Abstract: A filter for a display system is provided which includes a fluid chamber having a selectively moveable filtering fluid, plural electrodes being coupled with the fluid chamber to accommodate establishment of an electric field whereby the filtering fluid may be selectively positioned in an optical path.

Abstract: A light-filtering element for a display device is provided. The element includes at least one filter having a chamber with a filtering fluid, the filtering fluid selectively disposed in an optical path, and a liquid motion actuator selectively configured to move the filtering fluid substantially into and out of the optical path.

Abstract: A projector that has a narrow-spectrum light source to complement a broad-spectrum light source is disclosed. The broad-spectrum light source has a broad spectrum. The narrow-spectrum light source has a narrow spectrum complementing the broad spectrum of the broad-spectrum light source.

Abstract: The invention is a system for scanning a document. A light source illuminates the document; an imager receives light from the document and directs it toward a detector array which produces a corresponding array of electrical signals. The imager has several optical properties that are useful either individually or in combination. The imager is telecentric and thereby ensures that image size and magnification are insensitive to object displacement along the optical axis and image brightness is uniform independent of object off-axis distance. An aspheric element within the imager balances focus variation within the depth of field with spherical aberration and thereby provides nearly uniform image resolution. A diffraction pattern, carried by the imager, corrects for spectral dispersion which occurs when light passes from air into a refractive material. An imager with a reflecting surface provides a system that is subject to little or no chromatic aberration.

Abstract: Scan exposure in a row or swath scanner is controlled by pulsing light sources with pulses that are separated by dark intervals from each other--and from the detector readout periods. Detector sequencing is thereby made independent of the velocity of the pixel-line advance mechanism. Different pulse widths for different colors provide color correction without calculation, or regularize color-space conversion calculations where needed. In a swath scanner, known technology of printing modes is imported into the scanning context. Order of pixel columns within each swath is reversed for printing--permitting use of novel configurations such as a dual-parallel-flatbed copier in which a single common scan-and-advance mechanism simultaneously transports the scan sensor and printheads. To produce mirror images, this configuration is also used without column reversal. In addition to red, green and blue light sources, an infrared source is used for reading invisible indicia that identify forms or media types.

Abstract: In a liquid crystal light valve projector, a quarter-wave compensator plate is disposed between a polarization plate and a liquid crystal light valve to compensate for polarization irregularities induced by the off-incident reflections in the cone of light projected onto the LCLV. The quarter-wave compensation plate reverses the phase of the P component of said illumination light with respect to said compensator plate by 180.degree. thereby eliminating P-polarization leakage during the dark state of an LCLV projector. The invention also combines the compensator plate with a heat shield and a low stress-optical coefficient counter electrode substrate to reduce the birefringence of the LCLV thereby also minimizing leakage of P-polarized light onto the projection screen during the dark state of the projector.

Abstract: A projection system employs a reflective light valve (10) that is optically addressed by an image from a cathode ray tube (12) and provides an output image for projection by means of a high intensity reading light from a lamp (16) directed to the output face of the liquid crystal light valve. Improved reading illumination is provided by scanning the face of the liquid crystal light valve (10) with a narrow beam of light (80) that moves across the liquid crystal light valve face in synchronism with a scanning image from the writing CRT (12). The scanned narrow band of illumination is provided by refractive transmission through a rotating transparent polygonal body (50,74) having pairs of mutually parallel sides (54,56,58,60,75,76,77a,b), wherein different pairs of sides may be made to transmit light of different colors for color projection.