Projection System

Abstract

Exemplary embodiments provide systems and methods for correcting non-uniformity in a light beam generated by a multi-emitter light source. In some embodiments, a phase modulator displays a patch lens to correct the non-uniformity. In some embodiments, each region of the phase modulator is illuminated by a beam generated by one emitter of the multi-emitter light source. Such a region of the phase modulator may display a patch lens to correct non-uniformity in the corresponding beam illuminating that region.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Application No. 63 / 150005, entitled PATCH CORRECTION FOR LIGHT GUIDING PROJECTOR, filed on February 16, 2021, which is hereby incorporated by reference for all purposes. For purposes of the United States, this application claims the benefit under 35 U.S.C. § 119 of U.S. Application No. 63 / 150005, entitled PATCH CORRECTION FOR LIGHT GUIDING PROJECTOR, filed on February 16, 2021.

[0002] The present invention relates to correcting non-uniformities in light beams. One exemplary application of the invention is in the field of light projection, for example illuminating a projector imager. [Background technology]

[0003] A projector system modulates a light beam to produce a desired image. A non-uniform light beam can cause unwanted artifacts, such as blurring, streaks, speckles, etc., to be present in the final image produced by the projector system.

[0004] Projector systems may require a large amount of light to provide a suitable bright image, for example on a large projection screen. Some projectors include a single very bright light source along with beam conditioning optics that collect the light from the source and deliver a uniform light beam to the imager. Such light sources may be undesirably expensive. Solid-state light sources such as solid-state lasers and high-brightness light-emitting diodes are currently available. However, in many applications, multiple solid-state light sources are required to provide sufficient light. This creates a problem of how to cost-effectively combine light from different light sources to illuminate the imager in a suitable manner.

[0005] Various manufacturers produce relatively inexpensive modules that combine several solid-state light sources into a single unit. However, in many cases, the light beams emitted from different light sources are different and / or not precisely aligned. For example, the light sources may not be spaced evenly apart, the light beams from different light sources may be emitted in different directions, the light beams emitted from different light sources may diverge differently, the light beams from different light sources may have various degrees of non-uniformity, etc. This makes such modules unsuitable for use in some projector systems.

[0006] There is a general desire for improved projector systems. Summary of the Invention

[0007] The present invention has many aspects. These include: · Methods and apparatus for projecting light; Cinema projectors; ·Consumer projectors; · Systems and methods for correcting non-uniformity in a light beam generated by a multi-emitter light source; · Systems and methods for aligning optical elements of a projector system; · Systems and methods for combining light of different wavelengths into an image; Systems and methods for homogenizing light, Includes.

[0008] One aspect of the invention provides a projection system. The projection system may include one or more light sources operable to emit a plurality of light beams. The projection system may also include a phase modulator having a two-dimensional array of pixels. The pixels may be controllable to retard the phase of light incident on the pixels by a variable amount. The phase modulator may have an active area in an optical path of the plurality of light beams. Each of the plurality of light beams may be incident on the active area of ​​the phase modulator in a corresponding one of a plurality of distinct regions of the active area of ​​the phase modulator. The projection system may also include a controller configured to set each pixel of the distinct regions of the phase modulator to represent an optical shape of a patch lens corresponding to the distinct region, the patch lens configured to correct for non-uniformity present in the corresponding one of the plurality of light beams.

[0009] In some embodiments, the distinct regions are arranged in an array comprising a number of rows and a number of columns.

[0010] In some embodiments, the light source comprises a multi-emitter light source including at least two rows and two columns of light emitting elements.

[0011] In some embodiments, the controller is configured to configure each pixel of a distinct region of the phase modulator to display a light-induced phase pattern in combination with the optical geometry of a corresponding patch lens.

[0012] In some embodiments, the optical shapes of the patch lenses corresponding to the distinct regions are based, at least in part, on the measured deviation of the corresponding light beam from ideal.

[0013] In some embodiments, the optical shape of the patch lens corresponding to the distinct regions is based, at least in part, on a measured deviation from ideal of the light field produced at the image plane after the corresponding light beam interacts with the phase modulator.

[0014] In some embodiments, the non-uniformity corrected includes at least one of pointing parallelism, collimation, and intensity distribution.

[0015] In some embodiments, the represented optical shape corresponds to the optical shape of a spherical lens.

[0016] In some embodiments, adjacent patch lenses abut one another.

[0017] In some embodiments, the entire active area of ​​the pixels of the two-dimensional array of phase modulators is covered by a number of patch lenses.

[0018] In some embodiments, the optical shape of each patch lens is generated independently.

[0019] In some embodiments, the optical shape of each patch lens is generated by a controller configured to perform an optimization process.

[0020] In some embodiments, the optimization process comprises iteratively varying the phase displacement of a pixel of a corresponding patch lens until one or more observed characteristics of the corresponding output beam indicate that the patch lens is adequately correcting the deviation of the light beam from ideal.

[0021] In some embodiments, the optimization process is performed sequentially for different ones of the patch lenses.

[0022] In some embodiments, the optimization process is performed in parallel for different ones of the patch lenses.

[0023] In some embodiments, the optimization process comprises performing a simulated annealing method to find the phase displacements of pixels in a region that will construct the phase pattern of the corresponding patch lens.

[0024] In some embodiments, each optical shape of the patch lenses specifies at least one of a focal length, an optical center shift, a parameterized astigmatism, and a tilt of the corresponding patch lens.

[0025] In some embodiments, at least one of the distinct regions is divided into a plurality of sub-regions, and the controller is configured to configure pixels of each of the plurality of sub-regions to display an optical shape corresponding to the sub-region.

[0026] In some embodiments, different portions of a single light beam illuminate two or more sub-regions of corresponding separate regions of the phase modulator.

[0027] In some embodiments, at least one of the plurality of optical shapes corresponds to a plurality of lenses superimposed on one another.

[0028] In some embodiments, at least one of the multiple light beams extends beyond multiple distinct regions.

[0029] In some embodiments, one or more of the plurality of optical shapes are each changed in real time to take into account changing characteristics of a corresponding one of the plurality of light beams.

[0030] In some embodiments, the optical geometry applied to each of the multiple light beams further comprises a light directing component that directs the light.

[0031] In some embodiments, the corresponding patch lens and the corresponding light directing component are overlapped.

[0032] In some embodiments, the light directing components applied to different ones of the light beams are the same.

[0033] In some embodiments, the light directing components applied to the different light beams are different.

[0034] In some embodiments, the light directing component is configured to direct the light beam to converge at a number of different points.

[0035] In some embodiments, the controller individually controls each of the separate regions of the phase modulator to display a pattern of phase shift that directs light from a corresponding light beam.

[0036] In some embodiments, the optical shape of each of the multiple patch lenses and the corresponding light directing component are calculated independently of one another.

[0037] In some embodiments, the optical shape of each of the multiple patch lenses and the corresponding light directing component are calculated together.

[0038] In some embodiments, the projector comprises receive optics upstream of the phase modulator, which are configured to shape or modify the light beam to better illuminate the phase modulator.

[0039] In some embodiments, the receiving optics shapes the light from the light beam so that it matches the size of a pixel in the two-dimensional array.

[0040] In some embodiments, the controller is configured to configure at least a portion of the plurality of pixels of the phase modulator to display a selected phase pattern to cause specular reflection of at least a portion of the plurality of light beams.

[0041] In some embodiments, the controller is configured to dynamically vary the number of pixels in the portion of the plurality of pixels to adjust the ratio of unguided light to guided light.

[0042] In some embodiments, the controller is configured to determine a desired ratio of undirected light to directed light based at least in part on processing the image data.

[0043] In some embodiments, the controller is configured to determine a desired ratio of unguided light to guided light based at least in part on one or more of: a black level of the image data, a maximum brightness of highlights in the image data, and a contrast of the image data.

[0044] In some embodiments, the projector further comprises a coupling rod downstream of the phase modulator. The coupling rod may have entrance and exit apertures and light reflective portions on either side of a central longitudinal axis of the coupling rod. The coupling rod may be configured to combine the guided and unguided light and homogenize the unguided light by repeated reflections at the reflective portions before reaching the exit aperture.

[0045] In some embodiments, the coupling rod is a passive optical device.

[0046] In some embodiments, the connecting rod comprises a hollow tube.

[0047] In some embodiments, the coupling rod comprises a solid body of permeable material.

[0048] In some embodiments, the transparent material is at least one of glass, quartz, and transparent plastic.

[0049] In some embodiments, the solid comprises a light-reflecting or light-scattering layer or coating.

[0050] In some embodiments, the connecting rod comprises a hollow rectangular tube that includes at least one tapered surface.

[0051] In some embodiments, the coupling rod has two flat reflective surfaces that taper from an entrance opening to an exit opening, which may be larger than the exit opening.

[0052] In some embodiments, the connecting rod is tapered in one plane.

[0053] In some embodiments, the coupling rod is tapered along the transverse axis of the coupling rod.

[0054] In some embodiments, the coupling rod is tapered along the vertical axis of the coupling rod.

[0055] In some embodiments, the connecting rod comprises a torsion rod.

[0056] In some embodiments, the torsional rod has at least one twist of about 90 degrees.

[0057] In some embodiments, the connecting rod has a body that includes a concave shape.

[0058] In some embodiments, the exit angle of the light from the exit aperture is about 45° or less.

[0059] In some embodiments, the coupling rods are configured to provide a substantially symmetric output.

[0060] In some embodiments, the projector further comprises a prism optically coupled to the coupling rod proximate the entrance opening, the prism may be configured to collect the unguided light and transmit the unguided light into the coupling rod.

[0061] In some embodiments, the projector further comprises an optical element that transmits the guided and unguided light from the phase modulator to the coupling rod.

[0062] In some embodiments, the optical element includes a physical lens located between the phase modulator and the coupling rod.

[0063] In some embodiments, the physical lens is positioned in a position that maximizes the incidence of guided and unguided light on the physical lens.

[0064] In some embodiments, the projector further comprises a diffuser in the optical path of the guided light upstream of the coupling rod to diffuse the guided light.

[0065] In some embodiments, the projector further comprises a diffuser in the optical path of the unguided light upstream of the coupling rod.

[0066] In some embodiments, the projector further comprises a diffuser downstream of the coupling rod.

[0067] In some embodiments, the projector further comprises an optical system configured to generate base illumination to increase the intensity of the guided or unguided light.

[0068] In some embodiments, the optical system configured to generate the base illumination includes a mirror positioned adjacent to the phase modulator.

[0069] In some embodiments, the mirror is located in the plane of a pixel of a two-dimensional array of phase modulators.

[0070] In some embodiments, the mirror is parallel to the phase modulator.

[0071] In some embodiments, the mirror abuts one or more edges of the phase modulator.

[0072] In some embodiments, the mirror partially covers a pixel of a two-dimensional array of phase modulators.

[0073] In some embodiments, the optical system configured to generate the base illumination includes a prism configured to extract some light from the multiple light beams for use as the base illumination.

[0074] In some embodiments, the projector further comprises one or more additional light sources configured to generate base illumination to augment the intensity of the guided or unguided light.

[0075] In some embodiments, the projector includes a camera configured to capture images of the light-guided imagery and connected to provide the captured images to the controller.

[0076] In some embodiments, the controller is configured to process captured images of the light-induced imagery to determine characteristics of the light used to generate the light-induced imagery and to vary the optical shape of one or more of the plurality of patch lenses displayed by the phase modulator.

[0077] In some embodiments, the one or more light sources have emitters that emit polychromatic light.

[0078] In some embodiments, the optical shape of each of the plurality of patch lenses is configured based at least in part on the wavelength of the corresponding light beam.

[0079] In some embodiments, the one or more light sources have emitters that emit polychromatic light. The coupling rod may homogenize the different wavelengths of unguided light in one or both of the direction and color of the light.

[0080] In some embodiments, the optical shape of each of the plurality of patch lenses is configured based at least in part on the wavelength of the corresponding light beam.

[0081] In some embodiments, the projector further comprises one or more additional light sources of different wavelengths positioned to emit light into the coupling rod to increase the intensity of the unguided light.

[0082] Another aspect of the invention provides a projection system. The projection system may include a light source operable to emit at least one light beam. The projection system may also include a phase modulator having a two-dimensional array of pixels. The pixels may be controllable to retard the phase of light incident on the pixels by a variable amount. The phase modulator may have an active area in an optical path of the at least one light beam. The projection system may also include a controller configured to control the pixels of the phase modulator to apply a pattern of phase shifts to the light of the at least one light beam. The phase shifts may be selected to direct light that produces a highlight image. The projection system may also include an optical element arranged to transmit unguided light specularly reflected by the phase modulator to an entrance and exit aperture and a coupling rod having light reflecting portions on either side of a central longitudinal axis and direct the unguided light into an entrance aperture of the coupling rod such that the unguided light is homogenized by repeated reflections at the light reflecting portions before reaching the exit aperture. The projection system may also include an optical element arranged to transmit the guided light along a path to the coupling rod such that the guided light passes from the entrance opening of the coupling rod to the exit opening of the coupling rod without becoming homogenized and is mixed with the homogenized unguided light at the exit opening.

[0083] In some embodiments, the coupling rod is a passive optical device.

[0084] In some embodiments, the connecting rods are rectangular in cross section.

[0085] In some embodiments, the coupling rod comprises a hollow tube, and the guided light passes through a hole in the hollow tubular member.

[0086] In some embodiments, the coupling rod comprises a solid body of permeable material.

[0087] In some embodiments, the transparent material is at least one of glass, quartz, and transparent plastic.

[0088] In some embodiments, the solid comprises a light-reflecting or light-scattering layer or coating.

[0089] In some embodiments, the coupling rod is tapered such that the entrance opening has a larger area than the exit opening.

[0090] In some embodiments, the connecting rod comprises a hollow rectangular tube that includes at least one tapered surface.

[0091] In some embodiments, the coupling rod has two flat reflective surfaces that taper from an entrance opening to an exit opening, which may be larger than the exit opening.

[0092] In some embodiments, the connecting rod is tapered in one plane.

[0093] In some embodiments, the coupling rod is tapered along the transverse axis of the coupling rod.

[0094] In some embodiments, the coupling rod is tapered along the vertical axis of the coupling rod.

[0095] In some embodiments, the connecting rod comprises a torsion rod.

[0096] In some embodiments, the torsional rod has at least one twist of about 90 degrees.

[0097] In some embodiments, the connecting rod has a body that includes a concave shape.

[0098] In some embodiments, the exit angle of the light from the exit aperture is about 45° or less.

[0099] In some embodiments, the coupling rods are configured to provide a substantially symmetric output.

[0100] In some embodiments, the projector further comprises a prism optically coupled to the coupling rod proximate the entrance opening, the prism may be configured to collect the unguided light and transmit the unguided light into the coupling rod.

[0101] In some embodiments, the projector further comprises an optical element that transmits the guided and unguided light from the phase modulator to the coupling rod.

[0102] In some embodiments, the optical element includes a physical lens located between the phase modulator and the coupling rod.

[0103] In some embodiments, the physical lens is positioned in a position that maximizes the incidence of guided and unguided light on the physical lens.

[0104] In some embodiments, the projector further comprises a diffuser in the optical path of the guided light upstream of the coupling rod to diffuse the guided light.

[0105] In some embodiments, the projector further comprises a diffuser in the optical path of the unguided light upstream of the coupling rod to diffuse the unguided light.

[0106] In some embodiments, the projector further comprises a diffuser downstream of the combining rod to diffuse the combined guided and unguided light.

[0107] In some embodiments, the projector further comprises an optical system configured to generate base illumination to increase the intensity of the guided or unguided light.

[0108] In some embodiments, the optical system configured to generate the base illumination includes a mirror positioned adjacent to the phase modulator.

[0109] In some embodiments, the mirror is located in the plane of a pixel of a two-dimensional array of phase modulators.

[0110] In some embodiments, the mirror is parallel to the phase modulator.

[0111] In some embodiments, the mirror abuts one or more edges of the phase modulator.

[0112] In some embodiments, the mirror partially covers a pixel of a two-dimensional array of phase modulators.

[0113] In some embodiments, the optical system configured to generate the base illumination includes a prism configured to extract some light from the multiple light beams for use as the base illumination.

[0114] In some embodiments, the projection systems described herein further comprise one or more additional light sources configured to generate base illumination to augment the intensity of the guided or unguided light.

[0115] Another aspect of the invention provides a coupling rod for combining unguided light specularly reflected by a phase modulator with guided light phase shifted by the phase modulator. The coupling rod may have entrance and exit apertures. The coupling rod may also have light reflecting portions on either side of the longitudinal central axis of the coupling rod. Unguided light incident on the reflecting portions may be homogenized by being repeatedly reflected off the reflecting portions before reaching the exit aperture.

[0116] In some embodiments, the linking rod has any of the features described elsewhere herein.

[0117] Another aspect provides a method for aligning a plurality of elements of a projector system. The method may include capturing an image of a generated light pattern. The method may also include identifying a characteristic feature of the light pattern in the captured image. The method may also include comparing the identified characteristic feature to one or more reference features. The method may also include varying one or more optical shapes of a displayed plurality of patch lenses based on a comparison of the identified characteristic feature to the one or more reference features.

[0118] In some embodiments, the distinctive characteristics include at least one of the position, shape, intensity and uniformity of the individual portions of the light pattern.

[0119] In some embodiments, varying one or more optical shapes of the displayed plurality of patch lenses includes varying at least one of the following: The focal length of the corresponding patch lens; the location of the optical center of the corresponding patch lens; Lens tilt of the corresponding patch lens; The size of the corresponding patch lens; and The location of the lens area of ​​the corresponding patch lens within the distinct region of the phase modulator.

[0120] In some embodiments, varying one or more optical shapes of the displayed patch lenses includes: moving the center of the corresponding patch lens to find a best center position; and adjusting one or both of the lens focal length and size of the corresponding patch lens.

[0121] In some embodiments, varying the optical shape of one or more of the displayed patch lenses further comprises adjusting a tilt of a corresponding patch lens.

[0122] In some embodiments, the optical shapes are varied sequentially.

[0123] In some embodiments, multiple optical shapes are changed simultaneously.

[0124] In some embodiments, the method comprises distinguishing between portions of the light pattern resulting from different light beams by at least one of the following: Turn on the light beams one at a time; Turn off the light beams one at a time; varying the intensity of one or more of the plurality of light beams in a known manner; Varying different beam characteristics of different ones of the plurality of light beams; applying different light directing components to different ones of the plurality of light beams; and The optical shape of each patch lens is changed to change the beam pattern at different rates and / or in different directions.

[0125] Another aspect provides a method for powering up a projector system having any of the features described herein. The method may include retrieving from a data store a plurality of optical shapes corresponding to a plurality of patch lenses to be displayed by a phase modulator. The method may also include controlling the phase modulator to display the retrieved optical shapes to correct for non-uniformity in a light beam incident on the phase modulator.

[0126] In some embodiments, the method for powering on the projection system may also include capturing an image of the light pattern generated by the projector system. The method may also include varying one or more of the retrieved optical shapes based on a comparison of the identified features in the captured image and a reference feature.

[0127] Another aspect provides a method for projecting an image. The method may include emitting at least one light beam from a light source. The method may also include illuminating an active area of ​​a phase modulator having a two-dimensional array of pixels with the at least one light beam. The pixels may be controllable to retard the phase of light incident on the pixels by a variable amount. The method may also include controlling the pixels of the phase modulator to apply a pattern of phase shifts to light of the at least one light beam. The phase shifts may be selected to guide the light to generate a highlight image. The method may also include transmitting unguided light (which may be light specularly reflected by the phase modulator and / or other unguided light) to a coupling rod having entrance and exit openings and light reflecting portions on either side of a central longitudinal axis, and directing the unguided light into the entrance opening of the coupling rod such that the unguided light is homogenized by repeated reflections at the light reflecting portions before reaching the exit opening. The method may also include transmitting the guided light along a path to the coupling rod such that the guided light passes from the entrance opening of the coupling rod to the exit opening of the coupling rod without becoming homogenized and is mixed with the homogenized unguided light at the exit opening.

[0128] Further aspects and example embodiments are illustrated in the accompanying drawings and / or described in the following description.

[0129] It is emphasized that the invention relates to all combinations of the above features, even if these features are recited in different claims. [Brief description of the drawings]

[0130] The accompanying drawings illustrate non-limiting exemplary embodiments of the present invention.

[0131] [Figure 1] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0132] [Figure 1A] 2 is a schematic diagram of an exemplary illumination of a phase modulator of the optical arrangement of FIG. 1.

[0133] [Figure 2A] 1 is a schematic diagram of an exemplary illumination of a phase modulator.

[0134] [Figure 2B] FIG. 2B is a schematic diagram of the phase modulator of FIG. 2A.

[0135] [Figure 2C] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0136] [Figure 2D] FIG. 13 is a schematic diagram illustrating how a patch lens can have different lens properties in different sub-regions of a region of a phase modulator. [Figure 2E] FIG. 13 is a schematic diagram illustrating how a patch lens can have different lens properties in different sub-regions of a region of a phase modulator.

[0137] [Figure 2F] 1 is a schematic diagram showing how a light beam can interact with two or more patch lenses.

[0138] [Diagram 3] FIG. 2 is a schematic block diagram of an optical arrangement according to an exemplary embodiment of the present invention.

[0139] [Figure 4]1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0140] [Diagram 5] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0141] [Figure 6] 2 is a schematic block diagram of homogenization and / or recombination optics in accordance with an exemplary embodiment of the present invention;

[0142] [Figure 7] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0143] [Figure 7A] FIG. 2 is a schematic diagram of a connecting rod according to an exemplary embodiment of the present invention.

[0144] [Figure 7B] FIG. 2 is a schematic diagram of a connecting rod according to an exemplary embodiment of the present invention.

[0145] [Figure 7C] FIG. 2 is a schematic diagram of a connecting rod according to an exemplary embodiment of the present invention.

[0146] [Figure 8] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0147] [Figure 8A] 9 is a schematic diagram of the mirror of FIG. 8 in an optical arrangement according to an exemplary embodiment of the present invention.

[0148] [Figure 9] FIG. 2 is a schematic block diagram of an optical arrangement according to an exemplary embodiment of the present invention.

[0149] [Figure 10] FIG. 2 is a schematic block diagram of an optical arrangement according to an exemplary embodiment of the present invention.

[0150] [Figure 11] 1 is a schematic block diagram of an optical element alignment system in accordance with an exemplary embodiment of the present invention;

[0151] [Figure 12] 1 is a block diagram illustrating a method according to an exemplary embodiment of the present invention.

[0152] [Figure 13] 1 is a block diagram illustrating a method according to an exemplary embodiment of the present invention.

[0153] [Figure 14] 1 is a schematic diagram of an optical arrangement according to an exemplary embodiment of the present invention;

[0154] [Figure 15] FIG. 1 is a block diagram illustrating an example control system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0155] Throughout the following description, specific details are set forth to provide a more complete understanding of the invention. However, the invention can be practiced without being limited to these specific details. In other instances, well-known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. [Definition]

[0156] As used herein, "guided light" refers to a portion of light incident on a spatial phase modulator (or phase modulator) whose phase is controllably modulated by the phase modulator to cause the portion of light to be directed to a location on the image plane determined by a phase pattern applied to the phase modulator. By varying the phase pattern, the portion of light may be directed to illuminate different locations on the image plane. The guided light is directed by interference of light phase-shifted by different controllable elements (pixels) of the phase modulator.

[0157] As used herein, "unguided light" means the portion of the light incident on the spatial phase modulator that is not guided light. Unguided light may include the portion of the light incident on the spatial phase modulator that is specularly reflected by the spatial phase modulator.

[0158] As used herein, "desired light field" refers to a light field that has a desired shape, propagation direction and / or angle for efficient coupling with a typical optical system (e.g., imaging optics).

[0159] As used herein, "output optics" refers to image-forming optics, which may include a spatial amplitude modulator and / or associated projection optics that form the final image on a screen, or a relay system that provides an intermediate image.

[0160] As used herein, "light guided image" means an image produced by output optics when guided light is provided to the output optics. Examples of light guided images include a final on-screen image and an intermediate image.

[0161] As used herein, "highlight image" means an image formed by guided light or a portion of the light that comprises a light guided image.

[0162] As used herein, a "patch lens" refers to a phase pattern applied by a particular region of a phase modulator that functions as a lens. In some embodiments, a particular patch lens is illuminated by a single light beam. The patch lens may be configured to make the single light beam provide a desired light field. A set of patch lenses corresponding to a set of multiple separate light beams may be configured to compensate for differences between the multiple separate light beams.

[0163] The "optical geometry" of a patch lens refers to the particular phase shift applied to a pixel in an area of ​​a spatial phase modulator that corresponds to the patch lens. The optical geometry may be characterized by properties such as the focal length, optical center shift, astigmatism, tilt, size, etc. of the patch lens.

[0164] FIG. 1 illustrates an exemplary optical arrangement 10. The optical arrangement 10 may be designed to generate a desired light beam that illuminates a projector imager or other downstream optical system. The optical arrangement 10 includes a multi-emitter light source 12 that illuminates a spatial phase modulator 14. The multi-emitter light source 12 has a number of individual light-emitting elements 12-1, 12-2, 12-3, ..., 12-N-1, 12-N. Each of the individual light-emitting elements generates a corresponding light beam 13-1, 13-2, 13-3, ..., 13-N-1, 13-N, respectively (collectively, beam 13). The multi-emitter light source 12 may be positioned relative to the phase modulator 14 to maximize incidence of the beam 13 on the phase modulator 14.

[0165] In some embodiments, the multi-emitter light source 12 has at least two rows and two columns of light emitting elements. In some embodiments, the multi-emitter light source 12 has multiple light emitting diode (LED) emitters, multiple laser diodes, or the like.

[0166] It may be desirable to combine light from multiple light emitting elements 12-1, ..., 12-N of one or more multi-emitter light sources 12. This arrangement can provide a large amount of light that may be useful, for example, in producing bright images on large movie screens and / or in producing very high light intensity images for industrial processes.

[0167] The multi-emitter light source 12 may output non-uniform beams 13. For example, the individual beams 13 may have different pointing parallelism, collimation, intensity distribution, etc. In applications where high quality images are required, these non-uniformities may pose significant problems.

[0168] The phase modulator 14 comprises a diffractive optical element that includes a two-dimensional (2D) array of pixels, each of which is controllable to retard the phase of light incident on the pixel by a selected amount.

[0169] Deviations from ideality of the individual beams 13 can result in non-ideal illumination of the phase modulator 14 (see, e.g., FIG. 1A). For example, individual beams 13 that are not correctly oriented, are not properly collimated, and / or have an undesirable intensity distribution may not provide the desired light field on the phase modulator 14. Non-ideal illumination of the phase modulator 14 can result in non-ideal illumination of the optical system (e.g., projector imager) downstream of the phase modulator 14.

[0170] In some embodiments, the ideal beam 13 is: each of which will illuminate a particular corresponding area of ​​the phase modulator 14; and / or each would illuminate a corresponding area with a particular light distribution (e.g., a uniform light distribution); and / or It will jointly illuminate multiple non-overlapping areas on the phase modulator 14.

[0171] The phase modulator 14 may be controlled to combine multiple beams 13 to illuminate a downstream optical system, as described herein, and in doing so, may be controlled to compensate for some or all of the deviations of the beams 13 from ideality, as discussed above.

[0172] One aspect of the technology described herein provides systems and methods for correcting non-uniformity in beams 13. In some embodiments, each beam 13 illuminates a corresponding separate region of phase modulator 14. Each region of phase modulator 14 may be controlled to provide a patch lens having an optical shape that corrects a particular non-uniformity present in the corresponding beam 13. The optical shapes applied to correct different beams 13 may be different.

[0173] The optical shape of the patch lens for each beam 13 may be based on the measured deviation of the corresponding beam 13 from ideal and / or the deviation of the light field produced at the image plane after the beam 13 interacts with the phase modulator 14 from ideal.

[0174] The individual beams 13 may have variations in pointing parallelism and / or variations in collimation uniformity. The deviations of the individual beams 13 from ideal may be measured for each beam. Based on the measured deviations, an optical shape of the patch lens designed to correct the measured non-uniformity may be generated. The phase modulator 14 may be controlled to display the generated optical shape.

[0175] As shown in FIG. 2A, each individual beam 13 illuminates a corresponding area of ​​the active surface 14A of the phase modulator 14. If one or more multi-emitter light sources 12 comprise N light sources, and thus there are N corresponding beams 13, then the active surface 14A may be divided into N corresponding areas (e.g., areas 15-1, 15-2, 15-3, ..., 15-N-1, 15-N (collectively areas 15)). Each area 15 may be individually controlled to display a "patch lens" 15A having a corresponding optical shape designed to correct deviations from ideal present in the corresponding beam 13. The patch lenses 15A displayed by different areas 15 may be the same or different. In the figures, the patch lenses 15A are sometimes shown diagrammatically as spaced apart circular shapes. However, the patch lenses 15A may cover areas of other shapes (e.g., rectangular areas 15), and adjacent patch lenses 15A may abut each other. In some embodiments, the entire active area 14A of the phase modulator 14 may be covered by multiple patch lenses 15A.

[0176] FIG. 2B shows diagrammatically an area 15 of the active surface 14A of the phase modulator 14 displaying a patch lens 15A.

[0177] The optical shape of each patch lens 15A may be generated independently. By generating the optical shape of each patch lens 15A independently, the optical shapes can advantageously correct for deviations from the ideal, such as non-uniformities present in the individual beams 13 for which the optical shapes are generated. The optical shapes may be designed to correct, for example, for varying pointing parallelism and / or varying collimation uniformity of the beams 13.

[0178] The phase patterns corresponding to the individual patch lenses 15A may be generated, for example, by optimization processes described herein. These processes may, for example, observe characteristics of an output beam or a portion of an output beam corresponding to a particular one of the beams 13. The processes may iteratively vary the phase displacement of the corresponding patch lens 15A until the observed characteristics of the output beam indicate that the patch lens 15A is adequately correcting the deviation of the individual beam 13 from ideal. Such processes may be performed sequentially and / or in parallel for all of the individual beams 13. An exemplary process for generating the phase patterns of the patch lenses 15A is described below with reference to FIG. 12.

[0179] The optimization process may vary depending on what form, if any, is assumed for the phase shift corresponding to patch lens 15A. In some embodiments, patch lens 15A does not have a predefined shape. In such embodiments, optimization may be performed for multiple possible phase shifts for every pixel of region 15 to find a pattern of phase shift that appropriately corrects the deviation of the corresponding individual beam 13 from ideal. Such a process may apply an optimization approach such as simulated annealing to find the phase shift of region 15 that will make up the phase pattern of the corresponding patch lens 15.

[0180] In some embodiments, the patch lenses 15A are specified by a parameterized lens model. The parameterized model may include parameters that specify factors such as focal length, optical center shift, parameterized astigmatism, tilt, etc., for the corresponding patch lens 15A. For a particular set of these parameters, the model may output a phase pattern for the corresponding patch lens 15A. The phase pattern may specify a phase shift to be applied to each pixel of the corresponding region 15 of the phase modulator 14.

[0181] In the case where the patch lens is specified by a parameterized lens model, optimization may be performed on multiple parameters of the lens model to find a set of parameters that specifies a patch lens 15A that appropriately corrects the deviations of the corresponding individual beams 13 from ideal.

[0182] In some embodiments, each region 15 may be divided into multiple sub-regions, and a patch lens 15A is specified by a parameterized lens model for each of the multiple sub-regions. The patch lens 15A applied to such regions may have different portions corresponding to each sub-region (e.g., portions 15A-1 and 15A-2 in FIGS. 2D and 2E). In some such embodiments, the boundaries of the sub-regions are also parameterized. In such embodiments, the optimization may include one or more of: determining whether to specify separate parameterized lens models for the different sub-regions, determining parameters that determine the location of one or more boundaries of the sub-regions, and determining parameters of the parameterized lens model that corresponds to each of the multiple regions.

[0183] In such an embodiment, different portions of a single beam 13 may illuminate two or more sub-regions of a corresponding region 15. The phase pattern in each of the multiple sub-regions may be set to emulate a lens with different characteristics. FIGS. 2D and 2E are non-limiting examples. The parameters of the lens model (e.g., focal length, center position, size, tilt) may be specified independently for two or more sub-regions defined by one or more boundaries 19. The boundary 19 may be defined by parameters such as the location of multiple endpoints or the shape of the boundary between multiple endpoints. In some embodiments (see FIG. 2E), the boundary 19 includes a closed shape. For such a boundary 19, the parameters may include the center position, a parameter specifying the shape of the boundary (e.g., the degree of decentering), a parameter specifying the diameter or size of the sub-region within the boundary 19, and the like.

[0184] 2E is an example of a case where two subregions may be defined by a single subregion: parameters of one lens model may be fitted to the inside of boundary 19, and parameters of another lens model may be fitted to the subregion outside boundary 19.

[0185] In some cases, the optical shape (pattern of phase shifts) in one sub-region can be considered to correspond to multiple lenses (e.g., spherical lenses) superimposed on one another (e.g., the phase pattern of a sub-region may be achieved or understood as a smaller lens superimposed on a portion of a larger lens). In some cases, the displayed optical shapes correspond to multiple separate lenses (e.g., multiple lenses in adjacent sub-regions) illuminated by the same beam 13.

[0186] 2F illustrates another exemplary case in which a lens model may be adapted to correct deviations from ideal in different portions of a single beam 13. In the embodiment illustrated in FIG. 2F, some beams 13 are large enough to extend over two regions 15 (see, e.g., beam 13-3). For these beams 13, each of two or more patch lenses 15A may be configured to correct deviations from ideal in a corresponding portion of beam 13.

[0187] The pixels of the active surface 14A of the phase modulator 14 corresponding to a particular region 15 may be controlled to do the following: displaying an optical shape corresponding to patch lens 15A (optionally having two or more sub-regions in which multiple phase patterns are individually optimized); and / or Displaying different optical geometries corresponding to different patch lenses 15A for different groups of pixels (eg beam 13 illuminates two or more patch lenses 15A).

[0188] The patch lenses 15A may be specified at different times in the life of the apparatus described herein. For example, the patch lenses 15A may be specified during an initial calibration performed when the apparatus is new or still in manufacture. The patch lenses 15A may also be specified as part of a field calibration when the apparatus described herein is first installed in a new location. The field calibration may correct for misalignments that may occur as a result of shipping or installation and / or beam 13 problems resulting from the environment in which the apparatus is installed. The patch lenses 15A may be refined as part of a power-on routine of the apparatus described herein and / or as part of a selectable calibration routine.

[0189] In some embodiments, the optical shape of one or more patch lenses 15A is controlled in real time to take into account changing characteristics of beam 13 (eg, time-varying misalignment of light source 12 with phase modulator 14). [Combination of compensation and light guidance]

[0190] In addition to correcting and combining beam 13, phase modulator 14 may be controllable to steer light to desired locations in the image plane. Light steering may be performed by applying selected patterns of phase delays to light incident on different pixels of phase modulator 14. The portion of light from beam 13 that is diffracted, or "steered," in one or more desired directions exits phase modulator 14 as steered light 16.

[0191] The deviations from ideality of the beams 13 discussed above, if left uncorrected, can result in multiple portions of directed light 16 arising from different beams 13 that are not properly aligned. For example, consider the case where it is desired to create a very bright highlight by controlling the phase modulator 14 to concentrate the directed light from all of the multiple beams 13 to the same small area or spot in the image plane.

[0192] As shown in Fig. 1, deviations of the beams 13 from ideal can cause the directed light 16 resulting from the different beams 13 to be focused at different distances from the image plane and / or directed to different locations on the image plane, instead of all being focused in the same way at the same location on the image plane. The change in focus can result in an overall larger point spread function (PSF) of the directed light 16, and can result in the final image being out of focus or containing undesirable artifacts. The same problem exists if it is intended to direct light to different locations on the image plane and / or to direct the light resulting from some beams 13 differently than the light resulting from other beams 13.

[0193] If light steering is desired, the optical geometry applied to each of the multiple beams 13 may additionally include a phase shift to generate the desired guided light. The optical geometry may, for example, include a patch lens component 15A that corrects the corresponding beam 13, and a light steering component. The patch lens component and the light steering component may be superimposed (e.g., by adding the phase shifts specified by each of the patch lens component and the light steering component, which may be modulo 2π or a multiple of 2π such that the resulting phase shift is within the range of the phase modulator 14). Thus, the optical geometry provided by the phase modulator 14 may simultaneously correct non-uniformities in the multiple beams 13 and steer the multiple light beams 13.

[0194] The light directing components applied to the different beams 13 may be the same or different. For example, in some embodiments, it is desired to direct light to one or more highlights, and the light directing components for each of the beams 13 are configured to direct light to each of the one or more highlights. As another example, in some embodiments, it is desired to direct light to a plurality of different highlights, and the light directing components for different ones of the beams 13 are configured to direct light to different subsets of the plurality of highlights. In some embodiments, the different subsets of the plurality of highlights are distinct. In some embodiments, at least some of the different subsets of the plurality of highlights include a common highlight. In some embodiments, the light directing components are configured to direct the beams 13 to focus on a plurality of different points. For example, some of the beams 13 may be directed to focus on a first point, some of the beams 13 may be directed to focus on a second point, and some of the beams 13 may be directed to focus on a third point, where the first point, the second point, and the third point are different points.

[0195] In some embodiments, each region 15 is individually controlled to display a pattern of phase shifts that directs light from a corresponding beam 13 to generate directed light 16. Light from a beam 13 may be directed to concentrate the light in a particular area of ​​the image plane (said to be directed toward such area). Light from a beam 13 may also be directed to provide less light to a particular area of ​​the image plane (said to be directed away from such area). The area to which the light is directed may have a light intensity that is well above the maximum intensity that would be possible if all of the light from the multiple beams 13 were distributed uniformly over the image area of ​​the image plane. Multiple beams 13 may be directed to one or more different areas. For example, multiple beams 13 may be directed to the same area. For example, some of the multiple beams 13 may be directed to a first area and other beams 13 are directed to a second, different area.

[0196] Light steering may be applied to producing high dynamic range images for cinema, displaying technical or medical images, and / or industrial processing. Light steering may be controlled in response to image data such that light is directed toward areas where the image data specifies a higher brightness and / or away from areas where the image data specifies a lower brightness level. Light steering may beneficially help to accurately generate images where there are large variations in brightness specified for different locations in the image. For example, light steering may help to generate natural images of scenes such as sunlight shining on water, bright stars of various sizes in a dark night sky, a sunset with a shadow in the foreground, etc.

[0197] FIG. 2C shows an optical arrangement 10 in which the phase modulator 14 is controlled to correct deviations of the multiple beams 13 from the ideal and to direct light from each beam 13 such that the light from all of the multiple beams 13 is focused at a focal point 18. As shown in FIG. 2C, the correction applied by the patch lens makes it easier to direct the directed light 16 resulting from all of the multiple beams 13 to focus at the focal point 18 (or, more generally, to have any other desired distribution on the image plane). The more comprehensively the deviations of the beams 13 from the ideal are corrected, the more accurately the directed light 16 resulting from the different beams 13 can be registered together (e.g., to focus at a single focal point 18 or to be precisely directed to different highlights at specific locations on the image plane). Precise registration of the directed light 16 resulting from the different beams 13 is advantageous because a well-focused and precise highlight image can be generated by illuminating a projector imager (or other downstream optics) with such light.

[0198] The optical geometry of patch lens 15A and the phase shift for light steering may be calculated independently of each other. In other embodiments, the optical geometry of patch lens 15A and the phase shift for light steering may be calculated together. The phase shifts for patch lens 15A and the light steering components may be superimposed. Thus, the correction of deviations from ideal present in beam 13 and the light steering of beam 13 may occur simultaneously.

[0199] 3 is a block diagram that generally illustrates an exemplary optical arrangement 20. A multi-emitter light source 12 generates a raw illumination light field 21 (e.g., beam 13). As described elsewhere herein, the raw illumination light field 21 may include multiple non-ideal light beams having varying characteristics, such as varying pointing parallelism, varying collimation uniformity, etc. The raw illumination light field 21 is directed into a light redistributor module 22.

[0200] The light redistribution module 22 comprises a phase modulator 14 illuminated by the raw illumination light field 21. The phase modulator 14 receives as input a control signal that sets the phase delay applied by individual pixels of the phase modulator 14 to provide a specified phase pattern. A controller 25 generates the light steering components of the phase pattern by the light redistribution scheme 23. The light redistribution scheme 23 may, for example, process image data to generate a pattern of phase shifts that will direct light towards higher luminance regions defined in the image data and / or away from lower luminance regions defined in the image data.

[0201] The light redistributor module 22 may direct the guided light to the input of a downstream optical system (e.g., toward a projector imager to illuminate the imaging plane of the projector imager). The light redistribution scheme 23 may incorporate methods described, for example, in International PCT Publication No. WO2015054797A1, entitled LIGHT FIELD PROJECTOR AND METHOD, International PCT Publication No. WO2016015163A1, entitled NUMERICAL APPROACH FOR FREEFORM LENSES: AREA PARAMETERIZED FREEFORM LENSES, and International PCT Publication No. WO2015184549A1, entitled EFFICIENT, DYNAMIC, HIGH-CONTRAST LENSES FOR IMAGING, ILLUMINATION AND PROJECTION APPLICATIONS, which are hereby incorporated by reference herein for all purposes.

[0202] In addition, the controller 25 preferably receives or acquires light source characteristic data 24 that provides characteristics of the light field (e.g., raw illumination light field 21) illuminating the phase modulator 14. The characteristics may include directional orientation and / or collimation information of the light field (e.g., characteristics of the beams 13 that contribute to the light field). The controller 25 may process the light source characteristic data 24 to generate an optical shape of the patch lens 15A displayed by the phase modulator 14 to correct deviations from ideal of the light field 21 illuminating the phase modulator 14. The light source characteristic data 24 may be acquired by measuring characteristics of the light field (e.g., beam 13) emitted from the light source 12 during a calibration procedure and / or in real time when the light redistributor module 22 is operating.

[0203] The phase shift of the patch lens 15A and the light guidance may be superimposed, so that the correction of the raw illumination light field 21 and the guidance of the raw illumination light field 21 may occur simultaneously.

[0204] A portion of the raw illumination light field 21 is output as directed light 16 (e.g., to illuminate the imaging plane of a projector imager). As discussed elsewhere herein, a portion of the raw illumination light field 21 may be directed to one or more different points or areas. Another portion of the raw illumination light field 21 exits the light redistributor module 22 as undirected light 17.

[0205] In some embodiments, the light redistributor module 22 includes a receiving optics 26 upstream of the phase modulator 14. The receiving optics 26 may shape or modify the raw illumination light field 21 to better illuminate the phase modulator 14. For example, the raw illumination light field 21 may be wider than the active surface 14A of the phase modulator 14. The receiving optics 26 may shape the raw illumination light field 21 so that the raw illumination light field 21 matches the size of the active surface 14A of the phase modulator 14. Additionally or alternatively, the receiving optics 26 may align the raw illumination light field 21 with the active surface 14A of the phase modulator 14. In such an embodiment, the shaped illumination light field 27 illuminates the phase modulator 14. [Use of unguided light]

[0206] Most or all practical phase modulators cannot phase modulate all the incident light. It is virtually inevitable that the phase modulator will output at least some unguided light. For example, if the phase modulator 14 is a reflective phase modulator, some light will typically be specularly reflected from multiple faces of the phase modulator. This results in unguided light 17. The ratio between the guided light 16 and the unguided light 17 may depend on the diffraction efficiency of the phase modulator 14.

[0207] In some embodiments, phase patterns selected to cause specular reflection of some or all of the light from beam 13 may be displayed to increase the amount of unguided light available. This may be done, for example, at times when a highlight image is not needed and / or when the highlight image does not require as much optical power and / or when additional background illumination is needed.

[0208] For example, if a highlight image is not required, all of the pixels in active area 14A, or all of the pixels in a portion of active area 14A illuminated by beam 13, may be set to display a pattern of phase shifts that causes specular reflection of light from beam 13.

[0209] In cases where it is desired to retain some of the guided light, individual regions 15, or portions of some or all of the regions 15, may be configured to display a pattern of phase shifts that cause specular reflection of light incident thereon. The retaining regions 15 and / or portions of the regions 15 may be configured to display a phase pattern that causes the desired light guidance of the guided light components. By increasing the amount of unguided light, the intensity of the base illumination may be increased. This may result in increased efficiency, reduced power consumption, etc. of the projection system. In some embodiments, the size (e.g., surface area) of one or more patch lenses 15A is reduced, and the pixels of the corresponding regions 15 that no longer display the optical shape associated with the patch lenses 15A are configured to display a pattern of phase shifts that cause specular reflection to increase the amount of unguided light.

[0210] In some embodiments, the percentage of incident light that is reflected as unguided light (and thus how much light becomes guided light) is determined during a calibration step, and in some cases, the percentage is based at least in part on the power levels of the individual light-emitting elements 12.

[0211] It may be desirable to separate the guided light from the unguided light, thereby facilitating separate control of the guided and unguided light. For example, it may be desirable to collect the unguided light in a light path and shift the direction of the guided light 16 so that it does not enter the light path of the unguided light 17.

[0212] In some embodiments, separation of the guided and unguided light is created or increased by shifting the direction of the guided light 16 relative to the unguided light 17. Such a shift may be created by the light guiding component and / or the patch lens component of the phase pattern applied by phase modulator 14.

[0213] As described elsewhere herein, the unguided light 17 may be focused to a spot adjacent an input diffuser (e.g., input diffuser 47 described elsewhere herein) near the input of the homogenization and / or recombination optics 42. Increasing the angle at which light is guided by the phase modulator 14 generally reduces efficiency, so it is desirable to have a relatively small angular separation between the guided light 16 and the unguided light 17.

[0214] In some embodiments, the lateral separation between the points at which the guided light 16 and the unguided light 17 are focused is less than 100 mm, or less than 60 mm, or less than 10 mm.

[0215] In some embodiments, both directed light 16 and undirected light 17 are directed to an image plane. For example, undirected light 17 may provide a base level of illumination to an image area at the image plane, and directed light 16 may provide a highlight image that increases the light intensity in a portion of the image area that corresponds to a highlight.

[0216] 4 illustrates generally an optical arrangement 30 that may be applied to direct both guided light 16 and unguided light 17 to an image plane. Optical arrangement 30 is the same as optical arrangements 10 and 20, except that optical arrangement 30 includes a physical lens 32. Physical lens 32 may be positioned to maximize incidence of guided light 16 and unguided light 17 onto physical lens 32. Physical lens 32 focuses unguided light 17 to focal point 33A. Guided light 16 is focused to focal point 33B.

[0217] In optical configuration 30: The directionality of the unguided light 17 depends on the properties of the physical lens 32; and The directionality of the guided light 16 depends on both the properties of the physical lens 32 and the phase pattern displayed by the phase modulator 14 (e.g., the patch lens 15A displayed by the phase modulator 14 and the light guiding components displayed by the phase modulator 14).

[0218] Once both the guided light 16 and the unguided light 17 are focused, they may be combined together into a single light field. Combining the guided light 16 and the unguided light 17 may advantageously produce the following results: ·Improved overall brightness in the projected image; · improved efficiency of use of the light emitted by the light source 12; · reduced performance requirements for dissipating (e.g. absorbing) energy from unused light emitted by light source 12; etc.

[0219] 5 illustrates generally optical arrangement 40 configured to combine guided light 16 and unguided light 17. Optical arrangement 40 may be the same as optical arrangement 20 described elsewhere herein, except that optical arrangement 40 additionally comprises homogenization and / or recombination optics 42 that generate output optics light field 43.

[0220] The homogenization and / or recombination optics 42 receive the guided light 16 and the unguided light 17 and combine the guided light 16 and the unguided light 17 into a light field that is output from the homogenization and / or recombination optics 42 as an output light field 43.

[0221] The output light field 43 may, for example, illuminate a projector imager (or other downstream optics for generating an image). In some embodiments, the output light field 43 generated by the homogenization and / or recombination optics 42 efficiently couples to a projector imager or other downstream optics. In some embodiments, the homogenization and / or recombination optics 42 is configured to generate a light field having an appropriate shape, propagation direction, angle of incidence, etc., for the output optics light field 43 to efficiently couple to the downstream optics. Preferably, the homogenization and / or recombination optics 42 is optimized to minimize light loss, maximize beam quality of the output optics light field 43, minimize the number of optical components in the downstream optics, etc.

[0222] The homogenization and / or recombination optics 42 operates to combine the guided light 16 and the unguided light 17. The homogenization and / or recombination optics 42 also: · Homogenizing the unguided light 17; forming an output optical system light field 43; and Diffusion of one or both of the guided light 16 and the unguided light 17; may perform one or more of the following:

[0223] An exemplary homogenization and / or recombination optics 42 is shown diagrammatically in Figure 6. In the embodiment of Figure 6, a combining rod 44 serves to receive and combine the guided light 16 and the unguided light 17. The combining rod 44 may additionally serve to homogenize the unguided light 17.

[0224] The homogenization and / or recombination optics 42 optionally include one or more diffusers operable to diffuse the guided light 16 and / or the unguided light 17. For example, the homogenization and / or recombination optics 42 may include: · a diffuser 46 in the path of the guided light 16 upstream of the coupling rod 44 to diffuse the guided light 46A; a diffuser 47 in the path of the unguided light 17 upstream of the coupling rod 44 to diffuse the unguided light 47A; and / or a diffuser 48 downstream of the combining rod 44 to diffuse the combined light field 43; may include one or more of:

[0225] The inclusion of one or more of diffusers 46, 47, and 48 may advantageously assist in eliminating laser speckle, producing a more uniform light field, producing a desired divergence angle (i.e., the desired divergence angle of the light exiting the homogenization and / or recombination optics 42), etc.

[0226] 7 shows a schematic of optical arrangement 50. Optical arrangement 50 is similar to optical arrangement 30 described elsewhere herein, except that optical arrangement 50 comprises homogenization and / or recombination optics 42 that includes a coupling rod 44. Coupling rod 44 is positioned to homogenize unguided light 17 and pass guided light 16 to an output light field 43.

[0227] The guided light 16 is directed into the end 44A of the coupling rod 44 (which may be referred to as an "entrance opening" even though the end 44A does not physically have a hole or bore), passes through the body 44B of the coupling rod 44, and exits through the second end 44C of the coupling rod 44 (which may be referred to as an "exit opening" even though the end 44C does not physically have a hole or bore). The guided light 16 is directed towards the coupling rod 44 in a direction that ensures that the guided light 16 does not enter a reflective surface of the coupling rod 44. In this example, the guided light 16 is not reflected within the coupling rod 44. For example, the guided light 16 may be directed along the central axis of the coupling rod 44. In such an embodiment, the coupling rod 44 does not modulate the guided light 16. The pattern of high and low brightness areas resulting from directing the guided light 16 is preserved in the output light field 43.

[0228] In contrast to the guided light 16, the unguided light 17 is directed towards the coupling rod 44 in a manner that causes the unguided light 17 to undergo multiple internal reflections within the coupling rod 44. These reflections tend to homogenize the unguided light 17.

[0229] In the embodiment of FIG. 7, the coupling rod 44 is tapered and the lens 32 directs the unguided light 17 to enter near the edge of the first end 44A and / or in a direction angled toward side 44D of the coupling rod 44, so that the unguided light is internally reflected by side 44D and then internally reflected several times inside the coupling rod 44 before exiting the second end 44C.

[0230] The unguided light 17 is optionally diffused by a diffuser 47 before reaching the coupling rod 44 .

[0231] The unguided light 17 is coupled with the guided light 16 in the coupling rod 44. Reflection of the unguided light 17 from the inner surface of the coupling rod 44 changes the propagation axis of the unguided light 17 so that it is aligned with the propagation axis of the guided light 16.

[0232] The combined, guided light 16 and unguided light 17 may optionally be diffused with an output diffuser 48 to produce a desired light field 43 for downstream output. In some embodiments, a lens 52 focuses the combined, guided light 16 and unguided light 17 onto a projector imager or other downstream optics.

[0233] In some embodiments, coupling rod 44 is a passive optical device. Coupling rod 44 may be configured to direct unguided light 17 in approximately the same direction as guided light 16 while varying optical properties such as the number of reflections, input and output beam angles, etc. to create a more uniform light pattern for unguided light 17.

[0234] The coupling rod 44 may be designed to maximize the amount of light it can receive from the phase modulator 14. Maximizing the amount of light it can receive is advantageous because it increases the efficiency of the light utilization of the system. The shape and / or profile of the reflective and / or scattering inner surface of the coupling rod 44 may be designed to provide at least a threshold number of reflections to achieve a desired degree of homogenization of the unguided light 17.

[0235] In some embodiments, rod 44 has two reflective flat surfaces that taper from a larger input face (allowing separate guided light 16 and unguided light 17 to be collected) to an output face that is smaller than the input face, so that guided light 16 and unguided light 17 are spatially overlapped.

[0236] The exit aperture of the coupling rod 44 (e.g., end 44C) may be designed to output light at an appropriate range of angles to produce a desired output light field. The exit angle of the output light may be kept small (e.g., less than 45°) to reduce the size of any downstream collection optics. For example, the exit aperture of the coupling rod 44 may be designed to output light that is incident on downstream output optics at a range of angles of incidence within the acceptance angle of the downstream output optics.

[0237] The design of the connecting rod 44 is: the cone through which light enters the coupling rod 44; and / or the angle of incidence of the light; and / or the length of the connecting rod 44; and / or the angle of the connecting rod 44 (e.g., the angle at which the connecting rod 44 is tapered); and / or -Light emission angle, These factors may be optimized to reduce cost and / or size (e.g., by making the coupling rod 44 shorter) and / or for the quality of light at the output of the coupling rod 44 (e.g., a symmetrical output with relatively little divergence).

[0238] In some embodiments, the coupling rod 44 is configured to provide a substantially symmetric output (e.g., the axis of the exit divergence of the light exiting the coupling rod 44 is aligned (e.g., parallel) with the axis (e.g., central longitudinal axis) of the coupling rod 44.

[0239] If it is desired to reduce the divergence of the light leaving the coupling rod 44, the coupling rod 44 may be made longer.

[0240] In some embodiments, the coupling rod 44 is configured such that the unguided light 17 entering the coupling rod 44 undergoes multiple reflections before exiting the coupling rod 44 (thus promoting homogenization of the unguided light 17) while having a relatively small exit angle of the light at the exit aperture of the coupling rod 44 (e.g., angle θ shown in FIG. 7A). Minimizing the exit angle of the light at the exit aperture may advantageously facilitate increasing the amount of output light captured by downstream optics. By reducing the exit angle of the light at the exit aperture to a smaller (and therefore less expensive) downstream optics (e.g., optics 52) may be used to capture the output light.

[0241] In some embodiments, the coupling rod 44 comprises a hollow tube (see, e.g., FIG. 7A). The interior surface of the wall of the coupling rod 44 may include a reflective material, such as a deposited layer of a reflective metal or a dielectric coating.

[0242] The guided light 16 may be directed in a direction parallel to the central longitudinal axis extending through the hollow tube, so that the coupling rod 44 does not significantly affect the guided light 16. In contrast, the unguided light 17 may be multiplied, reflected and / or scattered by the reflective material on the inner surface of the wall. Through repeated reflections and / or scattering, the unguided light 17 may be homogenized and redirected to exit the coupling rod 44 where it is combined with the guided light 16.

[0243] 7A, a prism 45 may be optically coupled proximate to a first face 44A of the coupling rod 44. The prism 45 may collect the unguided light 17 and efficiently transmit the unguided light 17 to the coupling rod 44.

[0244] In some embodiments, the coupling rod 44 comprises a solid of a transparent material, such as glass, quartz, or a suitable transparent plastic. In such embodiments, the unguided light 17 may be totally internally reflected off multiple surfaces of the solid, and / or the solid may include a light-reflecting and / or light-scattering layer or coating. The unguided light 17 is directed to enter the first end 44A (e.g., "entrance aperture") of the coupling rod at an angle such that the unguided light 17 is incident on the side of the coupling rod 44 at an acute angle relative to a vector normal to the side. The guided light 16 may enter the body 44B of the coupling rod 44 and pass through the coupling rod 44 without interacting with the multiple sides of the coupling rod 44, resulting in the guided light exiting the coupling rod 44 intact towards the projector imager and / or other downstream optics. In such embodiments, the coupling rod 44 redirects the unguided light 17 to exit the coupling rod 44 (e.g., from the second end 44C or “exit aperture”) propagating in approximately the same direction as the guided light 16. In some embodiments, the cross section of such a coupling rod 44 is rectangular and has an aspect ratio that matches the aspect ratio of the image generated from the guided light 16.

[0245] In some embodiments, the coupling rod 44 comprises a hollow rectangular tube having at least one tapered surface (see, e.g., FIG. 7B). The hollow rectangular tube may be tapered toward the downstream optics (i.e., the cross-sectional area of ​​the hollow rectangular tube hole may be tapered from the hollow rectangular tube's entrance opening to the hollow rectangular tube's exit opening). The hollow rectangular tube may have a larger entrance opening than the exit opening. Having a larger entrance opening increases the amount of incoming light (e.g., unguided light 17, guided light 16, etc.) that can be received by the coupling rod 44. As a result of having a smaller exit opening than the entrance opening, the coupling rod 44 will produce a more concentrated output light field compared to the case where the entrance and exit openings are the same size.

[0246] In some embodiments, the coupling rod 44 is tapered in one plane (e.g., along either the horizontal axis of the coupling rod 44 or the vertical axis of the coupling rod 44). Light may enter the coupling rod 44 from one or both optical axes. Unguided light 17 is directed to be incident on the reflective side walls of the coupling rod 44 and is reflected between a pair of side walls. In some embodiments, the coupling rod 44 is tapered in both the horizontal and vertical axes. In such embodiments, unguided light 17 may enter the coupling rod 44 along either axis of the coupling rod 44. The homogeneity of the unguided light 17 may be increased by reflection off multiple internal horizontal and vertical surfaces.

[0247] In some embodiments, the coupling rod 44 is a twisted rod. In such embodiments, the unguided light 17 may be reflected off of multiple different internal surfaces of the twisted coupling rod 44. Reflection off of multiple different internal surfaces may increase the homogeneity of the unguided light 17. In such twisted rods, the guided light 16 passes through the central axis of the rod unmodified. The cross section of the twisted portion is larger than the extent of the guided light 16. The extent of the twist may be, for example, about a quarter turn (e.g., 90°) to several turns (e.g., 180°, 270°, 360°, etc.) to increase the homogeneity of the unguided light 17.

[0248] In some embodiments, the inner wall of the coupling rod is a custom freeform concave shape (see, e.g., FIG. 7C ). The custom freeform concave shape may be optimized to produce the appropriate reflection angle to maximize the amount of incident light (both guided light 16 and unguided light 17) present at the exit aperture of the coupling rod in the appropriate angular range to be received by downstream optics, while providing a desired amount of homogeneity of the unguided light 17.

[0249] In some embodiments, additional light (e.g., a "base illumination beam") may be combined with the guided light 16 and / or the unguided light 17. The light from the base illumination beam may increase the intensity of the light incident on the projector imager (or other downstream optics). For example, the base illumination beam may be directed into a combining rod 44. The base illumination beam may be combined with the unguided light 17 at the combining rod 44. In some embodiments, the base illumination beam adds uniformly to the illumination in the output light field 43.

[0250] In some embodiments, the intensity of the base illumination beam is adjustable. The adjustment may be achieved, for example, by one or more of: adjusting the output intensity of one or more light sources providing the light of the base illumination beam; passing the base illumination beam through an adjustable aperture; pulsing the base illumination beam with a variable duty cycle; passing the base illumination beam through a rotatable polarizer; and modulating the base illumination beam with an optical modulator. In some embodiments, the base illumination beam is modulated with a reconfigurable separator device (e.g., a variable polarizer or beam splitter). In some embodiments, the base illumination beam is modulated with a reconfigurable optical illumination device.

[0251] In some embodiments, the base illumination beam, the guided light 16, and the unguided light 17 are controlled based on characteristics of the image data according to a scheme such as that described in PCT Publication WO2015172236A1, entitled Optimizing Driving Schemes for a Multiple Projector System, which is hereby incorporated by reference herein for all purposes.

[0252] Providing a base illumination beam through an optical path that does not include the phase modulator 14 can help display a projected image with a greater average brightness than can be reliably provided using light from the phase modulator 14 alone. This is because there is generally a limit to the optical power that the phase modulator 14 can handle. A typical phase modulator absorbs some incident light. This can result in heating of the phase modulator. Illuminating such a phase modulator with too much light can heat it to a temperature that causes damage. High intensity light can also degrade certain types of phase modulators through photochemical effects. In general, it is desirable to limit the light transmitted to the phase modulator 14 to have no more than a practical maximum light intensity. The maximum light intensity may be selected based on the thermal properties of the phase modulator 14, the wavelength of the incident light, and / or the desired life of the phase modulator 14.

[0253] In some embodiments, the base illumination beam has greater optical power than the light illuminating the phase modulator 14 .

[0254] In some embodiments, some light from beam 13 is used to provide the base illumination beam.

[0255] FIG. 8 shows a schematic diagram of an exemplary optical arrangement 60. The optical arrangement 60 comprises a mirror 62 (or other optical deflector) located adjacent to the phase modulator 14 (see, for example, FIG. 8A). The mirror 62 may be located in the plane of the active surface 14A of the phase modulator 14. By locating the mirror 62 in the plane of the active surface 14A of the phase modulator 14, the light reflected by the mirror 62 has the same direction as the unguided light 17 reflected by the phase modulator 14. The mirror 62 may be parallel to the phase modulator 14. The mirror 62 may be adjacent to one or more edges of the phase modulator 14. In some embodiments, the mirror 62 partially covers the active surface 14A of the phase modulator 14.

[0256] Mirror 62 reflects light beam 13 incident on mirror 62. The light reflected by mirror 62 may be used as a base illumination beam 64. Base illumination beam 64 may be directed approximately parallel to unguided light 17.

[0257] In some embodiments, mirror 62 is replaced with another optical element, such as a prism, that extracts some light from beam 13 for use as base illumination beam 64. Such an optical element does not necessarily have to be in the plane of active surface 14A of phase modulator 14. However, base illumination beam 64 and undirected light 17 preferably have the same direction.

[0258] In some embodiments, the base illumination beam 64 is combined with the unguided light 17 at a combining rod 44. The combining rod 44 may combine the base light 64, the unguided light 17, and the guided light 16 together. In some embodiments, the face of the mirror 62 is shaped and / or positioned relative to the phase modulator 14 to introduce the base illumination beam 64 into the combining rod 44 at a desired angle or otherwise direct the base illumination beam 64 into a light path that mixes light from the base illumination beam 64 into the output light field 43.

[0259] 9 is a block diagram that illustrates a schematic of an exemplary optical arrangement 70. Optical arrangement 70 is similar to optical arrangement 40, except that optical arrangement 70 includes a light separator 65. Light separator 65 receives raw illumination light field 21 (e.g., beam 13) and splits raw illumination light field 21 into a base illumination beam 64 and a processed illumination light field 66. Processed illumination light field 66 illuminates light redistributor 22. Homogenization and recombination optics 42 combines base light 64, guided light 16, and unguided light 17.

[0260] The light separator 65 may be, for example, a mirror positioned to block a portion of the raw illumination light field 21. In some embodiments, the light separator 65 is a semi-reflective mirror or a prism. In some embodiments, the light separator 65 is a reflective polarizer that redirects light of one polarization state into the base illumination 64 and light of the other polarization state into the processed illumination light field 66.

[0261] In some embodiments, the base illumination beam 64 originates from one or more separate light sources 67. In some such embodiments, the light sources 67 are arranged to directly emit the base illumination beam 64 towards the homogenization and recombination optics 42. This may, for example, facilitate using a different type of light source as the light source 67 than the light source 12 (e.g., the light source 67 may be cheaper, may have a broader light spectrum, or may otherwise be unsuitable for use as the light source 12, etc.).

[0262] 10 is a block diagram that illustrates a schematic of the optical arrangement 72. The optical arrangement 72 is similar to the optical arrangement 70. However, the optical arrangement 72 comprises a light source 67 for generating the base illumination beam 64. The light source 67 may be, for example, an LED or a laser light source.

[0263] In some embodiments, the patch lens 15A may correct small misalignments of the optical components of the light guidance system. By utilizing this possibility, the need for precise alignment of the optical components may be alleviated. This may result in significantly reduced manufacturing and / or maintenance costs. Furthermore, a device adapted to compensate for changes in alignment of the optical components by adjusting the optical shape of the patch lens 15A may have a structure that is lighter and less expensive to manufacture than the bulky and rigid structures that would otherwise be required to maintain precise alignment of the optical components over the life of the device.

[0264] A patch lens 15A that is effective to achieve one or more of the following may be determined by analyzing the light field produced by the systems described herein: Compensate for misalignment of optical components; Compensating for deviations of the beam 13 from ideal; and / or Compensating for differences in the positions of the patches 15 on the phase modulator 14. For example, an automated imaging system combined with a specific computer algorithm may generate an optical shape for the patch lens 15A that provides the correction described above. Such an image may be taken during a calibration stage during manufacture of the projector system or while the projector system is in use. Such a correction may enable an overall sharper image to be projected by the projector system.

[0265] 11 is a block diagram that illustrates a schematic of alignment system 90. Output light field 43 illuminates output optics 92 (e.g., a projector imager) to generate image 93. Output light field 43 may be generated using optical arrangements described elsewhere herein.

[0266] Output optics 92 may include an amplitude modulator and associated projection optics that form a final image 93, for example, on a screen. In some embodiments, output optics 92 includes a relay system that generates an intermediate light induced image that may be monitored, for example, using an automated imaging system.

[0267] The characteristics of the light-induced image 93 (eg, sharpness, intensity distribution, presence of certain artifacts, etc.) depend on the optical geometry of the patch lens 15A.

[0268] The system 90 includes a sensor 94 (e.g., a camera) positioned to collect images of the image 93 (and / or intermediate light-guided images). The images are processed to measure one or more characteristics of the image 93. The captured images and / or data corresponding to the image 93 are provided as input to a control system (e.g., control system 25) or a computer executing an alignment algorithm 95. The alignment algorithm 95 processes the captured data to measure characteristics of the light used to generate the image 93 and determine an optical shape for the patch lens 15A that will improve the quality of the image 93. The alignment algorithm 95 outputs an optical shape for the patch lens 15A that corrects one or more of the problems described above. Such an optical shape may be provided to the control system 25 as part of the light source characteristic data 24. The optical shape of the patch lens 15A may be superimposed with a phase shift for light guidance as part of the light redistributor 22 described elsewhere herein.

[0269] In some embodiments, the spatial light induced components are applied to corresponding regions of the phase modulator while displaying the image 93. The spatial "calibration light induced phase patterns" may be selected to help distinguish between light originating from different beams 13 and / or to generate a light pattern ("test pattern") in the image 93 that reveals the degree to which the corresponding patch lens is correcting the deviation of the corresponding beam 13 from ideal. In some embodiments, the calibration light induced phase patterns are stored in a data store accessible to the control system 25. In some embodiments, the calibration light induced phase patterns include a sequence of different calibration light induced phase patterns that are applied to different regions of the phase modulator during the course of a calibration routine.

[0270] 12 is a block diagram illustrating steps in an exemplary alignment algorithm 95. In block 100, the method 95 generates an initial optical shape for each patch lens 15A. The initial optical shape may be based on information characterizing the particular light source 12 (e.g., model number, number of emitters, emitter type, power level, wavelength, etc.) and / or information characterizing the phase modulator 14 (e.g., number and size of pixels, location of regions 15, aspect ratio, etc.).

[0271] In block 102, an image of the generated pattern 93 (and / or intermediate light guiding images described elsewhere herein) is captured (e.g., using camera 94). Pattern 93 may be, for example, a calibration image that includes specific light guiding components for beam 13. Since patch lenses 15A correspond to individual light beams 13, it is generally desirable to be able to distinguish between portions of pattern 93 that result from different beams 13. There are various ways in which this can be achieved, including: ·Turn on beam 13 one at a time; ·Turn off beam 13 one at a time; · Varying the intensity of one or more of the plurality of beams 13 in a known manner (e.g., with a known frequency); By varying different beam characteristics etc; applying different light guiding components to different areas of the phase modulator 14 corresponding to different light beams 13; and Varying patch lens 15A or another component used to generate the phase pattern applied to region 15 of phase modulator 14 corresponding to beam 13 (e.g., to move or distort or modify portions of pattern 93 resulting from light beam 13 in a known manner). The variation may be periodic. Different patch lenses may be distinguished by varying the optical shape of each patch lens to change the beam pattern at different rates and / or in different directions.

[0272] Characteristics of the image 93 are identified in block 104. The characteristic characteristics include the location, shape, intensity and uniformity of the portions of the pattern 93.

[0273] The characteristic features identified in block 104 are compared to the reference features in block 106. The patch lens 15A is adjusted in loop 109 until the characteristic features detected in block 104 match the corresponding reference features with a desired level of accuracy. If the characteristic features match the reference features, the source characteristic data (i.e., the optical shape of the patch lens) is stored and / or communicated to the phase modulator 14 in block 110.

[0274] If the desired level of accuracy has not been reached, the optical shape and / or position of the patch lens is updated in block 107. The desired level of accuracy typically depends on the image quality required by a particular market segment. For example, the desired level of accuracy may be higher for a professional large cinema system than for a small home entertainment projector.

[0275] Patch lenses are: · Focal length in X direction; · Focal length in Y direction; Location of the optical center of the lens; Lens tilt in X direction; Lens tilt in Y direction; the size of the lenses; and / or the position of the lens area within the region 15 of the phase modulator 14, It may be characterized by factors such as:

[0276] In block 107, one or more of the above factors corresponding to the patch lens can be changed. Usually, one or more factors are changed stepwise to optimize the patch lens. Each iteration preferably produces a more desirable point spread function (PSF) shape and size. The search for the optimized parameters of the patch lens can be a brute force search if there are few enough parameters, or it can be a gradient search, or it can use a simulated annealing approach, or it can address multiple parameters in a certain order.

[0277] In some embodiments, the parameters of the patch lens are optimized by: starting with a reference patch lens configuration (e.g., a spherical lens with a selected focal length), moving the center of the patch lens to find the best center position, optionally adjusting the tilt of the patch lens, and then adjusting one or both of the lens focal length and size.

[0278] The updated optical shape is communicated to the phase modulator 14 in block 108 and the method 95 returns to block 102 where a new image of the pattern 93 is taken. The new image is generated using the updated optical shape and / or position of the patch lens 15A. The loop 109 will repeat until a desired level of accuracy is reached.

[0279] In some embodiments, each patch lens is determined sequentially (ie, one patch lens at a time).

[0280] In some embodiments, different patch lenses are determined simultaneously (i.e., two or more patch lenses are determined simultaneously). This increases efficiency and reduces computation time. Each patch lens only affects the light from the light beam 13 that is incident on that particular patch lens, and therefore only the light distribution on the screen that is due to that patch. By identifying which patch lens corresponds to which screen spot, it is possible to simultaneously change parameters of different ones of the patch lenses. Identifying which patch lens corresponds to which screen spot may be done, for example, by updating the different patch lenses in different directions or at different speeds, and correlating the changes with changes observed in the pattern 93 on the screen.

[0281] 13 illustrates generally an exemplary method 115 for improving the alignment of multiple optical elements in a projector system. Method 115 is similar to method 95, except that method 115 may optimize multiple patch lenses simultaneously, which may increase time efficiency.

[0282] Method 115 determines which features of pattern 93 correspond to each patch lens 15A, for example by using any of the approaches described above.

[0283] In block 116, an initial optical shape of the plurality of patch lenses (e.g., patch lens 15A) is generated. The initial optical shape of the plurality of patch lenses may be determined from known optical parameters of the product design. For example, the optical shape may be determined given the initial positions of the illumination patches and the designed focal length.

[0284] An image of the pattern 93 is captured (e.g., using the camera 94) in block 117. In block 118, the captured image data is processed to identify features that correspond to individual ones of the plurality of patch lenses 15A or sets of the plurality of patch lenses. In block 119, the identified features are matched to the corresponding patch lenses 15A.

[0285] As described elsewhere herein, identifying which patch lens corresponds to which on-screen spot may be done by updating multiple different patch lenses, for example in different directions or at different rates, and correlating the changes with changes observed in the image on the screen. In some embodiments, a single patch lens is altered and a corresponding change is observed.

[0286] A single patch lens may potentially direct light to any point on the screen, so it may be necessary to identify which features on the screen (across the screen) correspond to which patch lens.

[0287] The identified features are compared to the corresponding reference features. Block 120 determines whether the identified features match the corresponding reference features with a threshold accuracy. If the threshold accuracy goal is reached, the optical shape of the patch lens is stored as part of block 124. If the threshold accuracy goal is not reached, the position and / or optical shape of the patch lens is refined in block 121. The new optical shape of the patch lens is communicated (e.g., communicated to phase modulator 14) in block 122, and method 115 returns to block 117 where new data for image 93 produced with the new patch lens is captured by camera 94. Loop 123 repeats until the desired threshold accuracy is reached.

[0288] When processing the images of the image 93, the position and optical properties of the camera 94 may be taken into account. The camera 94 may for example: · May be mounted at a known position relative to the projection device; · The screen onto which the image 93 is projected may be observed through the projection lens used to project the image 93; It may be part of another device, such as a mobile phone, in data communication with the system described herein.

[0289] In some embodiments, light source 12 may include emitters that emit polychromatic light (e.g., red, green, and blue). In such embodiments, each patch lens 15A may be configured based on the wavelength of the corresponding incident beam 13. This allows a single phase modulator 14 to be used to direct light beams having different wavelengths. Typically, the arrangement of light emitting elements in light source 12 is known or can be characterized, allowing individual patch lenses 15A to be generated at specific wavelengths.

[0290] 14 illustrates a schematic of an exemplary optical arrangement 130 including a multi-emitter light source 12 having light-emitting elements that generate light of different wavelengths (e.g., red, green, and blue). Optical arrangement 130 is similar to optical arrangement 50, except that multi-emitter light source 12 includes light-emitting elements of multiple wavelengths. In such an embodiment, phase modulator 14 displays patch lens 15A that is wavelength-specific, so that light emitted by light source 12 can be directed as desired using a single phase modulator 14 (as opposed to having to use multiple wavelength-specific phase modulators 14, for example).

[0291] In some embodiments (see, e.g., FIG. 14), each of a plurality of different wavelengths of unguided light (e.g., unguided red light, unguided green light, and unguided blue light) is directed to a homogenizing input of combining rod 44. In such embodiments, combining rod 44 homogenizes the unguided light of different wavelengths in both directions of light, mixes the unguided light of different wavelengths (or colors) of light together (e.g., mixes red, green, and blue light into white light), and combines the guided light with the homogenized, color-mixed unguided light. This may advantageously reduce the number of downstream optical elements required (e.g., eliminating the need for color-combining optical elements).

[0292] The unguided light (and the guided light of a different wavelength) may be directed to the input of a coupling rod 44, as described elsewhere herein. The coupling rod 44 may be any of the coupling rods described elsewhere herein.

[0293] In some embodiments, one or more alternative light sources of different wavelengths (e.g., red, green and / or blue light sources) may be positioned to emit light into the coupling rod 44 to increase the intensity of the unguided light 17.

[0294] The multiple wavelength light emitting elements of the multi-emitter light source 12 may be arranged in any manner. In some embodiments, the multiple light emitting elements are arranged randomly. In some embodiments, the light emitting elements are arranged in rows or columns based on wavelength (e.g., a row or column of red emitters, a row or column of green emitters, and a row or column of blue emitters).

[0295] FIG. 15 is a block diagram illustrating an exemplary control system 150 of a type that may be provided in an apparatus as described herein.

[0296] The controller 25 is configured to control the light source 12 and the phase modulator 14. As described elsewhere herein, the controller 25 may receive input from the camera 94. In some embodiments, the phase modulator 14 provides feedback to the controller 25.

[0297] The controller 25 may receive user input from a user interface 151. The controller 25 may also provide information to a user via the interface 151 regarding the devices described herein.

[0298] Data regarding each patch lens displayed by phase modulator 14 may be stored in data store 152. Data store 152 may include, for example, one data entry for each optical shape corresponding to a patch lens displayed by phase modulator 14 (e.g., data entries 152A-1, 152A-2, ..., 152A-N).

[0299] In some embodiments, data store 152 includes initial patch data 153. Initial patch data 153 may include, for example, the initial optical shape of the patch lens as displayed by phase modulator 14, before the patch lens is optimized using any of the methods described elsewhere herein.

[0300] The apparatus described herein and the calibration routines executed by controller 25 may be stored in program storage 154. For example, program storage 154 may have a complete calibration routine 154A that includes machine executable instructions that are executed by controller 25 and configured to calibrate a new apparatus at the time of manufacture. Additionally or alternatively, program storage 154 may have a start-up calibration routine 154B that includes machine executable instructions that are executed by controller 25 and configured to calibrate an apparatus described herein when the apparatus is powered on (e.g., to calibrate any drift that may have occurred between multiple power-on cycles).

[0301] The systems and methods described herein are not limited to use in a single type of projector system. In some cases, the systems and methods described herein are incorporated into professional commercial cinema systems for use in movie theaters. In some cases, the systems and methods described herein are incorporated into consumer projection systems, for example for home use. [Interpretation of terms]

[0302] Unless the context clearly requires otherwise, throughout this specification and claims: · "Provides", "comprises" and the like are to be construed in an inclusive sense, i.e. "including but not limited to," as opposed to an exclusive or exhaustive sense; "Connected", "coupled" or any variation thereof means any connection or coupling between two or more elements, whether direct or indirect, and the coupling or connection between such elements may be physical, logical, or a combination thereof; · The words "herein," "above," "below," and words of similar import, when used to describe this specification, shall refer to this specification as a whole and not to any particular portions of this specification; · When referring to a list of two or more items, "or" includes all of the following interpretations of this word: any of the items in that list, all of the items in that list, and any and all combinations of the items in that list; The singular forms "one", "an" and "the" include all appropriate plural references.

[0303] Directional terms, such as "vertical," "transverse," "horizontal," "upper," "lower," "forward," "rearward," "inward," "outward," "left," "right," "front," "rear," "top," "bottom," "down," "above," and "below," when used in this specification and any appended claims, are dependent upon the particular orientation of the device as described and illustrated. The subject matter described herein may assume a variety of alternative orientations. Thus, these directional terms are not precisely defined and should not be narrowly interpreted.

[0304] Embodiments of the present invention (e.g., control systems, calibration systems, etc.) may be implemented using specifically designed hardware, configurable hardware, programmable data processors configured by providing software executable on a data processor (which may optionally include "firmware"), application specific computers or data processors specifically programmed, configured, or constructed to perform one or more steps in the methods detailed herein, and / or combinations of two or more of these. Examples of specifically designed hardware include logic circuits, application specific integrated circuits ("ASICs"), large scale integrated circuits ("LSIs"), very large scale integrated circuits ("VLSIs"), etc. Examples of configurable hardware include one or more programmable logic devices, such as programmable array logic ("PALs"), programmable logic arrays ("PLAs"), and field programmable gate arrays ("FPGAs"). Examples of configurable hardware include one or more programmable logic devices, such as programmable array logic ("PALs"), programmable logic arrays ("PLAs"), and field programmable gate arrays ("FPGAs"). Examples of programmable data processors include microprocessors, digital signal processors ("DSPs"), embedded processors, graphics processors, math co-processors, general purpose computers, server computers, cloud computers, mainframe computers, computer workstations, etc. For example, one or more data processors in control circuitry for a device may implement the methods described herein by executing software instructions in program memory accessible to the processors.

[0305] Processing may be centralized or distributed. When processing is distributed, information, including software and / or data, may remain centralized or may be distributed. Such information may be exchanged among several different functional units over a communications network, such as a local area network (LAN), a wide area network (WAN), or the Internet, wired or wireless data links, electromagnetic signals, or other data communications channels.

[0306] For example, although processes or blocks are presented in a given order, alternatives may perform routines having steps in a different order, or employ systems having blocks, or some processes or blocks may be removed, moved, added, subdivided, combined, and / or modified to provide alternative or sub-combinations. Each of these processes or blocks may be implemented in a variety of different ways. Also, while multiple processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times.

[0307] In addition, while elements are at times shown as being performed sequentially, they may instead be performed simultaneously or in different orders, and it is therefore intended that the following claims be interpreted to include all such variations as falling within their intended scope.

[0308] Where a component (e.g., a phase modulator, a light source, a coupling rod, etc.) is referred to above, unless indicated otherwise, the reference to that component (including the reference to "means") should be interpreted as including any component that performs the function of the described component (i.e., is functionally equivalent) as an equivalent of that component, including components that are not structurally equivalent to the disclosed structures that perform that function in the illustrated exemplary embodiments of the present invention.

[0309] For illustrative purposes, specific examples of systems, methods, and devices are described herein. These are merely examples. The techniques provided herein may be applied to multiple systems other than the exemplary systems described above. Many changes, modifications, additions, omissions, and permutations are possible within the practice of the invention. The invention includes variations of the described embodiments that will be apparent to those skilled in the art. These include variations obtained by replacing features, elements, and / or operations with equivalent features, elements, and / or operations, mixing and matching features, elements, and / or operations from different embodiments, combining features, elements, and / or operations from the embodiments as described herein with features, elements, and / or operations of other technologies, and / or omitting or combining features, elements, and / or operations from the described embodiments.

[0310] Various features are described herein as being present in "some embodiments." Such features are not required and may not be present in all embodiments. An embodiment of the invention may include none of such features, any one of such features, or any combination of two or more of such features. This is limited only to the extent that a particular one of such features is incompatible with other features of such features, in the sense that it would be impossible for one of ordinary skill in the art to construct a practical embodiment combining such incompatible features. As a result, a statement that "some embodiments" have feature A and "some embodiments" have feature B should be interpreted as an explicit indication that the inventors also contemplate an embodiment combining features A and B (unless otherwise stated or features A and B are fundamentally incompatible).

[0311] Accordingly, it is intended that the following appended claims and any claims hereafter introduced be interpreted as including all such modifications, permutations, additions, omissions, and subcombinations that are reasonably contemplated. The scope of the claims should not be limited by the preferred embodiments described in the examples, but should be accorded the broadest interpretation consistent with the description as a whole.

Claims

1. one or more light sources operable to emit a plurality of light beams; a phase modulator having a two-dimensional array of pixels, the pixels being controllable to retard the phase of light incident on the pixels by a variable amount, the phase modulator having an active area in an optical path of the plurality of light beams, each of the plurality of light beams being incident on the active area of ​​the phase modulator in a corresponding one of a plurality of distinct regions of the active area of ​​the phase modulator; and a controller configured to set the pixels of each of the plurality of distinct regions of the phase modulator to represent an optical shape of a patch lens corresponding to the distinct region, the patch lens configured to correct for a non-uniformity present in a corresponding one of the plurality of light beams; A projection system comprising:

2. the plurality of distinct regions are arranged in an array having a plurality of rows and a plurality of columns; The projection system of claim 1 .

3. The light source has a multi-emitter light source including at least two rows and two columns of light emitting elements.

3. The projection system of claim 1 or 2.

4. the controller is configured to configure the pixels of each of the plurality of distinct regions of the phase modulator to display a light induced phase pattern in combination with the optical shape of the corresponding patch lens.

4. The projection system of claim 1.

5. the optical shape of the patch lens corresponding to the distinct region is based, at least in part, on a measured deviation of the corresponding light beam from ideal; 5. The projection system of claim 1 .

6. the optical shape of the patch lens corresponding to the distinct region is based, at least in part, on a measured deviation from ideal of a light field produced at an image plane after the corresponding light beam interacts with the phase modulator.

6. A projection system according to any one of the preceding claims.

7. The corrected non-uniformity includes at least one of pointing parallelism, collimation, and intensity distribution.

7. The projection system of claim 1.

8. The represented optical shape corresponds to the optical shape of a spherical lens.

8. The projection system of claim 1 .

9. Adjacent patch lenses abut each other.

9. The projection system of claim 1 .

10. the entire active area of ​​the two-dimensional array of pixels of the phase modulator is covered by a patch lens; 10. The projection system of claim 1 .

11. The optical shape of each patch lens is generated independently.

11. The projection system of claim 1 .

12. the optical shape of each patch lens is generated by the controller configured to perform an optimization process.

12. The projection system of claim 1 .

13. the optimization process includes iteratively varying a phase shift of the pixel of the corresponding patch lens until one or more observed characteristics of the corresponding output beam indicate that the patch lens is adequately correcting deviations of the light beam from ideal.

13. The projection system of claim 12.

14. The optimization process is performed sequentially on different ones of the plurality of patch lenses.

14. The projection system of claim 12 or 13.

15. The optimization process is performed in parallel for different ones of the plurality of patch lenses.

14. The projection system of claim 12 or 13.

16. the optimization process includes performing a simulated annealing method to find phase displacements of the pixels within the region that will construct the phase pattern of the corresponding patch lens; 16. The projection system of any one of claims 12 to 15.

17. the optical shape of each of the plurality of patch lenses specifies at least one of a focal length, an optical center shift, a parameterized astigmatism, and a tilt of the corresponding patch lens; 17. The projection system of claim 1 .

18. at least one of the plurality of distinct regions is divided into a plurality of sub-regions, and the controller is configured to configure the pixels of each of the plurality of sub-regions to display an optical shape corresponding to the sub-region.

18. The projection system of claim 1 .

19. Different portions of a single light beam illuminate two or more sub-areas of corresponding separate areas of the phase modulator.

19. The projection system of any one of claims 1 to 18.

20. At least one of the plurality of optical shapes corresponds to a plurality of lenses superimposed on one another.

20. The projection system of claim 1 .

21. At least one of the plurality of light beams extends beyond the plurality of distinct regions.

21. The projection system of any one of claims 1 to 20.

22. one or more of the plurality of optical shapes are each changed in real time to take into account changing characteristics of a corresponding one of the plurality of light beams.

22. The projection system of any one of claims 1 to 21.

23. the optical geometry applied to each of the plurality of light beams further comprising a light guiding component for guiding light; 23. The projection system of any one of claims 1 to 22.

24. the corresponding patch lens and the corresponding light directing component are superimposed; 24. The projection system of claim 23.

25. the light guiding components applied to different ones of the plurality of light beams are the same.

25. The projection system of claim 23 or 24.

26. The light guiding components applied to different light beams are different; 26. The projection system of claim 24 or 25.

27. the light directing component is configured to direct the light beam to converge at a plurality of different points; 27. The projection system of any one of claims 23 to 26.

28. the controller individually controls each of the plurality of distinct regions of the phase modulator to display a pattern of phase shift directing light from a corresponding one of the light beams.

28. The projection system of any one of claims 23 to 27.

29. a receiving optical system upstream of the phase modulator, the receiving optical system being configured to shape or modify the light beam to better illuminate the phase modulator; 29. The projection system of any one of claims 1 to 28.

30. the receiving optics shapes the light from the light beam so that the light matches a size of a pixel in the two-dimensional array.

30. The projection system of claim 29.

31. the controller is configured to configure at least a portion of the pixels of the phase modulator to display a selected phase pattern to cause specular reflection of at least a portion of the light beams.

31. The projection system of any one of claims 1 to 30.

32. the controller is configured to dynamically vary a number of pixels in the portion of the plurality of pixels to adjust a ratio of unguided light to guided light.

32. The projection system of claim 31.

33. the controller is configured to determine a desired ratio of undirected light to directed light based at least in part on processing the image data.

33. The projection system of claim 32.

34. The controller is configured to determine a desired ratio of undirected light to directed light based at least in part on one or more of a black level of the image data, a maximum brightness of highlights in the image data, and a contrast of the image data.

34. The projection system of claim 33.

35. and a coupling rod downstream of the phase modulator, the coupling rod having entrance and exit apertures and light reflecting portions on either side of a central longitudinal axis of the coupling rod, the coupling rod being configured to combine guided and unguided light and to homogenize the unguided light by repeated reflections at the light reflecting portions before it reaches the exit aperture.

35. The projection system of any one of claims 1 to 34.

36. The connecting rod comprises a hollow tube.

36. The projection system of claim 35.

37. The connecting rod has a solid body of a permeable material.

36. The projection system of claim 35.

38. the connecting rod comprises a hollow rectangular tube including at least one tapered surface; 36. The projection system of claim 35.

39. the coupling rod has two flat reflective surfaces tapering from the entrance opening to the exit opening, the entrance opening being larger than the exit opening; 36. The projection system of claim 35.

40. the connecting rod is tapered in one plane; 36. The projection system of claim 35.

41. the connecting rod is tapered along a transverse axis of the connecting rod; 41. The projection system of claim 40.

42. the connecting rod is tapered along a vertical axis of the connecting rod; 41. The projection system of claim 40.

43. the exit angle of the light from the exit aperture is about 45° or less; 43. The projection system of any one of claims 35 to 42.

44. the coupling rod is configured to provide a substantially symmetric output; 44. The projection system of any one of claims 35 to 43.

45. a prism optically coupled to the coupling rod proximate the entrance opening, the prism configured to collect the unguided light and transmit the unguided light into the coupling rod.

45. The projection system of any one of claims 35 to 44.

46. an optical element that transmits the guided and unguided light from the phase modulator to the coupling rod; 46. ​​The projection system of any one of claims 35 to 45.

47. the optical element includes a physical lens located between the phase modulator and the coupling rod; 47. The projection system of claim 46.

48. the physical lens is positioned in a position that maximizes guided and unguided light incidence on the physical lens; 48. The projection system of claim 47.

49. a diffuser in the optical path of the unguided light upstream of the coupling rod.

49. The projection system of any one of claims 35 to 48.

50. further comprising a diffuser downstream of the connecting rod.

50. The projection system of any one of claims 35 to 49.

51. and an optical system configured to generate a base illumination to increase the intensity of the guided or unguided light.

51. The projection system of any one of claims 35 to 50.

52. and one or more additional light sources configured to generate a base illumination to augment an intensity of the guided or unguided light.

51. The projection system of any one of claims 35 to 50.

53. a camera configured to capture images of the light-induced imagery and connected to provide the captured images to the controller; 53. The projection system of any one of claims 1 to 52.

54. the controller is configured to process the captured images of the light induced imagery to determine characteristics of the light used to generate the light induced imagery and to vary one or more optical shapes of the patch lenses displayed by the phase modulator.

54. The projection system of claim 53.

55. the one or more light sources have emitters that emit polychromatic light; 55. The projection system of any one of claims 1 to 54.

56. the optical shape of each of the plurality of patch lenses is configured based at least in part on a wavelength of the corresponding light beam.

56. The projection system of claim 55.

57. the one or more light sources have emitters that emit polychromatic light, and the coupling rod homogenizes unguided light of different wavelengths in one or both of the light direction and the light color; 53. The projection system of any one of claims 35 to 52.

58. the optical shape of each of the plurality of patch lenses is configured based at least in part on a wavelength of the corresponding light beam.

58. The projection system of claim 57.

59. and further comprising one or more additional light sources of different wavelengths positioned to emit light into the coupling rod to increase the intensity of the unguided light.

59. The projection system of claim 57 or 58.

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