Abstract:
A substrate-guided holographic diffuser has a light-guide section configured to in-couple light and transmit the light within itself via total internal reflection. It can also have a brightness enhancement section that recycles non-diffracted light within the light-guide section. A hologram section that receives light from the light-guide section has a holographic structure defining acceptance conditions and is positioned relative to the internally reflected light such that the internally reflected light meets the acceptance conditions of the holographic structure. The internally reflected light is out-coupled by the holographic structure as a projected image of light scattered from a diffuser.
Abstract:
A collimator can be made of a compound holographic optical element made of three holographic optical elements. The first reflection holographic optical element will have recorded within it continuous lens configured to receive light from a diffuse light beam and diffract the received light as a first collimated light beam. The second reflection holographic optical element will have recorded within it a regular hologram that is configured to permit the light from the diffuse light source to transmit through it to reach the first reflection holographic element, the second reflection holographic element having within it a second holographically reflective structure configured to receive the first collimated light beam and diffract the first collimated light beam as a second collimated light beam. The third transmission holographic optical element is configured to receive the second collimated light beam and diffract it as a third holographic light beam.
Abstract:
A liquid crystal device comprises a first and second cell wall structure; at least one liquid crystal material disposed within a space between the first and second cell wall structures; and polymer micro-structures, wherein the micro-structures are formed by polymerizing a prepolymer, and wherein said micro-structures have a shape and spatial location determined by said liquid crystal material. Permanent polymer micro-structures are formed from a liquid crystal with a non-uniform spatially modulated director field. The polymer structures have the shape and spatial location dictated by the non-uniform director field of the liquid crystal. The micro-structures are a backbone that restores the liquid crystal director field that existed during the polymerization process even when other factors, such as electric field, temperature, or surface anchoring, do not favor this restoration. The polymer micro-structures can be used in optical devices, such as diffraction gratings and deflecting and beam steering devices, and in micro-mechanical and micro-fluidic devices.
Abstract:
A color display and solar cell device (100, 300, 500), and methods for fabricating and operating the device. The device (100, 300, 500) includes a transparent light source (140, 340, 540) located behind a liquid crystal display (105, 305, 505) that includes a switchable transflector layer (145, 345, 545). In a first embodiment, the liquid crystal display (105) also includes a tri-color pixelized filter (115), the switchable transflector (145) is a switchable broadband transflector, and the transparent light source (140) is a white light source. In a second embodiment, the switchable transflector layer (345) is a tri-color selectable transflector and the transparent light source (340) is a tri-color selectable light source. In a third embodiment, the switchable transflector layer is a switchable broadband transflector and the transparent light source is a tri-color selectable light source. In a fourth embodiment, the switchable transflector layer (545) is a switchable pixelized tri-color transflector and the transparent light source (540) is a tri-color selectable light source.
Abstract:
A head-up display includes an image source, such as a laser scanner, a means for diffusing light and a transparent element that can include a holographic element. The laser scanner emits a visible light for generating an image. The means for diffusing light receives the visible light from the laser scanner to project the image thereon, and preferably apply gain thereto. The transparent element produces a virtual or a real image of the image from the means for diffusing light. In a vehicle, the head-up display is configured to reflect the image into the vehicle to provide a virtual image ahead of a driver.