Abstract: A material including a glass or vitroceramic substrate having a first layer and a second layer deposited thereon, each of the first and second layers including at least one transparent conducting oxide (TCO). The first layer has a roughness of more than 1 nm and the second layer has a roughness less than or equal to 1 nm. A transmittance in the visible wavelength range of the material is at least 80%. The work function of the second layer is greater than the work function of the first layer and is greater than 4.6 eV.

Abstract: A rear projection screen for use with a projection lens which has an exit pupil (23) is provided. The screen has a light entering side and a light exiting side and comprises in order from said light entering side to said light exiting side: (a) a Fresnel structure (11); (b) a lenslet array (13); and (c) an opaque layer (15) comprising a plurality of pinholes, said pinholes being at locations which correspond to the images of the exit pupil formed by the combination of the Fresnel structure and the lenslet array.

Abstract: A light emitting diode of the stacked-layer structure type, incorporating at least one layer made of an inorganic material between the layer forming the substrate and a layer forming the light emitting layer, is provided, in which a periodic structure at the wavelength range emitted by the light emitting layer is printed.

Abstract: A light emitting diode of the stacked-layer structure type, incorporating at least one layer made of an inorganic material between the layer forming the substrate and a layer forming the light emitting layer, is provided, in which a periodic structure at the wavelength range emitted by the light emitting layer is printed.

Abstract: In a first aspect, the present invention provides a silicon thin film transistor which comprises:

Abstract: A material for in the fabrication of a luminous display device is described.

Abstract: A holographic device, which has first and second roughly coplanar and superposed holograms, which are illuminated by the same non-polarized light beam with at least first and second spectral compositions, the holograms each being recorded in a manner such that in its middle, the axis of the diffracted beam is perpendicular to the direction of the incident beam in this medium, the diffracted beams forming first and second angularly separated light beam with the same polarization, and having different spectral compositions.

Abstract: A fiber splicing apparatus of the present invention includes a support (120a, 120b) for supporting the two optical fibers (112a,112b) such that the ends (114a, 114b) thereof are aligned and in physical contact, and a laser (130) emitting a laser beam (142) onto the ends of the optical fibers to heat and thereby fuse together the ends (114a, 114b ) of the fibers (112a, 112b). According to another embodiment, an apparatus is provided for heating a region (115) of one or more optical fibers(112a, 112b). This apparatus includes a laser (130) emitting a laser beam (132) and an optical modulator (134) positioned to receive and selectively modulate the intensity of the laser beam (132) to project a modulated laser beam (138) along a first optical path that terminates at the end (114a, 114b ) of the optical fiber(s) (112a, 112b)to be heated.

Abstract: The present invention provides an N×M non-blocking optical switch using a novel switching fabric that utilizes micromirrors to switch light signals in a planar waveguide array. The optical switch uses a commercially available micromechanical actuator to actuate each micromirror. The actuator can also be an inexpensive custom made actuator. The actuator and the waveguide substrate are separate units and there are no electrical connections between them. The switch includes a unique design feature whereby the actuator and the micromirror array do not require precision alignment. The optical switch of the present invention is fabricated at low temperatures and assembled using glue.

Abstract: 1A fiber splicing apparatus of the present invention includes a support (120a, 120b) for supporting the two optical fibers (112a,112b) such that the ends (114a, 114b) thereof are aligned and in physical contact, and a laser (130) emitting a laser beam (142) onto the ends of the optical fibers to heat and thereby fuse together the ends (114a, 114b ) of the fibers (112a, 112b). According to another embodiment, an apparatus is provided for heating a region (115) of one or more optical fibers(112a, 112b). This apparatus includes a laser (130) emitting a laser beam (132) and an optical modulator (134) positioned to receive and selectively modulate the intensity of the laser beam (132) to project a modulated laser beam (138) along a first optical path that terminates at the end (114a, 114b ) of the optical fiber(s) (112a, 112b)to be heated.

Abstract: The device includes a) flat mirror (7) formed by adjacent areas (5i, 6i) that are alternately transparent and reflecting with parallel and straight lines of demarcation, b) identical first (4) and second (4′) reflection holograms, each delivering at least one diffracted beam with a predetermined spectral composition, c) illuminating source (1) for illuminating said holograms (4, 4′) at normal incidence by the intermediary of said mirror (7), said holograms (4, 4′) being arranged symmetrically with respect to the plane of said mirror (7) in such a way as to be illuminated by the intermediary of transparent (6i) and reflecting (5i) strips, respectively, of mirror (7), and in such a way that the beams diffracted by the first and second holograms are reflected and transmitted, respectively, by reflecting (5i) and transparent (6i) strips, respectively, of mirror (7), in order to be combined into a continuous light beam with said spectral composition.

Abstract: Device for elimination of the zero order beam emerging from holograms illuminated in polarized light includes a birefringent plate (5) illuminated by both said zero order beam (3) and by a diffracted beam (4) emerging from the hologram (2). The plate is arranged and sized such that one of the beams (3, 4) emerges from the plate with its plane of polarization not appreciably rotated and such that the other of said beams emerges with its plane of polarization rotated by 90°. The device further includes a polarizer (9) illuminated by the beams (3′, 4′) emergent from the birefringent plate (5), the polarizer having its plane of maximum transmittance parallel to the plane of polarization of the diffracted beam emerging from the birefringent plate as beam (4′). The device finds industrial applicability in the optical systems of video image projectors employing active matrix liquid crystal cells.

Abstract: An optical method and apparatus is disclosed for stabilizing the frequency f semiconductor lasers. The basic system includes only the optical elements of a conventional semiconductor laser optically coupled to a separate, external resonator having an optical cavity with a particular resonance frequency. The optical geometry is configured such that the output from the resonator is fed back to the laser only when the laser frequency matches or substantially matches the resonance frequency. In other disclosed embodiments, optical electronic feedback loops are used to modulate the laser injection current to stabilize the frequency and to adjust the phase of the optical feedback signal.