Projection system and method using modular projection lens - Patents.com

Abstract

The projection lens system and method therefore includes a Fourier lens assembly having a first mounting portion and configured to form a Fourier transform of an object at an exit pupil of the Fourier lens assembly, a diaphragm configured to block a portion of incident light and located approximately at a Fourier transform plane, and a zoom lens assembly having a second mounting portion configured to be removably mounted to the first mounting portion.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 944,931, filed December 6, 2019, and U.S. Provisional Patent Application No. 63 / 047,456, filed July 2, 2020, which are incorporated herein by reference.

[0002] 1. Field of disclosure The present application generally relates to projection systems and methods of operating projection systems. [Background technology]

[0003] 2. Description of Related Technology Digital projection systems typically utilize a light source and an optical system to project an image onto a surface or screen. The optical system may include components such as mirrors, lenses, waveguides, optical fibers, beam splitters, diffusers, and spatial light modulators (SLMs). A projector's contrast indicates the projector's brightest output relative to its dimmest output. Contrast ratio is a quantitative measure of contrast and is defined as the ratio of the luminance of the projector's brightest output to the luminance of its dimmest output. This definition of contrast ratio is also known as the "static", "native", or "sequential" contrast ratio.

[0004] Some projection systems are based on SLMs that realize spatial amplitude modulation, such as digital micromirror device (DMD) chips. When a DMD chip is used as a light modulator, the projection display can create a high contrast ratio by taking advantage of the diffraction effect of the DMD. The contrast ratio in such a system can be based on various parameters, such as the specific combination of DMD pixel size, tilt angle, illumination angle, and illumination f / #. Other relevant elements in the design of a projection system include the projection lens, where the Fourier filter (aperture) is placed. The Fourier aperture blocks diffractive orders of the projection lens that can reduce the contrast of the image. Summary of the Invention [Problem to be solved by the invention]

[0005] Various aspects of the present disclosure relate to apparatus, systems, and methods for projection displays using high contrast projection architectures. [Means for solving the problem]

[0006] In one exemplary aspect of the present disclosure, a projection lens system is provided that includes a Fourier lens assembly having a first mounting portion configured to form a Fourier transform of an object at an exit pupil of the Fourier lens assembly, an aperture configured to block a portion of incident light and located approximately at the Fourier transform plane, and a zoom lens assembly having a second mounting portion configured to be removably mounted to the first mounting portion.

[0007] In another exemplary aspect of the present disclosure, a method of providing a projection lens system is provided, the method including: providing a Fourier lens assembly having a first mounting portion configured to form a Fourier transform of an object at an exit pupil of the Fourier lens assembly, disposing an aperture substantially at a Fourier transform plane configured to block a portion of incident light, providing a first zoom lens assembly including a second mounting portion, and removably mounting the second mounting portion to the first mounting portion.

[0008] Thus, various aspects of the present disclosure provide for the display of images having high dynamic range, high contrast ratio, and high resolution, leading to improvements in at least the fields of image projection, holography, signal processing, and the like. [Brief description of the drawings]

[0009] These and other more detailed and specific features of the various embodiments are more fully disclosed in the following description, taken in conjunction with the accompanying drawings.

[0010] [Figure 1] FIG. 1 is a block diagram of an exemplary projection system in accordance with various aspects of the present disclosure.

[0011] [Diagram 2] FIG. 2 illustrates an exemplary projection lens system according to various aspects of the present disclosure.

[0012] [Diagram 3] FIG. 3 illustrates an example lens configuration of a portion of the example projection lens system of FIG.

[0013] [Figure 4] FIG. 4 illustrates an example lens configuration for another portion of the example projection lens system of FIG.

[0014] [Diagram 5]FIG. 5 is a diagram illustrating an exemplary assembled lens configuration of the exemplary projection lens system of FIG.

[0015] [Figure 6A] FIG. 6A illustrates an exemplary method for providing a projection lens system according to various aspects of the present disclosure. [Figure 6B] FIG. 6B illustrates an exemplary method of providing a projection lens system according to various aspects of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present disclosure and aspects thereof may be embodied in a variety of forms: computer-implemented methods, computer program products, hardware, devices, or circuits controlled by computer systems and networks, user interfaces, and application programming interfaces, as well as hardware-implemented methods, signal processing circuits, memory arrays, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), etc. The foregoing summary is intended only to provide a general idea of ​​various aspects of the disclosure and is not intended to limit the scope of the disclosure in any way.

[0017] In the following description, numerous details are set forth, such as optical device configurations, timing, operation, etc., to provide an understanding of one or more aspects of the present disclosure. Those skilled in the art will readily appreciate that these specific details are merely exemplary and are not intended to limit the scope of the present application.

[0018] Additionally, while this disclosure primarily focuses on examples in which the various circuits are used in a digital projection system, it will be understood that this is merely one example implementation, and it will be further understood that the disclosed systems and methods can be used in any device where there is a need to project light, such as cinemas, consumer and other commercial projection systems, heads-up displays, virtual reality displays, etc.

[0019] <Projector system> In cinema applications, a projection system projects an image onto a theater screen for viewing by an audience seated in the theater. Different theaters have different physical parameters (e.g., room size, screen size, distance between the screen and the projector, lighting, etc.). Projection zoom systems are available with different focal lengths to suit different theaters. In some projection zoom lens systems, the Fourier plane (i.e., the plane where the Fourier transform of the object is formed) is built into the lens assembly and is therefore out of reach. In some cases, the Fourier plane is actually within the optical elements of the projection zoom lens system, and in different projection zoom lens systems, the Fourier plane may be at different focal lengths. As a result, the appropriate Fourier aperture varies for each focal length, and many different aperture sizes may be required for each lens system.

[0020] Projectors or other display systems including or associated with Fourier planes and apertures are described in commonly assigned patents and patent applications, such as WIPO Publication No. 2019 / 195182 entitled "Systems and Methods for Digital Laser Projection with Increased Contrast Using Fourier Filter", the entire contents of which are incorporated herein by reference. Comparative projection zoom lens systems that are not inherently modular do not allow access to the Fourier plane to exchange or swap out the Fourier aperture. Moreover, such comparative systems cannot be adapted to the full range of theater parameters without replacing the entire projection zoom lens system.

[0021] To allow access to the Fourier plane and provide the ability to fit a full range of theaters, a projection system including a modular projection zoom lens system may be provided. Figure 1 illustrates an exemplary high contrast projection system 100 according to various aspects of the present disclosure. In particular, Figure 1 illustrates the projection system 100 including a light source 101 configured to emit a first light 102, illumination optics 103 configured to receive and redirect or otherwise modify the first light 102, thereby generating a second light 104, a DMD 105 configured to receive and selectively redirect and / or modulate the second light 104 as a third light 106, a filter 107 configured to filter the third light 106, thereby generating a fourth light 108, and a projection optics 109 (an example of a projection lens system according to various aspects of the present disclosure) configured to receive the fourth light 108 and project it as a fifth light 110 onto a screen 111. The various elements of projection system 100 may be operated by or under the control of a controller 112. Controller 112 may be, for example, one or more processors, such as a central processing unit (CPU) of projection system 100.

[0022] In a 3D projection implementation, a physical projector may include two projection systems 100 positioned side-by-side, with each projection system 100 projecting an image corresponding to one eye of the viewer, or the physical projector may utilize one combined projection system 100 to project individual images corresponding to both eyes of the viewer.

[0023] The DMD 105 may include a number of reflective elements (micromirrors, or simply "mirrors") arranged, for example, in a two-dimensional array. In some examples, the resolution (i.e., the number of reflective elements) of the DMD 105 may be 2K (2048×1080), 4K (4096×2160), 1080p (1920×1080), consumer 4K (3840×2160), etc. Each reflective element receives a portion of the second light 104 from the illumination optics 103 and selectively transmits the light to the projection optics 109 via the filter 107. Thus, the reflective elements may be formed of or coated with any highly reflective material, such as aluminum or silver, to specularly reflect the light. Furthermore, to properly transmit the light, each reflective element may be configured to switch between an on position, in which the light is reflected toward the filter 107, and an off position, in which the light is reflected toward a light dump. Such switching may be performed under the control of the controller 112.

[0024] In practical implementations, projection system 100 may include fewer optical elements or may include additional optical elements such as mirrors, lenses, waveguides, optical fibers, beam splitters, diffusers, etc. With the exception of screen 111, the components illustrated in FIG. 1 may be integrated into a housing to provide a projection device. Such a projection device may include additional components such as memory, input / output ports, communication circuitry, power supplies, etc.

[0025] The light source 101 may be, for example, a laser light source, an LED, or the like. In general, the light source 101 is any light emitter that emits coherent light. In some embodiments of the present disclosure, the light source 101 may include multiple individual light emitters, each corresponding to a different wavelength or wavelength band. The light source 101 emits light in response to an image signal provided by the controller 112. The image signal includes image data corresponding to multiple frames to be displayed sequentially. Individual elements in the projection system 100, including but not limited to the DMD 105 and the projection optics 109, may be controlled by the controller 112. The image signal may be obtained from an external source, streaming or cloud-based, may be obtained from an internal memory of the projection system 100, such as a hard disk, may be obtained from a removable media operably connected to the projection system 100, or may be a combination thereof.

[0026] Although FIG. 1 illustrates a generally straight light path, in practice the light path is generally more complicated. For example, in projection system 100, second light 104 from illumination optics 103 is steered toward DMD chip 105 (or chips) at a fixed angle determined by the steering angle of the DMD mirror, and is directed through filter 107 to projection optics 109. Furthermore, while FIG. 1 illustrates filter 107 as being optically upstream from projection optics 109, in practice filter 107 may be located at a location within projection optics 109, as described in more detail below. Projection optics 109 includes one or more optical elements, such as lenses, as described in more detail below. In some embodiments, the Fourier stop of projection system 100 is located within an assembly housing projection optics 109.

[0027] <Modular projection lens system> To accommodate differences between theaters, systems and methods may be provided that allow ready access to the Fourier aperture when setting up the projection system 100. Because the position of the aperture (and its size) depends on the wavelength of the projection light, the illumination angle, and the tilt angle of the DMD 105 (all of which may vary from projector to projector), having access to the Fourier aperture may facilitate calibration and adjustment of the apparatus. In some embodiments, it may even be possible to measure the contrast and / or efficiency of the image while these adjustments are being made.

[0028] FIG. 2 is an exploded view of an exemplary projection lens system 200 according to various aspects of the disclosure. The projection lens system 200 is an example of the projection optical system 109 illustrated in FIG. 1. To allow access to the Fourier stop when setting up the projection system 100, the projection lens system 200 has a modular design. The projection lens system 200 includes a Fourier section 201 (also called a Fourier lens assembly), an aperture 202, and a zoom section 203 (also called a zoom lens assembly) configured to form a Fourier transform of an object at its exit pupil, as described in more detail below. As used herein, a "Fourier section" or "Fourier lens assembly" refers to an optical system that spatially Fourier transforms modulated light (e.g., light from the DMD 105) by focusing the modulated light on a Fourier plane. The spatial Fourier transform imposed by the Fourier section 201 converts the propagation angle of each diffraction order of the modulated light to a corresponding spatial position on the Fourier plane. This allows the Fourier unit 201 to select the desired diffraction orders and filter out the undesired diffraction orders by spatial filtering in the Fourier plane. Note that the spatial Fourier transform of the modulated light in the Fourier plane corresponds to the Fraunhofer diffraction pattern of the modulated light.

[0029] The Fourier section 201 includes a first mounting section 204, which may include threads, fasteners, or the like. The zoom section 203 includes a second mounting section 205, which may include complementary threads, fasteners, or the like to allow mating with the first mounting section 204. In one example, the first mounting section 204 includes a male threaded portion and the second mounting section 205 includes a female threaded portion, or vice versa. In another example, the first mounting section 204 and the second mounting section 205 are configured to frictionally fit. In this case, one or more fastening elements, such as screws, cams, flanges, or the like, may be provided. In yet another example, the first mounting section 204 may include one or more radial pins and the second mounting section 205 may include a corresponding number of L-shaped slots, or vice versa, thereby connecting the Fourier section 201 and the zoom section 203 using a bayonet connection. According to these examples, the Fourier section 201 can be removably attached to the zoom section 203 to provide a modular assembly, as described in more detail below.

[0030] Although the Fourier section 201 and the zoom section 203 are illustrated in FIG. 2 as being completely separable, the present disclosure is not limited thereto. In some embodiments, the Fourier section 201 and the zoom section 203 are only partially separable, for example, by providing an access portion in one of the Fourier section 201 and the zoom section 203. The access portion may be a slot, a door, a window, or the like, allowing an operator to access and / or replace the aperture 202 through the access portion. In these embodiments, the Fourier section 201 and the zoom section 203 may be joined together (e.g., via an adhesive on the first mounting section 204 and / or the second mounting section 205) so as not to be completely separable. Alternatively, the Fourier section 201 and the zoom section 203 may be provided with an integrated housing including the mounting portion.

[0031] The aperture 202 may be an example of the filter 107 illustrated in FIG. 1. The aperture 202 is configured to block a portion of the light in the projection lens system 200 (e.g., modulated light corresponding to one or more diffraction orders). As illustrated in FIG. 2, the aperture 202 is, for example, a square opening with sides of 6 mm length. FIG. 2 also illustrates an optical axis 210 of the projection lens system 200. When assembled, the Fourier section 201 and the zoom section 203 are substantially coaxial with each other and with the optical axis 210. In some aspects (e.g., depending on the illumination angle), the aperture 202 is also substantially coaxial with the optical axis 210.

[0032] The projection lens system 200 may include or be associated with one or more non-optical elements, including heat dissipation devices such as heat sinks (or cooling fins), one or more adhesives (or fasteners), etc. In some aspects, the aperture 202 blocks and results in absorption of approximately 15% of the incident light, so the heat sink or cooling fins may be positioned and configured to adequately dissipate heat from the aperture 202. In some aspects, the aperture 202 is thermally isolated from other portions of the projection lens system 200.

[0033] The Fourier section 201 and the aperture 202 collectively act as a Fourier lens with a spatial filter that can also be used as a fixed throw projection lens. The zoom section 203 illustrated in FIG. 2 can be one of a family of zoom lens assemblies configured to be attached to the Fourier section 201. This allows a family of projection zoom lens systems to be created and adapted to different theaters. In other words, the Fourier section 201 and the aperture 202 are applicable to any theater setting, while the zoom section 203 provides a specific projection light pattern tailored to a specific theater. Thus, by selecting a specific zoom section 203 from a family of zoom lens assemblies and attaching the selected zoom section 203 to the Fourier section 201 and the aperture 202, a projection lens system 200 adapted to the specific theater can be realized.

[0034] Both the Fourier section 201 and the zoom section 203 may include multiple individual lens elements. Exemplary configurations of lens elements in the Fourier section 201 and the zoom section 203 are illustrated in Figures 3 and 4, respectively.

[0035] FIG. 3 illustrates an exemplary optical system of an exemplary Fourier section 300 including a prism 301 (only a portion of which is shown in FIG. 3) and a Fourier lens system 302 having multiple lenses (also referred to as lens elements). A Fourier plane 303 of the Fourier lens system 302 is also illustrated with an exemplary light ray 310 to explain the optical behavior of the Fourier section 300. The Fourier lens system 302 may be housed within the housing of the Fourier section 201 illustrated in FIG. 2. In some examples, the prism 301 is also housed within the housing of the Fourier section 201, while in other examples, the prism 301 may be located optically upstream from the projection lens system 200 and optically downstream from the DMD 105. The Fourier plane 303 may correspond approximately (e.g., within 10 mm) to the position of the aperture 202.

[0036] The individual lens elements that make up the Fourier lens system 302 may be selected to produce a low distortion image at infinity, with the exit pupil located at the Fourier plane 303. Reducing the aberrations of the Fourier lens system 302 may increase the ease of design of the associated zoom portion(s). The particular Fourier lens system 302 illustrated in Figure 3 has distortion of less than 0.1%.

[0037] The Fourier lens system 302 is telecentric, exhibits low wavefront error to minimize any effect on the imaging of the Fourier plane 303, exhibits low chromatic aberration, introduces low distortion, and is located a distance d from the most proximal optical element. f (approximately coincident with the Fourier plane 303) to reduce the small area heat load on the most proximal optical element. As shown, the most proximal optical element is the downstream surface of the last lens in the Fourier lens system 302. The distance d fThe minimum magnitude of depends on the parameters of the Fourier lens system 302, including the material type of the lenses in the Fourier lens system 302 and / or the material type of the aperture 202 that will be approximately located at the Fourier plane 302. f Although a size of >12 mm may be sufficient to mitigate small area heat loads, in some embodiments, the distance d f is preferably approximately equal to 40 mm (eg, within 10% of 40 mm).

[0038] Fourier section 300 may include other optical elements in addition to prism 301 and Fourier lens system 302. In some examples, Fourier section 300 may include one or more electronic crystals (e.g., translucent liquid crystal elements that impart a deflection to light passing therethrough based on an applied voltage profile) or other deflecting elements, thereby shifting the projected image on screen 111.

[0039] Additionally, the Fourier lens system 302 can be used as a projection lens once refocused, thereby allowing adjustment of the Fourier aperture and / or contrast of the projected image without requiring disassembly of the entire projection lens system 200, facilitating calibration or defect detection, etc.

[0040] In addition to its use as part of the projection lens system 200, the Fourier section 300 may have further uses as a result of its separability from other elements of the projection lens system 200. Such further uses may include facilitating calibration or installation of the projection system 100. For example, the Fourier section 300 may be used as a stand-alone optical system for: testing the focusing and convergence of the DMD, including but not limited to the DMD 105; making an initial observation of potential image quality issues with elements of the projection system 100, including but not limited to the light source 101, the illumination optics 103, the DMD 105, and / or the prism 301; facilitating sizing and positioning of the Fourier stop 202; or measuring the on / off contrast of the projection system 100. Alternatively, a simplified fixed lens may be attached to the Fourier section 300 for purposes of calibration, testing, defect detection, sizing and positioning, measurement, etc.

[0041] 4 illustrates an example optical system of an example zoom section 400 in several zoom configurations. The zoom section 400 includes a fixed lens group 401, a first movable lens group 402, a second movable lens group 403, and a third movable lens group 404. 3 4 includes a movable lens group 404 of Fourier plane 405. A Fourier plane 405 is also shown with exemplary light rays 410 to explain the optical behavior of the zoom section 400. The lens group shown in FIG. 4 may be housed within the housing of the zoom section 203 shown in FIG. 2. When the zoom section 400 is assembled with the Fourier section 300, the Fourier plane 303 and the Fourier plane 405 may correspond to each other and may be positioned substantially at the position of the aperture 202.

[0042] Zoom section 400 may include other optical elements in addition to fixed lens group 401, first movable lens group 402, second movable lens group 403, and third movable lens group 404. In some examples, zoom section 400 includes an electronic crystal or other deflecting element, which can shift the projected image on screen 111.

[0043] The zoom section 400 works like a telescope. That is, the object of the zoom section 400 is assumed to be near infinity, and the image side of the zoom section 400 is configured to form a real image at a typical screen distance (e.g., 10-30 m). The zoom section 400 illustrated in FIG. 4 is configured to accommodate a range of zoom configurations depending on the specific positions of the first movable lens group 402, the second movable lens group 403, and the third movable lens group 404. By appropriately moving the first movable lens group 402, the second movable lens group 403, and the third movable lens group 404, it is possible to change the throw ratio of the zoom section 400 (i.e., the distance between the zoom section 400 and the screen 111 divided by the width of the screen 111). In the particular example illustrated in FIG. 4, the zoom section 400 is configured to provide a range of zoom configurations from a throw ratio of 2:1 (top configuration) to a throw ratio of 3:1 (bottom configuration) using an exemplary DMD. However, in a practical manner, the range of zoom configurations is not so limited. In some examples, the throw ratio may be greater than or equal to 1.2:1 and less than or equal to 4:1.

[0044] In some embodiments, the zoom section 400 has a fixed throw ratio rather than being configured to obtain a range of zoom configurations. In such embodiments, the first movable lens group 402, the second movable lens group 403, and the third movable lens group 404 of FIG. 4 may be replaced with corresponding fixed lens groups. For example, the first movable lens group 402, the second movable lens group 403, and the third movable lens group 404 of the top configuration of FIG. 4 may be replaced with second fixed lens group, third fixed lens group, and fourth fixed lens group, respectively, to provide the zoom section 400 with a fixed throw ratio of 2:1. Also, the fixed throw ratio may be greater than or equal to 1.2:1 and less than or equal to 4:1. The zoom section 400 may still be referred to as a "zoom" section, regardless of whether it includes movable lens groups to provide a range of throw ratios or only fixed lens groups to provide a fixed throw ratio.

[0045] Since the Fourier lens system 302 produces an image of the DMD (e.g., DMD 105) at infinity (when so positioned), the zoom section 400 operates as a zoom telescope. Furthermore, the particular design of the lenses and lens groups of the zoom section 400 may be independent of the particular design of the Fourier lens system 302. The complexity of the zoom lens assembly is related to the degree of aberration correction obtained. In some embodiments of the present disclosure, the performance of the complete projection lens system 200 complies with Digital Cinema Initiatives (DCI) imaging standards, such as the DCI Digital Cinema System Specification (DCSS) version 1.3 or newer.

[0046] The Fourier section 300 and the zoom section 400 can be combined to realize a complete lens system. FIG. 5 shows an exemplary assembled lens configuration from such a combination. In FIG. 5, elements having the same reference numbers as those described above are indicated using the same reference numbers, and detailed descriptions thereof will not be repeated here. FIG. 5 shows assembled lens configurations where the zoom section 400 is in a 2:1 throw ratio configuration (top, corresponding to the top of FIG. 4) and where the zoom section 400 is in a 3:1 throw ratio configuration (bottom, corresponding to the bottom of FIG. 4).

[0047] The Fourier section 300 and the zoom section 400 are assembled such that the Fourier plane 303 of the Fourier section 300 and the Fourier plane 405 of the zoom section 400 are coplanar. Because the two parts are joined in collimated or substantially collimated optical space, the tolerance requirements for mating the two parts are relaxed. Even if the optical axes of the Fourier section 300 and the zoom section 400 are misaligned (e.g., if one of the parts is misaligned in a direction perpendicular to the optical axis), such that the aperture spot is misaligned from the optical axis, there is likely to be no noticeable loss in image quality, despite the possibility of misalignment of the projected image on the screen 111. In some examples, the Fourier section 300 and the zoom section 400 are considered to be substantially coaxial if their optical axes are parallel and within 1 mm of each other.

[0048] Because the output of the Fourier section 300 and the input of the zoom section 400 are in collimated or substantially collimated optical space, the presence of dust on exposed lens surfaces in this region will not cause image artifact problems. If desired, flat windows can be placed at the output of the Fourier section 300 and the input of the zoom section 400 to protect the respective lens elements therein, and the flat windows can be cleaned without completely disassembling the entire system.

[0049] In some embodiments, the zoom unit 400 further comprises Equipped with internal focus function Some comparative Digital Light Processing (DLP) cinema lenses are Equipped with external focus function However, this means that any lens mount must be moved in two directions perpendicular to the optical axis (i.e., the x-axis and y-axis in a Cartesian coordinate system) as well as along the optical axis (i.e., the z-axis) to position the projected image. Equipped with internal focus function In an embodiment, there is no requirement for movement along the z-axis, and therefore the projection lens system 200 may be structurally more sound and less complex. Equipped with external focus function A comparative DLP cinema lens may require a motor in the lens mount to move the complete lens system. The air gap between the first and second doublet lenses of the third movable lens group 404 may perform the focus function with a threaded focus assembly. In some examples, this mechanism may be motor driven.

[0050] In some aspects, the zoom section 400 may be configured to compensate for errors and / or aberrations in the Fourier section 300, or vice versa. For example, if the amount of aberration introduced by one particular lens in the Fourier lens system 302 is known, then a particular lens in the fixed lens group 401 may be designed to compensate for the aberration.

[0051] <How to provide the projection system> The individual optical elements of the projection can be manufactured by any known method. After the optical elements are manufactured, they can be assembled at the production site or at the destination site. Figure 6A shows an exemplary method of making the projection lens system 200 at the production site, and Figure 6B shows an exemplary method of making the projection lens system 200 at the destination site.

[0052] In either method, the individual optical elements may be initially fabricated, for example, at a manufacturing facility. The optical elements may then be appropriately assembled into a Fourier section 300 and a zoom section 400. In some embodiments, a single standardized Fourier section 300 may be utilized, which, due to the modularity of the projection lens system 200, may be appropriately paired with one of a number (e.g., 10-12) of different zoom sections 400. Once assembled, each of the Fourier section 300 and the zoom section 400 will include a corresponding mounting section 204 and 205, as described above.

[0053] In the method of FIG. 6A, the projection lens system 200 may be provided to an end user as an assembly. For example, a manufacturer or supplier may first provide a Fourier section (such as Fourier section 201 or Fourier section 300) in step 601a, provide an aperture (such as aperture 202) in step 602a, and provide a zoom section (such as zoom section 203 or zoom section 400) in step 603a. At this point, the manufacturer or supplier may assemble the projection lens system 200, for example, by removably attaching the zoom section to the Fourier section with the aperture sandwiched therebetween. Assembling the projection lens system 200 may further include calibrating the projection lens system 200. The assembled projection lens system 200 may then be provided to an end user.

[0054] In the method of FIG. 6B, the projection lens system 200 may be provided to the end user in parts. For example, the manufacturer or supplier may first provide a Fourier section (such as Fourier section 201 or Fourier section 300) in step 601b and provide an aperture (such as aperture 202) in step 602b. Because the manufacturer or supplier may not know in advance which zoom section is most appropriate for a particular application (e.g., a particular theater) desired by the end user, the manufacturer or supplier may wait, solicit, and / or receive a request for a particular zoom section (such as zoom section 203 or zoom section 400) from the end user in step 603b. In some examples, the request may not be for a particular zoom section, but may instead include one or more parameters (e.g., the throw ratio of the zoom section, theater size, screen size, etc.). The manufacturer or supplier may then provide the appropriate zoom section to the end user in step 604b. The Fourier section and aperture may be provided to an end user assembled at 601b and 602b, for example, with a default zoom section having a default removable attachment, In such an example, providing the zoom section at 604b may include removing the default zoom section from the Fourier section and aperture and replacing the default zoom section with the zoom section provided at 604b.

[0055] In some examples, the manufacturer or supplier may further assemble the projection lens system 200, for example, by removably attaching a zoom portion to the Fourier portion with an aperture therebetween. As described above, assembling the projection lens system 200 may further include calibrating the projection lens system 200. The assembled projection lens system 200 may then be provided to an end user.

[0056] <Effects> The projection systems and methods may provide configurations with modular projection lens assemblies in which a first optical component and a second optical component are removably attached to one another, thereby allowing access to the Fourier plane and adaptability to a variety of theater settings.

[0057] The systems, methods, and apparatus according to the present disclosure may have one or more of the following configurations.

[0058] (1) A projection lens system comprising: a Fourier lens assembly having a first mounting portion and configured to form a Fourier transform of an object at an exit pupil of the Fourier lens assembly; an aperture configured to block a portion of incident light and located approximately at a Fourier transform plane; and a zoom lens assembly having a second mounting portion configured to be removably mounted to the first mounting portion.

[0059] (2) The projection lens system described in (1), wherein the first mounting portion and the second mounting portion are configured to engage with each other by at least one of a thread, a fastener, a screw, a cam, a flange, a pin, or a slot.

[0060] (3) The projection lens system according to (1) or (2), wherein, in an assembled state, the Fourier lens assembly and the zoom lens assembly are substantially coaxial.

[0061] (4) A projection lens system according to any one of (1) to (3), wherein the Fourier lens assembly includes a plurality of lenses.

[0062] (5) The projection lens system described in (4), wherein the distance between the plane and the nearest lens surface of the plurality of lenses is greater than 12 mm.

[0063] (6) A projection lens system described in any one of (1) to (5), wherein the Fourier lens assembly includes an electronic crystal configured to shift the projected image in a direction perpendicular to the optical axis of the Fourier lens assembly.

[0064] (7) A projection lens system according to any one of (1) to (6), wherein the Fourier lens assembly is telecentric.

[0065] (8) The projection lens system of any one of (1) to (7), wherein the Fourier lens assembly is configured to compensate for aberrations introduced by the zoom lens assembly.

[0066] (9) A projection lens system according to any one of (1) to (8), wherein the zoom lens assembly is configured to compensate for aberrations introduced by the Fourier lens assembly.

[0067] (10) A projection lens system according to any one of (1) to (9), further comprising a heat dissipation device configured to dissipate heat from the aperture.

[0068] (11) A projection lens system according to any one of (1) to (10), wherein the aperture is thermally isolated from the Fourier lens assembly and the zoom lens assembly.

[0069] (12) The zoom lens assembly Equipped with internal focus function 2. A projection lens system according to any one of (1) to (11).

[0070] (13) The projection lens system according to any one of (1) to (12), wherein the zoom lens assembly includes a fixed lens group and at least one movable lens group.

[0071] (14) A projection lens system according to any one of (1) to (13), wherein the zoom lens assembly includes a plurality of fixed lens groups.

[0072] (15) A projection lens system according to any one of (1) to (14), wherein the Fourier lens assembly has a first flat window at an output of the Fourier lens assembly and the zoom lens assembly has a second flat window at an input of the zoom lens assembly.

[0073] (16) A method of providing a projection lens system, comprising: providing a Fourier lens assembly having a first mounting portion and configured to form a Fourier transform of an object at an exit pupil of the Fourier lens assembly; disposing an aperture configured to block a portion of incident light at approximately the Fourier transform plane; providing a first zoom lens assembly including a second mounting portion; and removably mounting the second mounting portion to the first mounting portion.

[0074] (17) The method of (16), further comprising: providing a second zoom lens assembly having a third mounting portion; detaching the second mounting portion from the first mounting portion; and removably attaching the third mounting portion to the first mounting portion.

[0075] (18) The method of (16) or (17), wherein the first mounting portion and the second mounting portion are configured to mate by at least one of a thread, a fastener, a screw, a cam, a flange, a pin, or a slot.

[0076] (19) A method according to any one of (16) to (18), wherein the second mounting portion and the first mounting portion are removably mounted so that the Fourier lens assembly and the first zoom lens assembly are substantially coaxial.

[0077] (20) The method of any one of (16) to (19), further comprising: receiving a zoom lens assembly request; and providing the first zoom lens assembly in response to the zoom lens assembly request.

[0078] With respect to the processes, systems, methods, heuristics, etc. described herein, the steps of the processes, etc. are described as occurring according to a certain ordered sequence, but it should be understood that the steps can be performed in an order other than that described herein to implement the processes. Furthermore, it should be understood that certain steps can be performed simultaneously, other steps can be added, or certain steps described herein can be omitted. In other words, the process descriptions herein are provided for the purpose of illustrating particular embodiments, and should not be construed as limiting the scope of the claims in any way.

[0079] Therefore, it is understood that the above description is illustrative rather than limiting. Many embodiments and applications other than the examples described will become apparent upon reading the above description. The scope should be determined not with reference to the above description, but with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that the technology discussed herein will develop in the future, and that the systems and methods disclosed herein will be incorporated into such future embodiments. In short, it should be understood that the present application is capable of modification and variation.

[0080] All terms used in the claims are intended to be given their broadest reasonable interpretation and ordinary meaning as understood by those skilled in the art described herein, unless expressly stated to the contrary in the specification. In particular, the use of singular articles such as "a," "the," "said," etc., should be read as describing one or more of the indicated elements, unless an express limitation to the contrary is recited in the claim.

[0081] The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Moreover, in the foregoing Detailed Description, it will be seen that various features have been grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the claimed embodiments comprise more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Accordingly, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as separately claimed subject matter.

Claims

1. a Fourier lens assembly having a first mounting portion, the Fourier lens assembly configured to form a Fourier transform of an object in a Fourier plane at an exit pupil of the Fourier lens assembly; a stop configured to block a portion of the incident light and located approximately at the Fourier plane; a zoom lens assembly having a second mounting portion configured to be removably mounted to the first mounting portion to provide access to the aperture; A projection lens system comprising:

2. The projection lens system of claim 1 , wherein the Fourier plane is adjacent to the first mounting portion.

3. 10. The projection lens system of claim 1, wherein the first mounting portion and the second mounting portion are configured to mate by at least one of a thread, a fastener, a screw, a cam, a flange, a pin, or a slot.

4. 2. The projection lens system of claim 1, wherein, in an assembled state, the Fourier lens assembly and the zoom lens assembly are substantially coaxial.

5. The projection lens system of claim 1 , wherein the Fourier lens assembly comprises a plurality of lenses.

6. 6. The projection lens system of claim 5, wherein a distance between the Fourier plane and a most proximal lens surface of the plurality of lenses is greater than 12 mm.

7. 2. The projection lens system of claim 1, wherein the Fourier lens assembly includes an electronic crystal configured to shift the projected image in a direction perpendicular to an optical axis of the Fourier lens assembly.

8. 2. The projection lens system of claim 1, wherein the Fourier lens assembly is telecentric.

9. 2. The projection lens system of claim 1, wherein the Fourier lens assembly is configured to compensate for aberrations introduced by the zoom lens assembly.

10. 2. The projection lens system of claim 1, wherein the zoom lens assembly is configured to compensate for aberrations introduced by the Fourier lens assembly.

11. 10. The projection lens system of claim 1, further comprising a heat dissipation device configured to dissipate heat from the aperture.

12. 2. The projection lens system of claim 1, wherein the aperture is thermally isolated from the Fourier lens assembly and the zoom lens assembly.

13. 2. The projection lens system of claim 1, wherein the zoom lens assembly has an internal focus function.

14. The projection lens system of claim 1 , wherein the zoom lens assembly includes a fixed lens group and at least one movable lens group.

15. The projection lens system of claim 1 , wherein the zoom lens assembly includes a plurality of fixed lens groups.

16. 2. The projection lens system of claim 1, wherein the Fourier lens assembly has a first flat window at an output of the Fourier lens assembly and the zoom lens assembly has a second flat window at an input of the zoom lens assembly.

17. providing a Fourier lens assembly having a first mounting portion, the Fourier lens assembly configured to form a Fourier transform of an object in a Fourier plane at an exit pupil of the Fourier lens assembly; disposing an aperture configured to block a portion of the incident light approximately at the Fourier plane; providing a first zoom lens assembly including a second mount configured to be removably mounted to the first mount to provide access to the aperture; removably attaching the second mounting portion to the first mounting portion; A method for providing a projection lens system comprising:

18. providing a second zoom lens assembly having a third mount; Detaching the second mounting portion from the first mounting portion; removably attaching the third mounting portion to the first mounting portion; 20. The method of claim 17, further comprising:

19. 20. The method of claim 17, wherein the first mounting portion and the second mounting portion are configured to mate by at least one of a thread, a fastener, a screw, a cam, a flange, a pin, or a slot.

20. 20. The method of claim 17, wherein the second mount and the first mount are removably mounted such that the Fourier lens assembly and the first zoom lens assembly are substantially coaxial.

21. receiving a zoom lens assembly request; In response to the zoom lens assembly request, the first zoom lens assembly is used. To be aware of this and 20. The method of claim 17, further comprising:

Images