Abstract: An apparatus for processing optical signals includes a cladding material having therein at least two elongate core regions which serve as respective waveguides. A coupling portion therein includes adjacent and parallel portions of the two waveguides which extend sufficiently closely for a sufficient distance to permit coupling of radiation between these waveguide portions. Structure is provided that respectively permits and frustrates such coupling for respective component signals having respective different wavelengths. The coupling portion may optionally include an externally controlled switching section that can have a selected one of two states in which is respectively transmissive and nontransmissive to radiation.

Abstract: A method and apparatus for document imaging is disclosed. The apparatus uses a flatbed scanner with a selectively opaque/transparent liquid crystal platen. The platen is divided into controllable segments defined by an electrode pattern formed within the platen itself. These segments can each be selectively made transmissive or opaque by applying appropriate voltages to the segment electrodes. An advantage of the invention is that it can operate without a platen cover, since the area of the platen not covered by the original can be made opaque. The opaque part of the platen directs imaging light back into the system, shielding a user's eyes and helping to create a white background if the platen is imaged.

Abstract: A projection display system comprises a light source that generates non-polarized light having at least two polarization states and having a first color component, a second color component, and a third color component. At least one color selection device selectively transmits at different times one of the second and third color components. The system has at least four polarized light modulators, two of the light modulators each generating a respective image associated with each respective polarization state of the first color component, and two of the light modulators each generating a respective image associated with a respective polarization state of one of the second and third color components transmitted by the color selection device. The system also has a projection lens for projecting the images from the polarized light modulators. Alternative projection display systems are disclosed, together with a method for projecting color images.

Abstract: A projection display system for reflective light valves includes a light source for generating a light beam having RGB light components, wherein the red light component is p-polarized and the green and blue light components are s-polarized; a reflector structure having plural polarizing beam splitter and dichroic filters therein, wherein each PBS and DF reflects a preselected light component and transmits a different preselected light component, and a LCD panel for generating a light-component-specific image associated with each light component; and a projection lens for projecting an image combined from the light-component-specific images from the LCDs; wherein a light-component-specific image passes through one and only one PBS and through one and only one DF between the LCD and the projection lens.

Abstract: A spatial light modulator (70) comprised of an array of micromirrors (72) each having support post (74). The support post (74) defines support post edges (76) in the upper surface of the mirrors (72). These support post edges (76) are all oriented at 45 degree angles with respect to an incident beam of light from a light source (80) to minimize diffraction of light from the edges (76) into the darkfield optics when the mirrors are oriented in the off-state. The present invention achieves an increased contrast ratio of about 20% over conventional designs.

Abstract: A spatial light modulator (70) comprised of an array of micromirrors (72) each having support post (74). The support post (74) defines support post edges (76) in the upper surface of the mirrors (72). These support post edges (76) are all oriented at 45 degree angles with respect to an incident beam of light from a light source (80) to minimize diffraction of light from the edges (76) into the darkfield optics when the mirrors are oriented in the off-state. The present invention achieves an increased contrast ratio of about 20% over conventional designs.

Abstract: A full color projection system is disclosed herein. The projection system includes a means for generating a first light beam and also a means for generating a second light beam. These means may include either separate light sources 10a and 10b or a single light source 10 and a means for dividing the light source into the first and second light beams. In two examples, the means for dividing may include either a dichroic color wheel 40 or a color splitting prism 52. When a color splitting prism is used, they prisms are separated by an air gas where the distance of the air gap is determined by the size of spacer balls suspended in an adhesive between the two prisms. The first light beam will be modulated by a first spatial light modulator 30a and the second light beam will be modulated by a second spatial light modulator 30b. These spatial light modulators 30a and 30b are preferably, but not in necessarily digital micromirror devices.

Abstract: The present invention provides a method of ameliorating the effects of misalignment between modulator, and a system using the same. The individual modulator elements are positioned such that a portion of the image produced is generated by both elements. The contribution to the combined output made by each element varies across the overlapped region, with each element making a small contribution to the pixels in the overlapped region at one end and a large contribution to pixels in the overlapped region at the other end. Because the overlapping output regions of the modulators collectively form a portion of the image, any alignment error is effectively spread over the entire overlapped region and is much less noticeable.

Abstract: The present invention provides a method of ameliorating the effects of misalignment between modulator arrays, and a system using the same. The individual arrays are positioned such that a portion of the image produced by the arrays is generated by both arrays. The contribution to the combined output made by each array varies across the overlapped region, with each array making a small contribution to the pixels in the overlapped region at one end and a large contribution to pixels in the overlapped region at the other end. Because the overlapping portions of the modulator arrays collectively form a portion of the image, any alignment error is effectively spread over the entire overlapped region and is much less noticeable.

Abstract: A spatial light modulator (40,70,80,90,130) operable in the analog mode for light beam steering or scanning applications. A deflectable mirror (42, 72) and which may be hexagonal (92, 132) is supported by a torsion hinge (44,86,94) ends along a torsion axis. A plurality of flexure hinges (48,82,106) are provided to support the ends of the mirror (42,72,92,132) and provide a restoration force. The combination of the torsion hinges and the flexure hinges realizes a deflectable pixel that is operable in the linear range for a large range of address voltages. The flexure hinges also maintain a flat undeflected state when no address voltage is applied, and prevent the pixel from collapsing. The pixel may be reinforced, such as about its perimeter (74) to ensure mirror flatness and prevent warping, even during extreme deflections of the mirror. The pixel is electrostatically deflected by applying an address voltage to an underlying address electrode (60,96,98).

Abstract: A method of using a display system having a spatial light modulator (14) to display holographic images. The spatial light modulator (14) generates images that represent vertical strips of a hologram. These images are de-magnified by a three-dimensional optics unit (18), in the horizontal direction so as to form image strips. A scanning mirror (45) scans the image strips in a series across an image plane at a rate sufficiently fast that the viewer perceives a composite hologram comprised of these image strips.

Abstract: A color wheel assembly (15, 15a, 15b) for use in a display system (10) that uses a beam of source illumination to generate images with a display device. The color wheel (15) is moveable in and out of the path of the source beam so as to provide varying levels of brightness or color saturation. The color wheel (15') may also have concentric rings (41, 43) for varying saturation or color balance.

Abstract: An optical system for directing light to a spatial light modulator 16 (e.g., a digital micro-mirror device) is disclosed herein. This system can be used with displays, printers or cameras. The system includes a first light generating apparatus 30a for generating a first beam of light and a second light generating apparatus 30b for generating a second beam of light. A first lens 36a directs the first beam of light toward the spatial light modulator 16 at a first angle. Also, a second lens 36b directs the second beam toward the spatial light modulator 16 at a second angle. The system also includes an apparatus 34 which redirects either the first or the second beam of light away from the spatial light modulator 16.

Abstract: A spatial light modulator (40, 70, 80) operable in the analog mode for light beam steering or scanning applications. A deflectable mirror (42, 72) is supported by a torsion hinge (44) along a torsion axis. A plurality of flexure hinges (48) are provided to support the corners of the mirror (42, 72) and provide a restoration force. The combination of the torsion hinges and the flexure hinges realizes a deflectable pixel that is operable in the linear range for a large range of address voltages. The flexure hinges also maintain a flat undeflected state when no address voltage is applied, and prevent the pixel from collapsing. The pixel may be reinforced, such as about its perimeter (74) to ensure mirror flatness and prevent warping, even during extreme deflections of the mirror. The pixel is electrostatically deflected by applying an address voltage to an underlying address electrode (60).

Abstract: A full color projection system is disclosed herein. The projection system includes a means for generating a first light beam and also a means for generating a second light beam. These means may include either separate light sources 10a and 10b or a single light source 10 and a means for dividing the light source into the first and second light beams. In two examples, the means for dividing may include either a dichroic color wheel 40 or a color splitting prism 52. The first light beam will be modulated by a first spatial light modulator 30a and the second light beam will be modulated by a second spatial light modulator 30b. These spatial light modulators 30a and 30b are preferably, but not in necessarily digital micromirror devices.

Abstract: A method for multiple phase light modulation, said method comprising providing a pixel (20) having at least two modulating elements (22), (24). The method further comprising addressing said at least two modulating elements (22), (24) whereby light incident on said addressed element undergoes discrete phase changes between addressable states. The method further comprises resolving light from said at least two modulating elements (22), (24), into a response having at least three unique phases. Other devices, systems and methods are also disclosed.

Abstract: An optical signal processor which employs a coherent light source, two spatial light modulators and a beam splitter. Light is from the source is reflected from the beam splitter and sent to a first spatial light modulator, then sent through the beam splitter, a Fourier transform is performed and the transformed light is then reflected from the second spacial light modulator. The light form the second spacial light modulator is then inverse transformed and returned to the beam splitter where it is reflected to a readout detector. The signal read out is the correlation map between an input image from the first modulator and a filter image of the second modulator.

Abstract: A phase-contrast DMD based image system 36 for projecting an amplitude and phase modulated image. A flexure beam DMD array 34 is used to allow analog phase modulation of reflected light 38. The phase modulation is converted to amplitude modulation by the phase-contrast imaging optics including a phase plate 42. The resulting amplitude modulated wave is flicker-free and does not need to be synchronized to optical image sensors.

Abstract: An illumination control unit (17) for a projection display system (10) that uses a digital mirror device (DMD) (15) to generate images. The illumination control unit (17) has a first set of lenses (23) for receiving light from a source and focussing the light to a color filter (24). A second set of lenses (25) receives the colored light and directs it to a prism (28). The prism (28) bends the light toward the reflective mirrors (30) of the DMD (15), and a collimating lens (28a) provides a beam that is approximately the size of the mirror array of the DMD (15). An optical shutter (26) is interposed between the second set of lenses (25) and the prism (28a), and permits the system (10) to achieve a "black state" between image displays or to achieve modulated brightness levels of images being displayed.

Abstract: Techniques for achieving high resolution, high-speed gray scale printing with binary spatial light modulators. A spatial light modulator array is divided into subarrays, and the subarrays are illuminated at various levels (510, 512, 514, 516) of a modulated light source. Additionally, each pixel (520) can be divided up into four phases and printed in phase pairs.