual moiré pattern. Figure 1C The moiré pattern is severe and therefore may be invisible to the viewer or far less noticeable to the viewer in actual image rendering operations.

[0058] One or more hole position generation methods can be used individually or in combination with systems as described herein to generate semi-random patterns of hole positions on a screen or image display. In some operational scenarios, the hole position generation method can be any combination of halftone methods implementing one or more halftone techniques, including but not limited to: dithering, void-and-cluster, tessellation, stochastic screening, direct binary search (DBS), error diffusion, frequency modulation (FM), etc.

[0059] 4. System Configuration

[0060] Figure 3AAn example cinema 300 is illustrated. Two-dimensional and / or three-dimensional image / video content can be rendered using one or more projectors (e.g., 316, a digital laser projector, or a DLP, etc.) deployed in the cinema (300). Projectors as described herein (e.g., 316, etc.) may include light engines, prisms, optics, digital micromirror devices, or DMDs, etc., to generate light and project it onto a screen (e.g., an image display, etc.) 314. Light projected from the projector (316) is reflected from the screen (314) toward one or more viewers in a viewer area (e.g., an audience area, a seating area, a designated area, etc.) 312. One or more speakers 318 may be positioned or located behind the screen (314). These speakers (318) emit sound depicting sounds from audio sources (e.g., people, musical instruments, objects, etc.) located within and / or outside the visual scene depicted in the image rendered by the light projected from the projector (316) onto the screen (314). In various embodiments, the screen (314) may be made of a single mesh or multiple meshes.

[0061] Figure 3B The illustration shows an example screen (e.g., Figure 3A 314, an image display, etc.), the screen is joined, stitched, and / or welded together with multiple meshes (e.g., 302-1 to 302-4, etc.). Adjacent meshes (e.g., 302-1 and 302-2, 302-2 and 302-3, etc.) may be physically connected along seams (e.g., 306, etc.). Each mesh (e.g., obtained or cut from a roll of a particular screen material, with a width equal to one yard of the roll of the particular screen material, etc.) may be logically partitioned to form multiple segments (e.g., 310, etc.) in the overall reference pattern 304. For illustrative purposes only, the reference pattern (304) may be a rectangular grid pattern. The reference pattern (304) may be logical rather than physical, and therefore may not possess visual features visible to a viewer. The reference pattern (304) or segments therein (e.g., 310, etc.) may be used as starting points or initial conditions for generating eyelet positions in a semi-random pattern.

[0062] like Figure 3B As illustrated in the diagram, each of some or all of the multiple segments (e.g., 310, etc.) can be further logically (e.g., invisibly, etc.) partitioned into candidate locations (e.g., 308, etc.), some of which can be selected or identified as locations for placing or implementing perforations. Perforation locations exhibiting a semi-random pattern can be selected from a set of candidate locations (e.g., 308, etc.) of the multiple segments (e.g., 310, etc.) in the reference pattern (304) using a perforation generation method as described herein.

[0063] The location of a segment (e.g., 310, etc.) in the reference pattern (304) can be specified or defined with respect to the reference pattern (304) (e.g., with an array index, with a coordinate value, with an index value, with a row and column value, etc.) as the upper left grid point or vertex of the reference pattern (304). Likewise, the aperture location can be specified or defined with respect to the grid point or vertex of the regular grid pattern (304) (e.g., with an array index, with a coordinate value, with an index value, with a row and column value, etc.) as the upper left grid point or vertex of the segment in which the aperture location resides.

[0064] For example, the plurality of candidate locations (e.g., 308, etc.) can reside in a segment of the reference pattern (304). The segment can be one of a plurality of segments (e.g., 310, etc.) forming a two-dimensional (2D) segment array as illustrated in Figure 3B For example, the plurality of candidate locations (e.g., 308, etc.) can reside in a segment of the reference pattern (304). The segment can be one of a plurality of segments (e.g., 310, etc.) forming a two-dimensional (2D) segment array as illustrated in

[0065] For example, the plurality of candidate locations (e.g., 308, etc.) can reside in a segment of the reference pattern (304). The segment can be one of a plurality of segments (e.g., 310, etc.) forming a two-dimensional (2D) segment array as illustrated in Figure 3B For example, the plurality of candidate locations (e.g., 308, etc.) can reside in a segment of the reference pattern (304). The segment can be one of a plurality of segments (e.g., 310, etc.) forming a two-dimensional (2D) segment array as illustrated in

[0066] The aperture locations can be generated using the aperture generation method as described herein. The aperture locations can be selected from some or all of the candidate locations in some or all of the segments of the reference pattern (304) as a subset (e.g., an appropriate, etc.) of the candidate locations in the reference pattern (304) such that the aperture locations are placed with varying individual spatial displacements with respect to the segments (in the reference pattern (304)) in which the aperture locations reside in order to form a semi-random pattern that is different from the reference pattern (304).

[0067] In some operational scenarios, the hole generation methods as described herein can implement or utilize (e.g., iterative, recursive, etc.) halftoning techniques (e.g., Ulichney's void and cluster initial pattern (VACip) technique) to generate the semi-random pattern. The halftoning techniques can be applied to the entire screen, applied in its entirety or applied individually to a portion thereof (e.g., a mesh, a single fabric mesh or a set of contiguous segments on multiple meshes, etc.). These techniques can be used to produce a spatially random pattern (e.g., as compared to the reference pattern (304), as compared to a regular pattern, etc.) from the candidate locations of the screen or image display. Additionally, optionally or alternatively, these techniques can be implemented to avoid or significantly reduce the non-uniform low frequency pattern that can be observed on the screen.

[0068] The semi-random hole pattern generated with the halftoning techniques provides or maintains uniformity in hole density (on the screen or image display), total number of holes per unit area (on the screen or image display) commensurate with or smaller than the area that can be spatially resolved by the HVS, etc. The image rendering operations on the screen or image display with the semi-random hole pattern thus generated do not produce or produce very few moire patterns. Additionally, the uniform hole density and corresponding aggregated hole area on a relatively small scale (e.g., commensurate with or smaller than the area that can be spatially resolved by the viewer's vision, etc.) allows the sound from the speakers behind the screen to pass through without or with only very little impedance.

[0069] The hole tool used to drill, punch or otherwise form perforations on the screen or its mesh can be driven with hole position data specifying the hole positions generated as described herein.

[0070] In some operational scenarios, the hole generation methods as described herein can implement a noise generation technique to generate the semi-random pattern. The noise can be generated with the noise generation technique and used to modify a reference hole pattern (which can be the same as or can be different from the reference pattern of Figure 3B The reference hole pattern can be the same as a commercially available digital hole pattern or another standard hole pattern (e.g., a regular hole mesh (or regular pattern hole mesh)) that can be susceptible to generating moire patterns in the image rendering operations.

[0071] More specifically, the noise can be used to generate varying spatial displacements for different positions (e.g., expressed in spatial dimensions x and y, etc.) of the mesh points (or vertices) in the regular hole mesh. The noise can be high frequency noise that has enough amount to reduce or avoid moire patterns but not large enough to increase the non-uniformity of the perforation distribution on the screen.

[0072] In some embodiments, the noise can be generated with a high-pass filtering (e.g., with a two-dimensional filter, with a kernel separable filter, etc.) with a uniform amplitude distribution (e.g., by frequency of passing, by maximum allowable distance from a reference regular grid point or vertex, by maximum allowable distance from a reference regular grid line, etc.) to reduce non-uniformity of the semi-random pattern on the screen when viewed at a certain distance (low-pass filtered by the human eye). The amplitudes of the noise along different spatial directions can be different or the same. For example, the amplitudes of the noise along the spatial axis x can be set to be different or the same from the amplitudes of the noise. Additionally, optionally, or alternatively, the angles of the spatial displacements as described herein can be generated or derived from the noise.

[0073] Filtering operation parameters (e.g., cutoff frequency, amplitude, filter coefficients, number of filter taps, etc.) for the high-pass filtering can be set, selected, and / or determined through computer-aided modeling (e.g., MATLAB simulation, etc.) or empirical studies.

[0074] For example, the filtering operation parameters can be varied in range, value, etc. to determine whether the semi-random pattern generated according to the varied filtering operation parameters interacts with the visual content rendered on the screen to generate a visually noticeable moire pattern. At the same time, other non-filtering operation parameters such as the type and / or size of the screen, the viewing distance, the number of meshes, the type of meshes, the image resolution (e.g., 4K, 8K, etc.), the manufacturer, the type and / or model of the projector, the density, size, and / or shape of the perforations, the number and type of speakers, the focus and / or defocus of the projection lens, etc. can be fixed or varied while the values of the filtering operation parameters are varied and validated to determine or select the optimal values of the filtering operation parameters from the varied and validated values. The optimal values of the filtering operation parameters can generate sufficient noise to avoid or reduce the moire pattern in the test images or real images used in the optimization operation and to avoid or reduce any non-uniformity that can be introduced to the spatial locations of the perforations by the noise injection. Thus, the spatial variations in the spatial locations of the perforations and / or the noise can be generated and distributed on the screen or image display in a semi-random manner (e.g., with a halftoning or noise injection algorithm with optimized operation parameter values, etc.) as opposed to a truly random manner.

[0075] The semi-random aperture pattern generated with the noise generation / injection technique provides or maintains uniformity in terms of aperture density (on the screen or image display), total number of apertures per unit area (on the screen or image display) that is comparable to or smaller than an area that can be spatially resolved by the HVS, and the like. Image rendering operations on a screen or image display with a semi-random aperture pattern thus generated do not produce or produce very few moire patterns. In addition, the uniform aperture density and corresponding aggregated aperture area on a relatively small scale (e.g., a unit area that is comparable to or smaller than an area that can be spatially resolved by a viewer’s vision, and the like) allow sound from speakers behind the screen to pass through without or with only very little impedance.

[0076] Aperture tools for drilling, punching, or otherwise forming perforations on a screen or its mesh can be driven with aperture position data that specifies aperture positions generated by the noise generation / injection technique as described herein.

[0077] In some operational scenarios, the amount of noise representing spatial displacement relative to regular grid points (or vertices) in a regular aperture pattern can be controlled to be significantly smaller (e.g., 1 / 8, 1 / 4, 1 / 2, and the like) than the aperture pitch in the regular aperture pattern. This can be used to reduce or avoid the presence of aperture (hole) positions at the mesh edges.

[0078] In operational scenarios where aperture positions are derived based on a reference grid or pattern such as a reference aperture grid, the cutting and joining for combining, seaming, stitching, and / or welding the mesh of the entire screen (or image display) can be performed based on the grid positions represented in the reference grid or pattern without introducing a DC offset (e.g., a pitch offset along a seam edge of two joined meshes by a constant offset amount, and the like) that affects the uniformity of the overall regular pattern of the screen or the uniformity of the screen semi-random pattern generated from the regular pattern of the screen by the noise or varying spatial displacement. Thus, the screen material such as a mesh can be seamed, stitched, and / or welded without producing visible artifacts.

[0079] In some operational scenarios, the noise generation technique used to generate the semi-random perforation pattern can be modified to reduce the amplitude of the noise when a perforation is near an edge of the web, such that the position of the perforation tends to become a regular perforation pattern toward the edge of the web (from which the semi-random perforation is generated by a spatial displacement corresponding to the variation of the noise). An extreme example can be to switch to the (original) regular perforation grid only toward the edge of the web. In other words, the spatial distribution of the perforations on the image display screen transitions (continuously) from the semi-random perforation pattern to the regular perforation pattern toward the edge of the web (e.g., at the seam edge). Any of these modifications can be used to prevent the creation of visible artifacts at the edge of the web when connected with an adjacent web, as the edge in the web and in its adjacent web converge to, tend to become, and / or switch to the same (original pre-modified) regular perforation grid.

[0080] Likewise, in some operational scenarios, the halftoning technique used to generate the semi-random perforation pattern can be modified to reduce the strength of the halftoning (or dithering) operation when near an edge of the web, such that the position of the perforation tends to become a regular perforation pattern toward the edge of the web (from which the semi-random perforation is generated by halftoning or dithering). In other words, the spatial distribution of the perforations on the image display screen transitions (continuously) from the semi-random perforation pattern to the regular perforation pattern toward the edge of the web (e.g., at the seam edge). These modifications can be used to prevent the creation of visible artifacts at the edge of the web.

[0081] In some operational scenarios, the halftoning technique can result in incomplete perforations (e.g., half-perforations, etc.) along the edges of the webs in the plurality of webs that are seamed, stitched, and / or welded into a screen. When filling voids with perforations or avoiding congestion of too many perforations in existing clusters, the halftoning algorithm can use a composition such as a circle / sphere to cover adjacent zones. For example, the halftoning algorithm can operate to help place perforations in voids and discourage placing perforations in clusters that extend through multiple adjacent zones or regions of the screen. Thus, some perforations can be placed by the halftoning algorithm along the edges of two adjacent webs. In practice, the half-perforations or incomplete perforations on two adjacent webs can not perfectly match, resulting in half-perforations or incomplete perforations that are (potentially, visibly, etc.) apparent along the edges of the webs. In some operational scenarios, the injection or generation of noise such as high frequency noise into the position of the perforations can be limited such that the semi-random pattern of perforations as described herein in a screen are located in a single web without leaving half-perforations or incomplete perforations along the edges of the webs on the screen.

[0082] For purposes of illustration only, it has been described that the screen can have a rectangular shape. However, it should be noted that in various embodiments, the semi-random perforation pattern can be implemented in screens having a rectangular or non-rectangular shape, regular or irregular shape, curved or flat shape, etc.

[0083] For example, under other approaches, the moire pattern problem can become apparent and noticeable in certain areas of a curved or hemispherical image display as the likelihood of a reasonable relationship (e.g., similarity, multiple, etc.) between the spatial frequency response of the regular aperture pattern and the spatial frequency in the visual representation of the pixels is relatively high.

[0084] In contrast, under the techniques described herein, a semi-random aperture pattern can be implemented with a curved or hemispherical image display in which the pixels can not be formed by square screen gates (or black bars around the pixels in white squares) as Figure 2B illustrated in FIG. 1 but by other shapes having constant or size varying depending on the location of the pixels on the curved or hemispherical image display. Such semi-random pattern can be used with a curved or hemispherical image display to reduce or prevent the moire pattern problem, provide uniformity of the apertures for sound propagation, reduce or prevent visual artifacts along the edges / seams or elsewhere on the display.

[0085] As described herein, the screen or image display can use a wide variety of materials (e.g., mesh, etc.). Example materials can include, but are not necessarily limited to, only any of the following: synthetic material, plastic or vinyl material, washable material, seamed material, stitched material, welded material, material connected with flat or invisible seams, coated grain screen material, polarized screen material, laser projection screen material, woven material, non-woven material, random woven material or material with a random woven pattern, natural or non-natural material, etc.

[0086] The pixel size of a screen (e.g., 60-ft screen, 50-ft screen, 10-ft screen, etc.) (or the size of the pixels such as the white squares of FIG. 1, etc.) can depend in whole or in part on the image resolution of the image rendered on the screen and the size of the screen. Figure 2B The aperture size and density can depend in whole or in part on the audio configuration (e.g., speaker configuration, etc.) deployed with the screen (e.g., in Figure 3AThe density and size of the perforations on the screen can be specifically chosen to be large enough to allow sound to propagate from the loudspeakers behind the screen to the viewer / listener and small enough that the perforations are not visually apparent or perceptible to the viewer / listener. In some operational scenarios, the pixels on the screen as described herein can have a finer spatial resolution than the perforations on the screen; for example, the pixel size can be larger than the average spacing or distance between or among the perforations. In some operational scenarios, the pixels on the screen as described herein can have a coarser spatial resolution than the perforations on the screen; for example, the pixel size can be smaller than the average spacing or distance between or among the perforations. In some operational scenarios, the pixels on the screen as described herein can have a spatial resolution comparable to that of the perforations on the screen.

[0087] For purposes of illustration only, it has been described that the semi-random perforation pattern can be generated by a halftoning method or a noise generation / injection method. It should be noted that other methods, such as a combination of halftoning and noise generation methods, etc., can be used to generate the semi-random perforation pattern in various embodiments. For example, the noise generation / injection method can be applied from a pattern generated by the halftoning method instead of a regular grid pattern. Additionally, optionally, or alternatively, the halftoning method can be applied from a pattern generated by the noise generation / injection method.

[0088] 5. Example process flow

[0089] Figure 4An example process flow is illustrated in accordance with example embodiments of the present application. In some example embodiments, a system comprising one or more of a computing device or component, a hole tool, a drill tool, a seam tool, a weld tool, a stitch tool, a screen material assembly tool, an image processing system, an image projector, an audio system, etc. can perform the process flow. In block 402, the system applies one or more hole pattern methods to generate a spatial distribution of holes that forms a semi-random pattern for an image display screen to reduce moire patterns. A semi-random pattern represents a spatially random hole pattern that is free of a relatively low frequency pattern that is prone to generating moire patterns in image rendering operations. As used herein, "low frequency," "relatively low frequency," "low spatial frequency," "relatively low spatial frequency," and the like refer to spatial frequencies in or toward a lower portion of a full spatial frequency spectrum that is visually perceptible by the HVS. Alternatively or equally, "low frequency," "relatively low frequency," "low spatial frequency," "relatively low spatial frequency," and the like can refer to spatial frequencies (e.g., in a semi-random hole pattern, etc.) that form a reasonable relationship (e.g., comparable to or a multiple of spatial frequencies in image features of a rendered image) to thereby generate moire patterns in image rendering operations. Conversely, "high frequency," "relatively high frequency," "high spatial frequency," "relatively high spatial frequency," and the like refer to spatial frequencies in or toward an upper portion of a full spatial frequency spectrum that is visually perceptible by the HVS. Alternatively or equally, "high frequency," "relatively high frequency," "high spatial frequency," "relatively high spatial frequency," and the like can refer to spatial frequencies (e.g., in a semi-random hole pattern, etc.) that do not form a reasonable relationship (e.g., comparable to or a multiple of spatial frequencies in image features of a rendered image) to thereby avoid or reduce moire patterns in image rendering operations.

[0090] In block 404, the system perforates the image display screen with the spatial distribution of holes that forms the semi-random pattern. In block 406, the system emits image rendering light through a light projector toward the image display screen mounted in an image rendering environment.

[0091] In block 408, the system reflects at least a portion of the image rendering light emitted from the light projector through the image display screen toward a viewer.

[0092] Without blocks 406 and 408, blocks 402 and 406 represent steps of a method of manufacturing an image display screen. Such a method of manufacturing an image display screen can further include Figure 4 an additional step (not shown in FIG. 4) of providing a plurality of webs connected along one or more seam edges of the image display screen. The spatial distribution of holes on the image display screen tends to become a regular hole pattern or switch from a semi-random hole pattern toward the one or more seam edges.

[0093] In an embodiment, an image display system comprises: an image display screen comprising a spatial distribution of perforations forming a semi-random pattern; a light projector emitting image rendering light toward the image display screen. The image display screen reflects at least a portion of the image rendering light emitted from the light projector toward a viewer.

[0094] In an embodiment, the semi-random pattern is a two-dimensional pattern generated by applying a halftoning technique over one or more regions of the image display screen.

[0095] In an embodiment, the semi-random pattern is a two-dimensional pattern generated by applying a noise injection technique over one or more regions of the image display screen.

[0096] In an embodiment, the semi-random pattern is a two-dimensional pattern generated by applying a combination of two or more semi-random pattern generation techniques over one or more regions of the image display screen; the combination of two or more semi-random pattern generation techniques comprises one or more of: a halftoning technique, a noise injection technique, a dithering technique, or another pattern generation technique.

[0097] In an embodiment, the viewer is in front of the image display screen; wherein the image display system is in operative communication with a set of audio speakers behind the image display screen; the set of audio speakers simultaneously generate sound that propagates through the perforations of the image display screen toward the viewer.

[0098] In an embodiment, the image display system operates in one of: a cinema, a theater, an amusement park, an exhibition hall, a home environment, a bar, a club, or another venue.

[0099] In an embodiment, the viewer is located outside of a designated viewing distance.

[0100] In an embodiment, the spatial distribution of perforations on the image display screen is uniform in area of a size that is visually resolvable by a viewer located at a designated viewing distance from the image display screen.

[0101] In an embodiment, the semi-random pattern is less susceptible to generating a moire pattern in an image rendering operation than a regular hole pattern.

[0102] In an embodiment, the image display screen comprises a plurality of slits connected along one or more slit edges.

[0103] In an embodiment, the spatial distribution of perforations on the image display screen tends to become a regular hole pattern at one or more slit edges.

[0104] In an embodiment, the spatial distribution of perforations on the image display screen switches to a regular hole pattern at one or more slit edges.

[0105] In various example embodiments, an apparatus, a system, a device, or one or more other computing devices perform any of the aforementioned methods, or portions thereof, as described. In embodiments, a non-transitory computer-readable storage medium stores software instructions which, when executed by one or more processors, cause performance of a method as described herein.

[0106] Note that although individual embodiments are discussed herein, any combination of the embodiments and / or portions of embodiments discussed herein can be combined to form further embodiments.

[0107] 6. Implementation Mechanism - Hardware Overview

[0108] According to one embodiment, the techniques described herein are implemented by one or more special-purpose computing devices. The special-purpose computing devices can be hard-wired to perform the techniques, or can include digital electronic devices such as one or more application-specific integrated circuits (ASICs) or field programmable gate arrays (FPGAs) that are persistently programmed to perform the techniques, or can include one or more general purpose hardware processors programmed to perform the techniques pursuant to program instructions in firmware, memory, other storage, or a combination. Such special-purpose computing devices can also combine custom hard-wired logic, ASICs, or FPGAs with custom programming to accomplish the techniques. The special-purpose computing devices can be desktop computer systems, portable computer systems, handheld devices, networking devices, or any other device that incorporates hard-wired and / or program logic to implement the techniques.

[0109] For example, Figure 5 FIG. 5 is a block diagram that illustrates a computer system 500 upon which an example embodiment of the application can be implemented. The 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. The hardware processor 504 can be, for example, a general purpose microprocessor.

[0110] The 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 to be executed by processor 504. Main memory 506 also can be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 504. Such instructions can be stored in one or more non-transitory computer readable storage media, when stored in a processor- accessible memory, such instructions render the computer system 500 into a special-purpose machine that implements the techniques described herein.

[0111] The 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.

[0112] Storage devices 510, such as disks or CD-ROMs, solid state RAM, etc., are provided and coupled to bus 502 for storing information and instructions.

[0113] Computer system 500 can be coupled via bus 502 to a display 512, such as a liquid crystal display, for displaying information to a computer user. Input devices 514, including alphanumeric and other keys, are coupled to bus 502 for communicating information and command selections to processor 504. Another type of user input device is cursor control 516, such as a mouse, trackball, or cursor direction keys, for communicating direction information and command selections to processor 504 and for

[0114] Computer system 500 can implement the techniques described herein using customized hard-wired logic, one or more ASICs or FPGAs, firmware and / or program logic which in combination with the computer system causes or programs computer system 500 to be a special-purpose machine. According to one embodiment, the techniques

[0115] The term "storage media" as used herein refers to any non-transitory media that store data and / or instructions that cause a machine to operate in a specific fashion. Such storage media can comprise non-volatile media and / or volatile media. Non-volatile media includes, for example, optical or magnetic disks, such as storage device 510. Volatile media includes dynamic memory, such as main memory 506. Common forms of storage media include, for example, a floppy disk, a flexible disk, hard disk, solid state drive, magnetic tape, or any other magnetic data storage medium, a CD-ROM, any other optical data storage medium, any physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, NVRAM, any other memory chip or cartridge.

[0116] Storage media differs from, and is not to be confused with, transmission media. Transmission media participate in carrying information between storage media. For example, coaxial cables, copper wires and fiber optic cables are transmission media. Transmission media can also take the form of acoustic or light waves, such as those generated during radio frequency (RF) and infrared (IR) data communications.

[0117] Various forms of media can be involved in carrying one or more sequences of one or more instructions to processor 504 for execution. For example, the instructions can initially be carried on a magnetic disk or solid state drive of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to computer system 500 can receive the data on the telephone line and use an infra-red transmitter to convert the data to an infra-red signal. An infra-red detector can receive the data carried in the infra-red signal and appropriate circuitry can place the data on bus 502. Bus 502 carries the data to memory 506, from which processor 504 retrieves and executes the instructions. The instructions received by memory 506 can optionally be stored on storage device 510 either before or after execution by processor 504.

[0118] Computer system 500 also includes a communication interface 518 coupled to bus 502. Communication interface 518 provides a two-way data communication coupling to a network link 520 that is connected to a local network 522. For example, communication interface 518 can be an integrated services digital network (ISDN) card, cable modem, satellite modem, or a modem to provide a data communication connection to a corresponding type of telephone line. As another example, communication interface 518 can be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links can also be implemented. In any such implementation, communication interface 518 sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information.

[0119] Network link 520 typically provides data communication through one or more networks to other data devices. For example, network link 520 can provide a connection through 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 and through communication interface 518, which carry the digital data to and from computer system 500, are example forms of transmission media.

[0120] 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.

[0121] The received code can be executed by processor 504 as it is received, and / or stored in storage device 510, or other non-volatile storage for later execution.

[0122] 7. Equivalents, Expansions, Alternatives, and Further

[0123] In the foregoing specification, example embodiments of the application have been described with reference to a number of specific details that can vary depending on implementation. Thus, the sole and exclusive indicator of what is the application, and is intended by the applicants to be the scope of the application, is the set of claims issued by the U.S. Patent Office, any corrections thereto, any subsequent issuance of reissued patents, any extensions thereof, and any combinations of the foregoing. Any definitions of the terms per se contained herein are expressly incorporated herein by reference in their entirety. Therefore, no limitation is placed on the scope of the claims, which encompass substitutions, equivalents, and alternatives that are apparent in light of the specification or that are otherwise known in the art to which the application pertains. The specification and drawings should therefore be regarded as illustrative in nature and not as restrictive.

[0124] Aspects of some embodiments include the following enumerated example embodiments (EEEs):

[0125] EEE 1. An image display system, comprising:

[0126] an image display screen comprising a spatial distribution of perforations forming a semi-random pattern to reduce a moire pattern in an image rendering operation;

[0127] wherein the semi-random pattern represents a spatially random pattern of perforations free of a relative low frequency pattern that is prone to generate the moire pattern in the image rendering operation;

[0128] a light projector configured to emit image rendering light toward the image display screen;

[0129] wherein the image display screen is configured to reflect at least a portion of the image rendering light emitted from the light projector toward a viewer.

[0130] EEE 2. The image display system of EEE 1, wherein the semi-random pattern is a two-dimensional pattern generated by applying a halftone technique over one or more regions of the image display screen.

[0131] EEE 3. The image display system of EEE 1, wherein the semi-random pattern is a two-dimensional pattern generated by applying a noise injection technique over one or more regions of the image display screen.

[0132] EEE 4. The image display system of EEE 1, wherein the semi-random pattern is a two-dimensional pattern generated by applying a combination of two or more semi-random pattern generation techniques over one or more regions of the image display screen; wherein the combination of two or more semi-random pattern generation techniques includes one or more of: a halftone technique, a noise injection technique, a dithering technique, or another pattern generation technique.

[0133] EEE 5. The image display system of any one of EEEs 1-4, wherein the viewer is in front of the image display screen; wherein the image display system is configured to operate in tandem with a set of audio speakers behind the image display screen; wherein the set of audio speakers is configured to simultaneously generate sound that propagates through the perforations of the image display screen towards the viewer.

[0134] EEE 6. The image display system of any one of EEEs 1-5, wherein the image display system operates in one of: a cinema, a theater, an amusement park, an exhibition hall, a home environment, a bar, a club, or another venue.

[0135] EEE 7. The image display system of any one of EEEs 1-6, wherein the viewer is located beyond a designated viewing distance.

[0136] EEE 8. The image display system of any one of EEEs 1-7, wherein the spatial distribution of the perforations on the image display screen is uniform for an area of a size that is visually resolvable by the viewer located at a designated viewing distance from the image display screen.

[0137] EEE 9. The image display system of any one of EEEs 1-8, wherein the semi-random pattern is less susceptible to generating a moire pattern in an image rendering operation than a regular hole pattern.

[0138] EEE 10. The image display system of any one of EEEs 1-9, wherein the image display screen comprises a plurality of meshes connected along one or more seam edges.

[0139] EEE 11. The image display system of EEE 10, wherein the spatial distribution of the perforations on the image display screen tends to become a regular hole pattern at the one or more seam edges.

[0140] EEE 12. The image display system of EEE 10, wherein the spatial distribution of perforations on the image display screen switches to a regular hole pattern at the edge of the one or more slits.

[0141] EEE 13. A method comprising:

[0142] applying one or more perforation pattern methods to generate a spatial distribution of perforations that forms a semi-random pattern for an image display screen to reduce a moire pattern in an image rendering operation;

[0143] wherein the semi-random pattern represents a spatially random hole pattern free of a relatively low frequency pattern that is prone to generate the moire pattern in the image rendering operation;

[0144] perforating the image display screen with the spatial distribution of perforations that forms the semi-random pattern;

[0145] emitting, by a light projector, image rendering light toward the image display screen mounted in an image rendering environment;

[0146] reflecting, by the image display screen, at least a portion of the image rendering light emitted from the light projector toward a viewer.

[0147] EEE 14. A non-transitory computer-readable storage medium storing software instructions that, when executed by one or more processors, cause performance of the method of EEE 13.

[0148] EEE 15. An apparatus comprising one or more processors and one or more storage media storing a set of instructions, which, when executed by one or more processors, cause performance of the method of EEE 13.

Claims

1. An image display screen, comprising: a spatial distribution of perforations forming a semi-random pattern to reduce moire patterns in image rendering operations, wherein the perforations in the semi-random pattern have varying individual spatial displacements with respect to pixels; wherein the image display screen is configured to reflect at least a portion of image rendering light emitted from a light projector toward a viewer; wherein the image display screen comprises a plurality of webs connected along one or more seam edges; and wherein the spatial distribution of perforations on the image display screen tends to change from the semi-random pattern to a regular hole pattern toward the one or more seam edges.

2. The image display screen of claim 1, wherein, the semi-random pattern is a two-dimensional pattern generated by applying a halftoning technique over one or more regions of the image display screen.

3. The image display screen of claim 1, wherein, the semi-random pattern is a two-dimensional pattern generated by applying a noise injection technique over one or more regions of the image display screen.

4. The image display screen of claim 1, wherein, the semi-random pattern is a two-dimensional pattern generated by applying a combination of two or more semi-random pattern generation techniques over one or more regions of the image display screen; wherein the combination of two or more semi-random pattern generation techniques comprises one or more of: a halftoning technique, a noise injection technique, a dithering technique, or another pattern generation technique.

5. The image display screen of any one of claims 1 to 4, wherein, the viewer is in front of the image display screen; wherein the image display screen is configured to operate in tandem with a set of audio speakers behind the image display screen; wherein the perforations of the image display screen are configured to allow sound generated by the set of audio speakers to propagate through the image display screen toward the viewer.

6. The image display screen of any one of claims 1 to 4, configured to operate in one of: a cinema, a theater, an amusement park, an exhibition hall, a home environment, a bar, a club, or another venue.

7. The image display screen of any one of claims 1 to 4, wherein, the viewer is located beyond a designated viewing distance from the image display screen.

8. The image display screen of any one of claims 1 to 4, wherein, the spatial distribution of perforations on the image display screen is uniform for an area of a size that is visually resolvable by the viewer located at the designated viewing distance from the image display screen.

9. The image display screen of any one of claims 1 to 4, wherein, the semi-random pattern is less prone to generate moire patterns in image rendering operations than a regular hole pattern.

10. A method of manufacturing an image display screen, the method comprising: applying one or more perforation pattern methods to generate a spatial distribution of perforations forming a semi-random pattern for the image display screen to reduce moire patterns in image rendering operations, wherein the perforations in the semi-random pattern have varying individual spatial displacements with respect to pixels; perforating the image display screen with the spatial distribution of perforations forming the semi-random pattern; providing a plurality of webs connected along one or more seam edges of the image display screen; wherein the spatial distribution of perforations on the image display screen tends to change from the semi-random pattern to a regular hole pattern toward the one or more seam edges.

11. The method of claim 10, wherein, The semi-random pattern is a two-dimensional pattern generated by applying a halftoning technique over one or more regions of the image display screen.

12. The method of claim 10, wherein, The semi-random pattern is a two-dimensional pattern generated by applying a noise injection technique over one or more regions of the image display screen.

13. The method of claim 10, wherein, The semi-random pattern is a two-dimensional pattern generated by applying a combination of two or more semi-random pattern generation techniques over one or more regions of the image display screen; wherein the combination of two or more semi-random pattern generation techniques includes one or more of: a halftoning technique, a noise injection technique, a dithering technique, or another pattern generation technique.

14. The method of any one of claims 10 to 13, wherein, A viewer is in front of the image display screen; wherein the image display screen is configured to operate in tandem with a set of audio speakers behind the image display screen; and wherein the perforations of the image display screen are configured to allow sound generated by the set of audio speakers to propagate through the image display screen towards the viewer.

15. The method of any one of claims 10 to 13, wherein, The image display screen operates in one of: a cinema, a theater, an amusement park, an exhibition hall, a home environment, a bar, a club, or another venue.

16. The method of any one of claims 10 to 13, wherein, A viewer is located beyond a designated viewing distance from the image display screen.

17. The method of any one of claims 10 to 13, wherein, The spatial distribution of the perforations on the image display screen is uniform for an area of a size that is visually resolvable by a viewer located at a designated viewing distance from the image display screen.

18. The method of any one of claims 10 to 13, wherein, The semi-random pattern is less susceptible to generating a moire pattern in image rendering operations than a regular hole pattern.

19. A non-transitory computer-readable storage medium storing software instructions that, when executed by one or more processors, cause performance of the method of any one of claims 10-18.

20. An image display apparatus comprising one or more processors and one or more storage media storing a set of instructions that, when executed by the one or more processors, cause performance of the method of any one of claims 10-18.

Images