Abstract: A liquid crystal display device (10) includes a front polarizer (12), a liquid crystal cell (14), a retardation film (16), a back polarizer (18), and a reflective holographic optical element (20). Diffuse ambient light illuminates the front polarizer (12), which polarizes the ambient light and transmits the polarized light to the liquid crystal cell (14). The liquid crystal cell (14) receives the polarized light and transmits polarized light derived from the incident polarized light to the retardation film (16). The retardation film (16) receives the polarized light and transmits polarized light, including light within a selected spectral band. The back polarizer (18) receives the polarized light from the retardation film (16) and selectively transmits polarized light derived from the incident polarized light.

Abstract: A liquid crystal display device (10) for forming a display includes a liquid crystal panel (12), a switchable holographic optical element (14), and a reflective holographic optical element (16). Ambient light illuminates a front polarizer (18), which polarizes the ambient light and transmits the polarized light to the liquid crystal cell (20). The liquid crystal cell (20) receives the polarized light and transmits polarized light derived from the incident polarized light to a back polarizer (22). The back polarizer (22) polarizes the light and transmits the light to the switchable holographic optical element (14). While in a first mode, the switchable holographic optical element (14) redirects the light back toward the liquid crystal panel (12) within a first viewing cone (34) to form the display. In a second mode, the switchable holographic optical element (14) is transparent and transmits the light to the reflective holographic optical element (16).

Abstract: A microelectronic assembly (10) includes an integrated circuit die (12) mounted onto a substrate (14) and spaced apart by a gap (30). Solder bump interconnections (32) extend across the gap (30) and physically attach and electrically connect an electrical circuit on the substrate (14) to an electrical circuit on the integrated circuit die (12). The gap (30) is filled with a transparent encapsulant (16) to protect the solder bump interconnections (32). The transparent encapsulant (16) is composed of a polymeric matrix and filler particles dispersed in the matrix. The polymeric matrix and the filler particles have substantially similar indices of refraction, thereby making the encapsulant (16) transparent. The integrated circuit die (12) includes light emitting diodes (18) that transmit light toward the transparent substrate (14) to form a display.

Abstract: A liquid crystal display device (30) that is illuminatable by diffuse ambient light comprises a liquid crystal panel (32) and a reflective holographic optical element (34). Diffuse ambient light illuminating the front side (36) of the liquid crystal panel and traversing the liquid crystal panel is received at a reflection site (66) and is redirected with a reflection pattern (68) to retraverse the liquid crystal panel to form a bright pixel for a display. By concentrating diffuse light within a preferential reflection pattern, the reflective holographic optical element provides enhanced brightness for viewing the display under ambient light conditions. In one aspect, the reflective holographic optical element is a transflector (158, 208) and is combined with an internal light source (170, 220) for illuminating the display using either reflected ambient light or backlighting.

Abstract: A display device comprises a polymer dispersed liquid crystal film that includes one or more translucent regions and one or more transparent regions. The back side of the polymer dispersed liquid crystal film is illuminated by collimated light. The front side of the polymer dispersed liquid crystal film is optically coupled to an asymmetric optical diffuser. The asymmetric optical diffuser comprises a plurality of light paths that transmit collimated light emanating through a transparent region of the film, but excludes diffuse light emanating from a translucent region. A preferred asymmetric optical diffuser comprises glass microspheres in a black matrix. In this manner, the asymmetric diffuser substantially improves contrast between a transparent region and a translucent region of a display.

Abstract: A display device (10) includes a display panel, such as a liquid crystal panel (12), in combination with a reflective holographic optical element (14) that redirects ambient light for illuminating the display. The light redirected by the holographic element is limited to a predetermined spectral band. Fluorescent film (16) is included for absorbing light outside the spectral band of the holographic element and re-emitting light within the spectral band to increase the light redirected by the holographic element and thus increase the apparent brightness of the display.

Abstract: A multilayer optical memory has interleaved optical recording media layers and control layers. In a transmissive system, the recording media layers are sensitive to the polarization (linear or circular) of a light beam. The control layers are polarization modulators. In a reflective system, the control layers are notch filters.

Abstract: A light diffuser (100) for illuminating a display (304) comprises a rectangular light distributor (108) which is coupled to a light director (208) located along an edge normal to a major axis (110) of the light distributor (108). The light director (208) directs light received from a lamp (14) into the light distributor (108). The light distributor (108) has a polished, planar top surface (210) and a bottom surface (112) comprising a predetermined serration pattern oriented normal to the major axis (110) of the rectangular light distributor (108). The predetermined serration pattern comprises a plurality of grooves (116, 118, 120) having a predetermined pitch gradient corresponding thereto. The plurality of grooves (116, 118, 120) further have roughened surfaces for diffusing light impinging thereon toward the polished, planar top surface (210) of the light distributor (108).