Illumination optics for projector systems

Abstract

Illumination optics for projector systems with high f-number light output. A projection system includes: an optical fiber input providing a first light; and a first illumination optical device configured to change the first light to the second light. The projection system includes a Fourier lens assembly configured to receive the second light and form a Fourier transform of the second light at an exit pupil of the Fourier lens assembly. The f number of the second light is between f / 10 and f / 30, the brightness uniformity of the second light is between 75% and 90% of the center, and the contrast of the second light exceeds 10000: 1.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 340,707, filed on May 11, 2022, the entire contents of which are incorporated herein by reference. background 1. Technical Field

[0004] The present application relates generally to projection systems and, more particularly, to illumination optics for laser-based image projection systems. 2. Background technology

[0005] Digital projection systems typically utilize a light source and an optical system to project an image onto a surface or screen. The optical system includes components such as mirrors, lenses, waveguides, optical fibers, beam splitters, diffusers, spatial light modulators (SLMs), phase light modulators (PLMs), and the like. Some optical systems include an illumination optical assembly or a re-imaging optical assembly to redirect and condition the light provided from the light source as it travels to the SLM or PLM. Typically, the light projected from the illumination optical assembly has a low (e.g., fast) f-number. Summary of the invention

[0006] The illumination optical assembly described herein achieves light with a high f-number (e.g., a slow f-number) before being projected onto or otherwise provided to a modulation device. In conventional digital projection systems, increasing the f-number of the light results in reduced uniformity. However, the illumination optical assembly described herein maintains high uniformity while achieving high f-number light. This increase in f-number results in a narrow illumination angle, thereby assisting in operations performed on the light downstream of the modulation device, such as spatial filtering.

[0007] Various aspects of the present disclosure relate to devices, systems, and methods for projection display.

[0008] In an exemplary aspect of the present disclosure, a projection system is provided, the projection system comprising: an optical fiber input providing a first light; and a first illumination optical device configured to change the first light into a second light. The projection system includes a Fourier lens assembly configured to receive the second light and form a Fourier transform of the second light at an exit pupil of the Fourier lens assembly. The f-number of the second light is between f / 10 and f / 30. The brightness uniformity of the second light is between 75% and 90% at the center. The contrast of the second light exceeds 10000:1.

[0009] In another exemplary aspect of the present disclosure, a method for a projection system is provided. The method includes: providing a first light with a fiber optic input; and changing the first light into a second light with a first projection optical device. The method includes: receiving the second light with a Fourier lens assembly; and forming a Fourier transform of the second light at an exit pupil of the Fourier lens assembly with the Fourier lens assembly. The f-number of the second light is between f / 10 and f / 30. The brightness uniformity of the second light is between 75% and 90% of the center. The contrast of the second light exceeds 10,000:1.

[0010] In another exemplary aspect of the present disclosure, a non-transitory computer readable medium storing instructions is provided, which when executed by a processor of a projection system causes the projection system to perform operations including: providing a first light with an optical fiber input; changing the first light into a second light with a first projection optical device; receiving the second light with a Fourier lens assembly; and forming a Fourier transform of the second light at an exit pupil of the Fourier lens assembly with the Fourier lens assembly. The f-number of the second light is between f / 10 and f / 30. The brightness uniformity of the second light is between 75% and 90% at the center. The contrast of the second light exceeds 10,000:1.

[0011] In this way, various aspects of the present disclosure provide for the display of images with high dynamic range and high resolution, and provide effective improvements in at least the technical fields of image projection, holography, signal processing, and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] These and other more detailed and specific features of various embodiments are more fully disclosed in the following description with reference to the accompanying drawings, in which:

[0013] Figure 1 illustrates a block diagram of an exemplary image projector display system according to various aspects of the present disclosure;

[0014] Figure 2 illustrates an optical configuration of an exemplary projector system according to various aspects of the present disclosure;

[0015] Figure 3A illustrates a plan view of an exemplary spatial light modulator for use with various aspects of the present disclosure;

[0016] Figure 3B The diagram shows Figure 2 A cross-sectional view taken along line II-B;

[0017] Figure 4 illustrates a plan view of an exemplary phase light modulator for use with various aspects of the present disclosure;

[0018] Figure 5illustrates a cross-sectional view of another exemplary phase light modulator for use with various aspects of the present disclosure; and

[0019] Figure 6 Exemplary projection lenses according to various aspects of the present disclosure are illustrated.

[0020] Figure 7 Illustrated are cross-sectional views of exemplary optical fibers according to various aspects of the present disclosure.

[0021] Figure 8 Exemplary lighting assemblies according to various aspects of the present disclosure are illustrated.

[0022] Fig. 9 Another exemplary lighting assembly according to various aspects of the present disclosure is illustrated.

[0023] Fig. 10A Illustrated are vertical cross-sections of exemplary emission optics assemblies according to various aspects of the present disclosure.

[0024] Fig. 10B The present invention illustrates various aspects of the present disclosure. Fig. 10A Horizontal cross section of the emission optical components.

[0025] Fig.11 Exemplary relay optical assemblies according to various aspects of the present disclosure are illustrated.

[0026] Fig.12 Another exemplary relay optical assembly according to various aspects of the present disclosure is illustrated.

[0027] Fig.13 Another exemplary lighting assembly according to various aspects of the present disclosure is illustrated.

[0028] Fig.14 Another exemplary launch optics assembly according to various aspects of the present disclosure is illustrated. DETAILED DESCRIPTION

[0029] The present disclosure and its various aspects may be implemented in various forms, including: hardware, devices or circuits controlled by computer-implemented methods, computer program products, computer systems and networks, user interfaces and application programming interfaces; as well as hardware-implemented methods, signal processing circuits, memory arrays, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), etc. The foregoing summary is intended only to give a general idea of ​​the various aspects of the present disclosure and is not intended to limit the scope of the present disclosure in any way.

[0030] In the following description, many details such as optical device configuration, timing, operation, etc. are set forth to provide an understanding of one or more aspects of the present disclosure. It is obvious to those skilled in the art that these specific details are only exemplary and are not intended to limit the scope of the present application.

[0031] In addition, although the present disclosure focuses on examples of using various circuits in digital projection systems, it should be understood that this is only one example of an implementation. It should be further understood that the disclosed systems and methods can be used in any device that requires projected light; for example, theater projection systems, consumer-grade projection systems and other commercial projection systems, head-up displays, virtual reality displays, etc.

[0032] Projector System

[0033] Figure 1 A possible embodiment of a suitable image projector display system is illustrated. In the illustrated embodiment, the projector display system is constructed as a dual / multi-modulator projection system 100. Projection system 100 uses a light source 102, which supplies the desired illumination to the projector system so that the final projected image will be bright enough for the intended viewer of the projected image. The light source 102 can include any suitable light source, such as but not limited to a xenon lamp, a laser, a coherent light source, and a partially coherent light source. In addition, the optical system described herein can implement optical fiber to transmit the light from the light source 102 to the optical device in the optical system. Although the light source and the optical fiber can be mentioned separately, it should be understood that the optical fiber is a component of the light source. Therefore, the mention of the light source alone does not exclude the optical fiber.

[0034] Light 104 from the light source 102 may illuminate a first modulator 106, which in turn may illuminate a second modulator 110 via an optional set of optical components 108. Light from the second modulator 110 may be projected by a projection lens 112 (or other suitable optical components) to form a final projected image on a screen 114. The first modulator 106 and the second modulator 110 may be controlled by a controller 116. The controller 116 may receive input image and / or video data, and may perform certain image processing algorithms, gamut mapping algorithms, or other such suitable processing on the input image / video data, and output control / data signals to the first modulator 106 and the second modulator 110 to achieve a desired final projected image on the screen 114. Additionally, in some projector systems, the light source 102 may be modulated (control lines not shown) depending on the light source to achieve additional control over the image quality of the final projected image.

[0035] The light recycling module 103 Figure 1, which is depicted as a dashed box in FIG. 1 , the light recycling module can be placed in the light path from the light source 102 to the first modulator 106. It should be understood that the light recycling can be inserted into the projector system at various points in the projector system. For example, the light recycling can be placed between the first modulator and the second modulator. In addition, the light recycling can be placed at more than one point in the light path of the display system.

[0036] Although Figure 1 The embodiments are presented in the context of dual modulation, multi-modulation projection systems, but it should be understood that the techniques and methods of the present application will be applicable to single modulation or other dual modulation, multi-modulation display systems. For example, a dual modulation display system including a backlight, a first modulator (e.g., LCD, etc.) and a second modulator (e.g., LCD, etc.) can use appropriate optical components and image processing methods and techniques to affect the performance and efficiency discussed herein in the context of a projection system. It should also be understood that even if Figure 1 While a two-stage or dual modulator display system is depicted, the methods and techniques of the present application may also be applied to display systems having only one modulator or display systems having three or more modulators (multi-modulator) display systems. The scope of the present application encompasses these various alternative embodiments.

[0037] Figure 2 Another example projection system 200 is illustrated. The projection system 200 includes an illumination assembly 204 (e.g., illumination optics) that receives light from a fiber optic input 202 and feeds the light into a modulation assembly 206. The modulation assembly 206 includes a prism 208 and a modulator 210 (e.g., a reflector device). The modulator 210 can be configured as a digital light processing (DLP) device, as described in more detail below.

[0038] In some examples, the light from the fiber input 202 is a white light input, and the prism 208 is a white light prism. In such examples, the prism 208 includes several prism parts. For example, a spectral filter such as a yellow notch filter can be provided in the prism 208. Additional parts can be used as a TIR prism. In some embodiments, the modulation component 206 includes three modulators 210 (e.g., 3 chips) for modulating the received white light. The prism 208 splits the white light into several color beams (e.g., three color channels), one color beam for each modulator 210. A controller (such as the controller 116) can be coupled to each modulator 210 to control the modulation of each color beam. The modulator 210 then modulates its corresponding color beam, and then the modulated color beams are combined in the prism 208. In other embodiments, the modulator 210 directly modulates the white light. In both embodiments, the modulation component 206 then relays the output beam to the projection optics 214 of the projection system 200. In some embodiments, the projection optics 214 is included in the projection lens. In other embodiments, a portion or section of projection optics 214 is included in a projection lens.

[0039] In other examples, the projection system 200 includes several fiber optic inputs 202 from several color channels, such as a red channel, a blue channel, and a green channel. In such examples, the illumination assembly 204 shown receiving the fiber optic inputs 202 corresponds only to the monochromatic channels provided for the prism 208. Several illumination assemblies 204 can be included to direct light from the fiber optic inputs to the prism 208. In such examples, the prism 208 is a color light prism that receives each fiber optic input 202 and redirects each color channel to a corresponding modulator 210. After modulation, the modulated color channels are combined and directed toward the projection optics 214.

[0040] Exemplary modulation device

[0041] Modulator 210 (and in some embodiments, Figure 1 The first modulator 106 and the second modulator 110 in FIG. 2 can be configured as a DLP device. In some embodiments, the modulator 210 is a digital micromirror device (DMD) composed of multiple mirrors for adjusting the incident angle of light. To illustrate the impact of the incident angle and the DMD mirrors, FIG. 3A to FIG. 3B An exemplary DMD 300 is illustrated in accordance with various aspects of the present disclosure. In particular, Figure 3A FIG. 1 shows a plan view of DMD 300. Figure 3B The diagram shows Figure 3A1B is a partial cross-sectional view of a DMD 300 taken along line IB illustrated in FIG. DMD 300 includes a plurality of square micromirrors 302 arranged in a two-dimensional rectangular array on a substrate 304. Each micromirror 302 may correspond to a pixel of a final projected image, and may be configured to tilt around a rotation axis 308 (which is shown for a specific subset of micromirrors 302) due to electrostatic or other types of actuation. Each micromirror 302 has a width 312 and is arranged to be spaced apart by gaps having a width 310. Micromirrors 302 may be formed of or coated with any highly reflective material such as aluminum or silver, thereby specularly reflecting light. The gaps between micromirrors 302 may be absorptive, so that input light entering the gaps is absorbed by substrate 304.

[0042] Although Figure 3A Only some representative micromirrors 302 are explicitly shown, but in practice the DMD 300 may include a greater number of individual micromirrors equal to the resolution of the projection system 200. In some examples, the resolution may be 2K (2048×1080), 4K (4096×2160), 1080p (1920×1080), consumer 4K (3840×2160), etc. Furthermore, in some examples, the micromirrors 302 may be rectangular and arranged in a rectangular array; may be hexagonal and arranged in a hexagonal array, etc. Furthermore, although Figure 3A The rotation axis 308 is illustrated extending in an oblique direction, but in some embodiments, the rotation axis 308 may extend vertically or horizontally.

[0043] like Figure 3B As can be seen in FIG. 1 , each micromirror 302 may be connected to a substrate 304 via a yoke 314 that is rotatably connected to the micromirror 302. The substrate 304 includes a plurality of electrodes 316. Figure 3B Only two electrodes 316 are visible per micromirror 302 in the cross-sectional view of FIG. 3 , but each micromirror 302 may actually include additional electrodes. Figure 3B As specifically shown in FIG. 3 , DMD 300 may further include a spacer layer, a support layer, a hinge component for controlling the height or orientation of micromirror 302, etc. Substrate 304 may include electronic circuits associated with DMD 300, such as complementary metal oxide semiconductor (CMOS) transistors, memory elements, etc.

[0044] Depending on the specific operation and control of the electrode 316, each micromirror 302 can be switched between an "on" position, an "off" position, and an unactuated or neutral position. If the micromirror 302 is in the on position, it is actuated to an angle of, for example, -12° (i.e., 12° counterclockwise relative to the neutral position) to mirror-reflect the input light 306 into an on-state light 318. If the micromirror 302 is in the off position, it is actuated to an angle of, for example, +12° (i.e., 12° clockwise relative to the neutral position) to mirror-reflect the input light 306 into an off-state light 320. The off-state light 320 can be directed toward a light collector that absorbs the off-state light 320. In some instances, the micromirror 302 can be unactuated and parallel to the substrate 304. In FIG. 3A to FIG. 3B The specific angles illustrated in and described herein are exemplary only and are not limiting. In some embodiments, the open position angle and the closed position angle may be between ±11 degrees and ±13 degrees, respectively (inclusive). In other embodiments, the open position angle and the closed position angle may be between ±10 degrees and ±18 degrees, respectively (inclusive).

[0045] In some embodiments, the modulator 210 is a phase light modulator (PLM) configured to impart a spatially varying phase modulation to light. The PLM can be a reflective type, where the PLM reflects incident light with a spatially varying phase; alternatively, the PLM can be a transmissive type, where the PLM imparts a spatially varying phase to the light as the light passes through the PLM. In some aspects of the present disclosure, the PLM has a liquid crystal on silicon (LCOS) architecture. In other aspects of the present disclosure, the PLM has a microelectromechanical system (MEMS) architecture.

[0046] Figure 4 An example of a modulator 210 is illustrated, which is implemented as a reflective LCOS PLM 400 and is shown in a partial cross-sectional view. Figure 4As shown, the PLM 400 includes a silicon backplane 410, a first electrode layer 420, a second electrode layer 430, a liquid crystal layer 440, a cover glass 450, and a spacer 460. The silicon backplane 410 includes electronic circuits associated with the PLM 400, such as CMOS transistors, etc. The first electrode layer 420 includes an array of reflective elements 421 disposed in a transparent matrix 422. The reflective elements 421 can be formed of any highly optically reflective material such as aluminum or silver. The transparent matrix 422 can be formed of any highly optically transmissive material such as a transparent oxide. The second electrode layer 430 can be formed of any optically transparent conductive material such as an indium tin oxide (ITO) film. The second electrode layer 430 can be provided as a common electrode corresponding to the plurality of reflective elements 421 of the first electrode layer 420. In such a configuration, each of the plurality of reflective elements 421 will be coupled to the second electrode layer 430 via a corresponding electric field, thereby dividing the PLM 400 into an array of pixel elements. Therefore, each reflective element (or a subset) of the plurality of reflective elements 321 may be addressed via electronic circuitry disposed in the silicon backplate 410 , thereby modifying the state of the corresponding reflective element 421 .

[0047] The liquid crystal layer 440 is disposed between the first electrode layer 420 and the second electrode layer 430, and includes a plurality of liquid crystals 441. The liquid crystals 441 are particles that exist in a phase between a solid state and a liquid state; in other words, the liquid crystals 441 exhibit a certain degree of directional order, rather than positional order. The direction in which the liquid crystals 441 tend to point is called a "director." The liquid crystal layer 440 modifies the incident light entering from the cover glass 450 based on the birefringence Δn of the liquid crystals 441, which can be expressed as the difference between the refractive index in a direction parallel to the director and the refractive index in a direction perpendicular to the director. Thus, the maximum optical path difference can be expressed as the birefringence multiplied by the thickness of the liquid crystal layer 440. The thickness is set by a spacer 460, which seals the PLM 400 and ensures that the cover glass 450 is separated from the silicon backplane 410 by a set distance. The liquid crystals 441 generally orient themselves along the electric field lines between the first electrode layer 420 and the second electrode layer 430. As Figure 4 As shown, liquid crystal near the center of PLM 400 is oriented in this manner, while liquid crystal 441 near the periphery of PLM 400 is substantially unoriented due to the absence of electric field lines passing therethrough. By addressing each of the plurality of reflective elements 421 via a phase drive signal, the orientation of liquid crystal 441 can be determined on a pixel-by-pixel basis.

[0048] Figure 5 Another example of a modulator 210 is illustrated, which is implemented as a DMD PLM 500 and is shown in a partial cross-sectional view. Figure 5As shown, the PLM 500 includes a back plate 510 and a plurality of controllable reflective elements as pixel elements, each of which includes a yoke 521, a reflective mirror plate 522, and a pair of electrodes 530. Figure 5 Only two electrodes 530 are visible in the cross-sectional view of FIG, but each reflective element may actually include additional electrodes. Figure 5 As particularly shown in FIG. 5 , PLM 500 may further include a spacer layer, a support layer, a hinge component for controlling the height or orientation of the reflector plate 522, etc. Backplane 510 includes electronic circuits associated with PLM 500, such as CMOS transistors, a memory array, etc.

[0049] The yoke 521 may be formed of or include a conductive material to allow a bias voltage to be applied to the mirror plate 522. The mirror plate 522 may be formed of any highly reflective material such as aluminum or silver. The electrodes 530 are configured to receive a first voltage and a second voltage, respectively, and may be individually addressable. Depending on the value of the voltage on the electrode 530 and the voltage on the mirror plate 522 (e.g., the bias voltage), there is a potential difference between the mirror plate 522 and the electrode 530, which generates an electrostatic force acting on the mirror plate 522. The yoke 521 is configured to allow the mirror plate 522 to move vertically in response to the electrostatic force. The equilibrium position of the mirror plate 522 that occurs when the electrostatic force and the spring-like force of the yoke 521 are equal determines the optical path length of the light reflected from the upper surface of the mirror plate 522. Therefore, each of the controllable reflective elements in the plurality of controllable reflective elements is controlled to provide a plurality of (three as shown) discrete heights and thus provide a plurality of discrete phase configurations or phase states. As illustrated, each phase state has a flat curve. In some aspects of the disclosure, electrodes 530 may be provided with different voltages from one another in order to impart a tilt to mirror plate 522. Such a tilt may be used with light collectors of the type described above.

[0050] The PLM 500 may be capable of a high switching speed, such that the PLM 500 switches from one phase state in, for example, the order of tens of μs. To provide a complete phase control cycle, the total optical path difference between the state where the mirror plate 522 is at its highest point and the state where the mirror plate 522 is at its lowest point should be approximately equal to the wavelength λ of the incident light. Therefore, the height range between the highest point and the lowest point should be approximately equal to λ / 2.

[0051] In some embodiments, the PLM 500 creates fixed diffraction orders where the mirror plate 522 produces multiple "copies" of light impinging thereon. The PLM 500 steers the light within the range of each diffraction order, thereby producing multiple "copies" of the image on the reconstruction plane. The image steered by the PLM 500 can be formed at a distance on the image reconstruction plane where the diffraction orders are separated and do not overlap. In some embodiments, the image reconstruction plane is closer to the PLM 500 to reduce blurring of the reconstructed image. A Fourier filter is implemented with the PLM 500 to remove overlap of the diffraction orders at the image reconstruction plane. In some embodiments, the diffraction patterns constructively interfere with each other to form the reconstructed image. Therefore, if a portion of the light steered by the PLM 500 is blocked, the reconstructed image is blurred compared to a reconstructed image that includes all of the light from the PLM 500.

[0052] Example Projection Lens System

[0053] As previously described, the modulated light from the modulation assembly is directed toward projection optics 214. In some implementations, projection optics 214 are provided within a projection lens architecture. Figure 6 6 is an exploded view of an exemplary projection lens system 600 according to various aspects of the present disclosure. The projection lens system 600 has a modular design. The projection lens system 600 includes a Fourier portion 601 (e.g., a Fourier lens assembly), an aperture 602, and a zoom portion 603 (also referred to as a zoom lens assembly), the Fourier portion being configured to form a Fourier transform of an object at an exit pupil. The spatial Fourier transform applied by the Fourier portion 601 converts the propagation angle of each diffraction order of the modulated light into a corresponding spatial position on a Fourier plane. The Fourier portion 601 is thereby able to select the desired diffraction order and reject the undesired diffraction order by performing spatial filtering at the Fourier plane. The spatial Fourier transform of the modulated light at the Fourier plane is equivalent to the Fraunhofer diffraction pattern of the modulated light.

[0054] The Fourier portion 601 includes a first attachment section 604, which may include threads, fasteners, etc. The zoom portion 603 includes a second attachment section 605, which may include complementary threads, fasteners, etc. to allow mating with the first attachment section 604. In one example, the first attachment section 604 includes a portion with external threads and the second attachment section 605 includes a portion with internal threads, or vice versa. In another example, the first attachment section 604 and the second attachment section 605 are configured for friction fit, in which case one or more fastening elements such as screws, cams, flanges, etc. may be provided. In yet another example, the first attachment section 604 may include one or more radial pins and the second attachment section 605 may include a corresponding number of L-shaped slots, or vice versa, so as to connect the Fourier portion 601 with the zoom portion 603 using a bayonet connection. By these examples, the Fourier portion 601 can be removably attached to the zoom portion 603 to provide a modular assembly.

[0055] Although Figure 6 The Fourier portion 601 and the zoom portion 603 are illustrated as being completely separable, but the present disclosure is not limited thereto. In some embodiments, the Fourier portion 601 and the zoom portion 603 are only partially separable, for example by providing an access portion in one of the Fourier portion 601 and the zoom portion 603. The access portion may be a slot, a door, a window, etc., through which an operator can access and / or replace the aperture 602. In such an embodiment, the Fourier portion 601 and the zoom portion 603 may be bonded (e.g., via an adhesive on the first attachment segment 604 and / or the second attachment segment 605) to prevent complete separation. Alternatively, the Fourier portion 601 and the zoom portion 603 may be provided with an integral housing including an attachment portion.

[0056] The aperture 602 is configured to block a portion of the light (eg, modulated light corresponding to one or more diffraction orders) in the projection lens system 600 (eg, modulated light provided via the modulation component 206). Figure 6 As illustrated, aperture 602 is a square opening having sides having a length of, for example, 6 mm. Figure 6 Also illustrated is an optical axis 610 of projection lens system 600. When assembled, Fourier portion 601 and zoom portion 603 are substantially coaxial with each other and with optical axis 610. In some embodiments (e.g., depending on the illumination angle), aperture 602 is further substantially coaxial with optical axis 610.

[0057] Projection lens system 600 can include or be associated with one or more non-optical elements, including heat dissipation devices such as heat sinks (or cooling fins), one or more adhesives (or fasteners), etc. In some embodiments, aperture 602 can block and thus absorb approximately 15% of incident light, and thus the heat sink or cooling fins can be positioned and configured to appropriately dissipate heat from aperture 602. In some embodiments, aperture 602 is thermally isolated from other portions of projection lens system 600.

[0058] The Fourier portion 601 and the aperture 602 operate together as a Fourier lens with a spatial filter, which can also be used as a fixed projection projection lens. Figure 6 The zoom portion 603 illustrated in the figure can be one of a series of zoom lens assemblies configured to be attached to the Fourier portion 601, thereby producing a series of projection zoom lens systems and adapting to different theaters. In other words, the Fourier portion 601 and the aperture 602 can be adapted to any theater setting, while the zoom portion 603 provides a specific projection light pattern customized for a specific theater. Therefore, by selecting a specific zoom portion 603 from a series of zoom lens assemblies and attaching the selected zoom portion 603 to the Fourier portion 601 and the aperture 602, a projection lens system 600 adapted to a specific theater can be achieved. In addition, both the Fourier portion 601 and the zoom portion 3503 can include multiple individual lens elements.

[0059] Example Fiber Optic Input

[0060] Figure 7 An example optical fiber 700 for use with a light source (such as light source 102) is provided. The optical fiber 700 includes an outer cladding 705 and a plurality of inner fibers 710. The inner fibers 710 collectively form an output light projected by the optical fiber 700. In some embodiments, the plurality of inner fibers 710 collectively form a circular light output provided to the illumination optical device 204. In other embodiments, a subset of the inner fibers 710 is used to form a rectangular optical fiber output as shown by a rectangular portion 715. The rectangular portion 715 can have an aspect ratio that matches a downstream modulator (such as the first modulator 106 and / or the second modulator 110). In some embodiments, the optical fiber 700 has an aspect ratio of a 16 by 9 array of inner fibers 710. In some embodiments, the optical fiber 700 is composed of 10 to 200 individual fibers (e.g., inner fibers 710). In some embodiments, each inner fiber 710 has a diameter of approximately (e.g., ±50) 450 microns and has a numerical aperture (NA) of approximately 0.22.

[0061] Exemplary Lighting Assemblies

[0062] In optical configurations, the f-number (expressed as f / #) is the ratio of the focal length of the system to the diameter of the aperture. As f / # increases, uniformity of light may be lost, thereby creating additional artifacts in the projected image. The illumination assembly described herein achieves a high f-number with a narrow illumination angle while maintaining uniformity of light impinging on a modulating device.

[0063] Figure 8 An illumination assembly 800 is provided as one possible embodiment of an illumination assembly 204. A laser fiber source 802 illuminates a set of optical elements 804 (e.g., a collimator) that provide a substantially collimated light source. Thereafter, the substantially collimated light may illuminate an optical homogenizing element (e.g., a fly's eye lens arrangement) 806. The fly's eye lens arrangement may be arranged directly after the set of optical elements 804 that provide a substantially collimated light source. The fly's eye lens arrangement tends to provide a suitable illumination angular distribution in combination with an optical power sufficient to substantially focus the light onto an integrator rod 808. The fly's eye lens arrangement may be arranged directly before the integrator rod 808, i.e., may be arranged directly adjacent to the integrator rod 808 along an optical path passing through the illumination assembly 800. Thereafter, light from the integrator rod 808 may illuminate a downstream optical element 810 that may provide additional optical power that may be a desired cross-sectional illumination (as depicted by an imaginary plane 812). Thereafter, this illumination may illuminate a modulator 814. Additional details regarding the fly's eye lens arrangement may be found in U.S. Patent No. 10,281,730, "Optical System For Image Projectors," which is incorporated herein by reference in its entirety.

[0064] Fig. 9An illumination assembly 900 is provided as another possible embodiment of an illumination assembly 204. A laser source 902 (e.g., fiber input 202) illuminates (e.g., provides light to) an emission optical device 905 (shown in more detail in FIG. 10). The emission optical device 905 (e.g., re-imaging optical device) focuses the light onto a first integrator rod 910. From the first integrator rod 910, the light is illuminated onto a second integrator rod 915. In some instances, a diffuser 920 is placed between the first integrator rod 910 and the second integrator rod 915 to remove artifacts and improve the uniformity of light traveling through the first integrator rod 910 and the second integrator rod 915. This configuration fills the entrance of the second integrator rod 915, thereby maximizing the integration capability of the illumination assembly 900. The second integrator rod 915 directs the light toward the relay optical device 925. In some embodiments, the light directed by the second integrator rod 915 has a substantially rectangular shape. The relay optics 925 directs the light from the second integrator rod 915 toward the prism 930 to illuminate the prism 930. The prism 930 directs the light toward the modulation device 935 where it is modulated. The modulated light is directed toward the projection lens 940. In some embodiments, the emission optics 905 and the relay optics 925 can be combined using a single integrator rod rather than implementing two separate integrator rods. The f / # of the light directed toward the prism 930 can be in the range of f / 20 and f / 30.

[0065] FIG. 10A to FIG. 10B provides a method that can be implemented as Fig. 9 Example emission optics 1000 of emission optics 905 of the present invention. A first cylindrical lens 1002 receives light from a laser source 902. The first cylindrical lens 1002 directs the light to a second cylindrical lens 1004 (or otherwise modifies the light). The second cylindrical lens 1004 directs the light to a filter 1006 (e.g., a bandpass filter, a monochromatic bandpass filter). The first cylindrical lens 1002 and the second cylindrical lens 1004 are used together to collimate the light from the laser source 902. The filtered light is directed to a fly's eye lens 1008. The fly's eye lens 1008 directs the light to a plano-convex lens 1010. The plano-convex lens 1010 directs the light to a plano-concave lens 1012. The plano-concave lens 1012 directs the light to a first integrator rod 910. A diffuser 1014 may be optically disposed between the plano-concave lens 1012 and the first integrator rod 910 to smooth high frequency artifacts, improve spatial and angular uniformity of light, and create a Gaussian shape for the light distribution.

[0066] Fig.11 provides a method that can be implemented as Fig. 9100. Light from the second integrator rod 915 is illuminated by the first lens assembly 1105 onto the second lens assembly 1115 and passes through the illumination aperture stop 1110. The first lens assembly 1105 and the second lens assembly 1115 re-image the end of the second integrator rod 915 onto the downstream modulator and magnify the image coming out of the second integrator rod 915. The light at the illumination aperture stop 1110 can have an f / # of approximately f / 15. In some examples, the light at the illumination aperture stop 1110 has an f / # of approximately f / 25. The f / # of the light at the illumination aperture stop 1110 can depend on the amount of expansion of the light provided by the laser source 902. The second lens assembly 1115 illuminates the light onto the prism 930, where the light is split into separate color channels and modulated at the modulation device 935. The light at the modulation device 935 can have an f / # of approximately f / 30.

[0067] Fig.12 provides a method that can be implemented as Fig. 9 Another example of relay optics 925 of relay optics 1200. Light from second integrator rod 915 is directed by first lens assembly 1205 toward second lens assembly 1215 and through illumination aperture stop 1210. Second lens assembly 1215 illuminates light onto prism 930 where it is split into separate color channels and modulated at modulation device 935.

[0068] Although the example transmit optics 1000 and the example relay optics 1100, 1200 use a particular lens configuration, other lens configurations may be implemented to implement the desired f / #, such as concave lenses, convex lenses, bi-concave lenses, bi-convex lenses, plano-concave lenses, plano-convex lenses, negative meniscus lenses, and positive meniscus lenses.

[0069] Fig.13Another illumination assembly 1300 is provided as a possible embodiment of the illumination assembly 204. A laser source 1302 (e.g., a fiber optic input 202) illuminates (e.g., provides light to) an emission optic. The emission optic 1305 focuses the light onto an integrator rod 1310. The integrator rod 1310 directs the light toward a relay optic 1315. The light directed by the integrator rod 1310 can have a rectangular shape. The relay optic 1315 illuminates (or directs) the light from the integrator rod 1310 onto a prism 1320. The prism 1320 directs the light toward a modulator 1325, where the light is modulated. The f / # of the light impinging on the prism 1320 can be in the range of f / 10 and f / 20. In some embodiments, the f / # of the light impinging on the prism 1320 is 12.5 at an illumination aperture stop included in the relay optic 1315. In some examples, example relay optics 1100 or relay optics 1200 are implemented as relay optics 1315 within lighting assembly 1300 .

[0070] Lighting assembly 1300 can be used with high etendue light sources. Etendue is a measure of emitting area multiplied by solid angle and is expressed in mm 2 *sr(steradian), M 2 More specifically, the amount of extension can be given as: π*area*NA 2 Therefore, the light projected by a single fiber optical input has a higher power than that projected by a cluster of fiber optical inputs (e.g. Figure 7 The light projected by the plurality of inner fibers 710) has a low etendue. A high etendue light source may have, for example, 0.2 mm 2 *sr to 50mm 2 *sr expansion. A single fiber with a diameter of about 450 microns disclosed herein may have an expansion of about 0.024 mm 2 *sr expansion. A fiber with a diameter of about 100 microns may have an expansion of about 0.0012 mm 2 *The expansion amount of sr.

[0071] Fig.14 provides a method that can be implemented as Fig.13 14. Example emission optics 1400 of emission optics 1305 of FIG. 14. Plano-convex lens 1402 receives light from laser source 1302 and directs the light onto first plano-convex lens 1404. First ECX lens 1404 receives light and directs the light onto second plano-convex lens 1406. Second ECX lens 1406 receives light and directs the light onto integrator rod 1310. In some embodiments, emission optics 1400 amplifies light from laser source 1302 as it is directed onto integrator rod 1310.

[0072] Uniformity and efficiency analysis

[0073] The example of the illumination assembly 204 achieves a high f / # implementation while maintaining high uniformity (e.g., macroscopic uniformity, spot uniformity from modal noise, and speckle uniformity of fine-grained light spots) on the projected image. The brightness uniformity of the projected image is expressed as a percentage of the brightness values ​​at the sides and corners of the image relative to the value at the center of the image. The brightness uniformity of the image projected by the projection system 200 can be, for example, between 75% and 90% at the center, between 80% and 90% at the center, and between 85% and 90% at the center.

[0074] Additionally, chromaticity uniformity is measured at the corners of the projected image and is calculated separately for each location as the x or y value at that location minus the x or y value at the center of the image. The example of illumination assembly 204 achieves chromaticity uniformity within a range from ±0.000x, ±0.000y at the center to ±0.015x, ±0.015y at the center.

[0075] Thus, examples of illumination assembly 204 described herein achieve slow f / #s (f / # greater than f / 10) that aid in filtering undesired diffraction orders at the Fourier filter. Additionally, examples of illumination assembly 204 described herein achieve slow f / # values ​​while maintaining high efficiency and high uniformity of the projected image. The image contrast achieved by examples of illumination assembly 204 may range from 10,000:1 to 20,000:1, 20,000:1 to 30,000:1, 30,000:1 to 40,000:1, or greater than 40,000:1.

[0076] Systems, methods, and devices according to the present disclosure may adopt any one or more of the following configurations.

[0077] (1) A projection system comprising: a fiber optic input providing a first light; a first illumination optical device configured to change the first light into a second light; and a Fourier lens assembly configured to receive the second light and form a Fourier transform of the second light at an exit pupil of the Fourier lens assembly, wherein the second light has an f-number between f / 10 and f / 30, wherein the second light has a brightness uniformity between 75% and 90% at a center, and wherein the second light has a contrast ratio exceeding 10,000:1.

[0078] (2) The projection system according to (1), wherein the first illumination optical device includes: a first integrator rod; a second integrator rod; and a diffuser, the diffuser being located between the first integrator rod and the second integrator rod.

[0079] (3) The projection system of (2), wherein the first illumination optical device includes: a collimating lens that substantially collimates the first light from the fiber input onto the first integrator rod.

[0080] (4) The projection system according to any one of (2) to (3), further comprising: a relay optical component, wherein the relay optical component is configured to receive the second light from the first illumination optical device and redirect the second light into third light, wherein the relay optical device includes an aperture stop, and wherein the f-number of the second light passing through the aperture stop is approximately f / 12.

[0081] (5) The projection system according to any one of (1) to (4), further comprising: a prism configured to receive the second light from the illumination optical device and redirect the second light into a third light; and a modulation device configured to receive the third light and modulate the third light into a fourth light, wherein the Fourier lens assembly is configured to receive the fourth light and form a Fourier transform of the fourth light at an exit pupil of the Fourier lens assembly to generate a filtered light output.

[0082] (6) The projection system according to (5), wherein an f-number of the third light received by the modulation device is approximately f / 30.

[0083] (7) The projection system of any one of (5) to (6), wherein the Fourier lens assembly is integrated into a projection lens assembly, and the projection lens assembly is configured to project the filtered light output.

[0084] (8) The projection system according to any one of (1) to (7), wherein an f-number of the second light is between f / 10 and f / 20.

[0085] (9) The projection system according to any one of (1) to (7), wherein an f-number of the second light is between f / 20 and f / 30.

[0086] (10) The projection system according to any one of (1) to (9), wherein the fiber input is a bundle of optical fibers arranged in a rectangular array.

[0087] (11) A method for a projection system, the method comprising: providing a first light using a fiber optic input; changing the first light into a second light using a first illumination optical device; receiving the second light using a Fourier lens assembly; and forming a Fourier transform of the second light at an exit pupil of the Fourier lens assembly using the Fourier lens assembly, wherein the f-number of the second light is between f / 10 and f / 30, wherein the brightness uniformity of the second light is between 75% and 90% at the center, and wherein the contrast of the second light exceeds 10,000:1.

[0088] (12) The method for a projection system according to (11), wherein the first illumination optical device includes: a first integrator rod; a second integrator rod; and a diffuser, wherein the diffuser is located between the first integrator rod and the second integrator rod.

[0089] (13) The method for a projection system according to (12), further comprising: collimating the first light input from the optical fiber onto the first integrator rod using a collimating lens.

[0090] (14) The method for a projection system according to any one of (12) to (13), further comprising: receiving the second light from the first illumination optical device using a relay optical component, and redirecting the second light into third light using the relay optical component, wherein the relay optical component includes an aperture stop, and wherein the f-number of the second light passing through the aperture stop is approximately f / 12.

[0091] (15) The method for a projection system according to any one of (11) to (14) further includes: receiving the second light from the first illumination optical device using a prism, redirecting the second light into a third light using the prism, receiving the third light using a modulation device, modulating the third light into a fourth light using the modulation device, receiving the fourth light using the Fourier lens assembly, and forming a Fourier transform of the fourth light at an exit pupil of the Fourier lens assembly using the Fourier lens assembly to produce a filtered light output.

[0092] (16) The method for a projection system according to (15), wherein an f-number of the third light received by the modulation device is approximately f / 30.

[0093] (17) A method for a projection system according to any one of (15) to (16), wherein the Fourier lens assembly is integrated into a projection lens assembly, and wherein the method further comprises: projecting the filtered light output using the projection lens assembly.

[0094] (18) The method for a projection system according to any one of (11) to (17), wherein an f-number of the second light is between f / 10 and f / 20.

[0095] (19) The method for a projection system according to any one of (11) to (17), wherein an f-number of the second light is between f / 20 and f / 30.

[0096] (20) A non-transitory computer-readable medium storing instructions that, when executed by a processor of a projection system, cause the projection system to perform operations including the method according to any one of (11) to (19).

[0097] With respect to the processes, systems, methods, heuristics, etc. described herein, it should be understood that although the steps of these processes, etc. have been described as being performed in a particular ordered order, these processes can be practiced with the described steps performed in an order different from that described herein. It should further be understood that certain steps can be performed simultaneously, other steps can be added, or certain steps described herein can be omitted. In other words, the process descriptions herein are provided for the purpose of illustrating certain embodiments and should in no way be construed as limiting the claims.

[0098] Therefore, it should be understood that the above description is intended to be illustrative and not restrictive. By reading the above description, many embodiments and applications other than the examples provided will be apparent. The scope should not be determined with reference to the above description, but should be determined with reference to the full range of equivalents to which the appended claims and these claims are eligible to be considered. It is expected and hoped that the technology discussed herein will develop in the future, and the disclosed systems and methods will be incorporated into such future embodiments. In a word, it should be understood that the present application is capable of modification and change.

[0099] All terms used in the claims are intended to be given their broadest reasonable interpretations and ordinary meanings as understood by those skilled in the art described herein, unless an explicit indication to the contrary appears herein. In particular, use of singular articles such as "a," "the," "said," etc. should be understood to recite one or more of the indicated elements, unless a claim recites an explicit limitation to the contrary.

[0100] The abstract of the present disclosure is provided to allow the reader to quickly determine the nature of the technical disclosure. This abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the aforementioned detailed description, it can be seen that various features are combined together into various embodiments for the purpose of connecting the present disclosure as a whole. The method of the present disclosure should not be interpreted as reflecting the intention that the claimed embodiments incorporate more features than those explicitly recited in each claim. On the contrary, as reflected in the attached claims, the inventive subject matter lies in less than all the features of a single disclosed embodiment. Therefore, the attached claims are hereby incorporated into the detailed description, and each claim stands alone as a separately claimed subject matter.

Claims

1. A projection system, comprising: An optical fiber input, wherein the optical fiber input provides a first light; first illumination optics configured to change the first light into second light; as well as a Fourier lens assembly configured to receive the second light and form a Fourier transform of the second light at an exit pupil of the Fourier lens assembly, wherein the f-number of the second light is between f / 10 and f / 30, wherein the brightness uniformity of the second light is between 75% and 90% at the center, and wherein the contrast of the second light exceeds 10000:

1.

2. The projection system of claim 1, wherein: The first illumination optics comprises: First scoring stick; A second integrating rod; and A diffuser is located between the first integrator rod and the second integrator rod.

3. The projection system of claim 2, wherein: The first illumination optics comprises: A collimating lens is provided to substantially collimate the first light from the optical fiber input onto the first integrator rod.

4. The projection system of claim 2, further comprising: a relay optics assembly configured to receive the second light from the first illumination optics and redirect the second light into third light, Wherein the relay optical assembly comprises an aperture stop, and wherein the f-number of the second light passing through the aperture stop is approximately f / 12.

5. The projection system of claim 1, further comprising: a prism configured to receive the second light from the first illumination optics and redirect the second light into third light; as well as a modulation device configured to receive the third light and modulate the third light into a fourth light, Wherein, the Fourier lens assembly is configured to receive the fourth light and form a Fourier transform of the fourth light at an exit pupil of the Fourier lens assembly to generate a filtered light output.

6. The projection system of claim 5, wherein: The f-number of the third light received by the modulation device is approximately f / 30.

7. The projection system of claim 5, wherein: The Fourier lens assembly is integrated within a projection lens assembly configured to project the filtered light output.

8. The projection system of claim 1, wherein: The f-number of the second light is between f / 10 and f / 20.

9. The projection system of claim 1, wherein: The f-number of the second light is between f / 20 and f / 30.

10. The projection system of claim 1, wherein: The fiber optic input is a bundle of optical fibers configured as a rectangular array.

11. A method for a projection system, the method comprising: A first light is provided by using an optical fiber input, changing the first light into a second light using a first illumination optical device, receiving the second light using a Fourier lens assembly, and forming a Fourier transform of the second light at an exit pupil of the Fourier lens assembly using the Fourier lens assembly, wherein the f-number of the second light is between f / 10 and f / 30, wherein the brightness uniformity of the second light is between 75% and 90% at the center, and wherein the contrast of the second light exceeds 10000:

1.

12. The method for a projection system according to claim 11, wherein: The first illumination optics comprises: First scoring stick; A second integrating rod; and A diffuser is located between the first integrator rod and the second integrator rod.

13. The method for a projection system as claimed in claim 12, further comprising: The first light input from the optical fiber is collimated onto the first integrator rod by using a collimating lens.

14. The method for a projection system according to claim 12, further comprising: receiving the second light from the first illumination optics with a relay optical assembly, and redirecting the second light into third light using the relay optical component, Wherein the relay optical assembly comprises an aperture stop, and wherein the f-number of the second light passing through the aperture stop is approximately f / 12.

15. The method for a projection system according to claim 11, further comprising: receiving the second light from the first illumination optical device using a prism, redirecting the second light into third light using the prism, receiving the third light by a modulation device, modulating the third light into a fourth light using the modulation device, receiving the fourth light using the Fourier lens assembly, and A Fourier transform of the fourth light is formed at an exit pupil of the Fourier lens assembly using the Fourier lens assembly to produce a filtered light output.

16. The method for a projection system according to claim 15, wherein: The f-number of the third light received by the modulation device is approximately f / 30.

17. The method for a projection system according to claim 15, wherein: The Fourier lens assembly is integrated into a projection lens assembly, and wherein the method further comprises: The filtered light output is projected using the projection lens assembly.

18. The method for a projection system according to claim 11, wherein: The f-number of the second light is between f / 10 and f / 20.

19. The method for a projection system according to claim 11, wherein: The f-number of the second light is between f / 20 and f / 30.

20. A non-transitory computer readable medium storing instructions that, when executed by a processor of a projection system, cause the projection system to perform operations including the method of claim 11.

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