Abstract: A depth image capture device uses a circular polarization structure positioned at the output of an illumination radiation source, such as a diode laser. A linear polarization element receives the collimated illumination radiation and provides polarized radiation to a quarter wave plate. Radiation exits the quarter wave plate as circularly polarized radiation and is provided to a diffractive optical element outputting a pattern to illuminate a target. A detector receives a reflection of the output pattern from the target.

Abstract: Embodiments related to the enhancement of contrast in an image pattern in a structured light depth sensor are disclosed. For example, one disclosed embodiment provides, in a structured light depth sensor system comprising a structured light depth sensor, a method comprising projecting a light pattern onto an object, detecting via an image sensor an image of the light pattern as reflected from the object, increasing a contrast of the light pattern relative to ambient light present in the image of the light pattern as reflected from the object to form a contrast-enhanced image of the light pattern as reflected from the object, and based upon a motion of the object as detected via the contrast-enhanced image of the light pattern, controlling an application that is providing output to a display.

Abstract: A dual-mode includes a light source configured to project a structured illumination from which visible light can be filtered. The dual-mode imager also includes a detector configured to capture both the structured illumination and visible light from the scene. A temporal or spatial filter is used to selectively block visible light from one or more portions of the detector while passing the structured illumination to the one or more portions of the detector.

Abstract: A depth-sensitive imager for imaging a scene in three dimensions. The depth-sensitive imager comprises a light source configured to project a polarized illumination onto a surface of the scene, and a detector configured to capture an image of the scene by detecting light from the scene, in which image a polarization state of the light is encoded. The detected light includes a portion of the polarized illumination reflected from the surface. The depth-sensitive imager further comprises an analyzer configured to generate output responsive to a distance between the light source and the surface based on the image.

Abstract: Embodiments related to the enhancement of contrast in an image pattern in a structured light depth sensor are disclosed. For example, one disclosed embodiment provides, in a structured light depth sensor system comprising a structured light depth sensor, a method comprising projecting a light pattern onto an object, detecting via an image sensor an image of the light pattern as reflected from the object, increasing a contrast of the light pattern relative to ambient light present in the image of the light pattern as reflected from the object to form a contrast-enhanced image of the light pattern as reflected from the object, and based upon a motion of the object as detected via the contrast-enhanced image of the light pattern, controlling an application that is providing output to a display.

Abstract: Embodiments are disclosed herein related to the construction of optical elements for structured light depth sensor systems. One disclosed embodiment provides a depth sensing system with an optical component comprising a first substrate surface, a first optical element formed in a polymer layer disposed on the first substrate surface, a second substrate surface, and a second optical element formed in a polymer layer disposed on the second substrate surface, wherein the second optical element is optically aligned with the first optical element. The depth sensing further comprises a projector configured to provide light to form a pattern to illuminate a target, and a sensor to acquire an image of the pattern.

Abstract: A method and apparatus for reducing speckle in a laser illumination system uses a despeckle device including an optical retarder providing an odd integer multiple of substantially half-wave retardation for light emitted from a coherent laser in the laser illumination system. The near half-wave optical retarder has a substantially constant retardance and a spatially varied slow axis. The spatially varied slow axis imposes a phase mask on the beam of light, which provides sub-resolution optical phase modulation to a resolution spot on the detector. The near half-wave optical retarder is actuated mechanically or electrically to vary the sub-resolution optical phase modulation within an integration time of the detector.

Abstract: A micro-array of optical vortex retarders is provided by forming an alignment layer having a plurality of discrete alignment patches with different orientations. A layer of birefringent material, including one of a liquid crystal and a liquid crystal polymer precursor material, is provided adjacent to the alignment layer. The aligning orientation and position of each discrete alignment patch in the plurality of discrete alignment patches is selected to induce the layer of birefringent material to form at least one optical vortex retarder adjacent to a substantially non-oriented region of the alignment layer.

Abstract: A method and apparatus for reducing speckle in a laser illumination system uses a despeckle device including an optical retarder providing an odd integer multiple of substantially half-wave retardation for light emitted from a coherent laser in the laser illumination system. The near half-wave optical retarder has a substantially constant retardance and a spatially varied slow axis. The spatially varied slow axis imposes a phase mask on the beam of light, which provides sub-resolution optical phase modulation to a resolution spot on the detector. The near half-wave optical retarder is actuated mechanically or electrically to vary the sub-resolution optical phase modulation within an integration time of the detector.

Abstract: The invention provides a space-variant liquid-crystal (LC) photo-aligned waveplate having a vortex optic axis pattern, and an apparatus and method for fabricating thereof. The method in it preferred embodiment includes exposing a substrate coated with a photo-alignable material such as LPP to linearly polarized UV radiation through a wedge-shaped aperture, while rotating two of the aperture, the substrate and the polarization of the UV light, so that an exposure area performs a full rotation about a center point on the substrate, at angular velocities selected so as to form a vortex alignment pattern of a pre-defined order. An LC material is then deposited on the substrate in direct contact with the photo-alignable material so that the LC director is aligned according to the photo-induced vortex alignment pattern. The method enables to fabricate vortex waveplate of any pre-defined vortex order.

Abstract: The present invention relates to a passive depolarizer for use in an optical system having an image plane. The passive depolarizer includes a patterned half wave plate incorporating a monolithic layer of birefringent material. The monolithic layer includes a plurality of regions having fast axes with at least four different orientations. Accordingly, a polarized beam of light launched into the patterned half wave plate is substantially depolarized at the image plane.

Abstract: An attenuation filter contains absorbing thin film layers, which comprise gray metals or metal compounds. The attenuation filter offers significant advantages when used in optical communication systems subjected to a relatively high flux of incident light. It was surprisingly discovered that particular thin film materials provide significant protection to the attenuating thin film layer thereby improving the temporal stability and power handling capacity over prior art devices.

Abstract: This invention relates to attenuation filters having absorbing thin film layers, which comprises gray metals or metal compounds. The attenuation filters offer significant advantages when used in optical communication systems wherein they are subjected to a relatively high flux of incident light. It was surprisingly discovered that particular thin film materials provide significant protection to the attenuating thin films layer thereby improving the temporal stability and power handling capacity over prior art devices.