Abstract: An electromagnetically controlled optical switch having a plurality of optical inputs. An optical signal at each input is spatially decomposed into two coparallel, orthogonally polarized beams by a birefringent element. An array of field-controlled polarization rotators are positioned in the paths of the decomposed light beams so that the polarization of the emergent beam pairs are set to be at one of the orthogonal states (i.e., both beams are either vertical or horizontally polarized). A following birefringent element spatially routes the light beam pairs based upon their polarization. A second array of polarization rotators follows the second birefringent element and is set to be in the opposite state from the first array, such that the emergent beams are orthogonal to their input states before they entered the first polarization rotator. The beams are combined by a birefringent element to form a plurality of combined beams that are coupled to output ports.

Abstract: An arrangement for measuring desired parameters of a contact lens by optical sectioning which comprises a support fixture on which a contact lens is positioned. The support fixture includes a container in which a pedestal is positioned, and the container is filled with a saline solution. The contact lens is placed on the pedestal completely immersed in the saline solution. A line of light is generated and directed by imaging and shaping optical elements over the edge of the container and through a selected diameter of the contact lens. An imaging camera detects and image of the light scattered at the surfaces of the contact lens at the selected diameter, which is captured by a frame grabber and is digitally stored for subsequent image processing and determination of the desired parameters of the contact lens.

Abstract: A method and device for examining the internal structure of an object uses diffracted X-rays or other penetrating radiation. In one embodiment, spatial filters proximate to a source of radiation transmit an array of divergent pixel-beams which irradiate an object being examined. The object absorbs, refracts, diffracts, and incoherently scatters radiation from the pixel-beams. Spatial filters proximate to a detector block undeflected and refracted radiation which exits the object. The detector separately measures diffracted radiation for each pixel-beam. For example, an integral of the diffracted intensity around a pixel-beam provides a pixel intensity in an image of the object. Alternatively, analyzing the intensity in a diffraction pattern around a pixel-beam can identify structures and materials within the object. A non-invasive procedure identifies abnormal tissue by measuring radiation diffracted at an angle characteristic of the diffraction pattern for abnormal tissue.

Abstract: Disclosed is an ophthalmic lens inspection method and apparatus comprising a camera to capture an image of an ophthalmic lens which has been illuminated by a light source. Location and intensity at each camera pixel is converted to an electrical quantity which is then transferred and stored in a memory. A computer containing instructions for comparing the intensity and location values of the pixels starts near the center of the receptor field and continues toward the edge of the field until an intensity deviation is encountered. By evaluating the pixels containing intensity variation, an outline of the lens edge is attained. An annulus is generated enclosing the actual lens edge. All the pixels are changed from an absolute intensity value to a gradient value, represented by two transition edges. Feature extraction is performed to locate defective pixels and place them into groups.

Abstract: A method and apparatus for the manufacture of lens molds used in the formation of optical contact lenses, the apparatus including a center gate aligned on the central axis of the lens mold cavity for delivery of the melt polymer in an axisymmetrical manner. The methodology produces lens molds of extremely precise dimensions as measured against lens molds produced with side gated technology.

Abstract: Corneal onlays for use in surgical implantation into or onto the cornea of a mammal are described. The corneal onlays according to the invention have an optical axis region with optical characteristics which provide visual acuity therethrough and are comprised of a non-biodegradable non-hydrogel ocularly biocompatible material, characterized in that the onlay has a porosity sufficient to allow passage therethrough of tissue fluid components having a molecular fluid weight greater than 10,000 daltons so as to provide for a flux of tissue fluid between cells anterior of the implanted onlay and cells posterior thereof. The porosity of the optical axis region is such that it allows the flux of tissue fluid components whilst excluding ingrowth of ocular tissue. The onlay is further characterized by being adapted for epithelial recolonization.

Abstract: Concentric aspheric multifocal lens designs are disclosed which use a combination of an aspheric front surface, which results in aberration reduction and contrast vision enhancement, along with a concentric multifocal back surface, to produce a lens design which affords clear vision at a distance and also near without a loss in contrast which is generally typical of prior art simultaneous vision, concentric multifocal lens designs. The aspheric surface improves the modulation transfer function (MTF) of the lens eye combination which improves the focus and contrast of both distance and near images. The design form is valid for contact lenses and intraocular lenses.

Abstract: The present invention describes novel statistical copolymers and the preparation and possible uses thereof. Copolymers are described that are water-soluble and cross-linkable and that comprise the copolymerisation product of a monomer mixture consisting substantially of a vinyl lactam (a) and at least one further vinyl monomer (b) of a different type selected from the group consisting of hydrophobic, hydrophilic and functional vinyl monomers, wherein the monomers are present in the copolymer in the form of statistically distributed building blocks, and, if a functional vinyl monomer is present as a building block in the copolymer, that building block is, where appropriate, modified with a reactive vinyl monomer (c), the reactive vinyl monomer (c) being linked to a building block of a functional vinyl monomer with retention of its vinylic group and with the formation of a covalent bond.

Abstract: The present invention, which relates to the transfer of contact lenses in post hydration processing of the lenses. A lens transfer and insertion assembly removes contact lenses from lens hydration pallets, alters their spatial distribution, and deposits them into packaging elements. The lenses are transferred with fluid and retained on the transfer assembly by surface tension.

Abstract: Improved goggles for use with laser projection systems allow passage of a narrow band of red wavelengths that surround the wavelength at which the laser is projecting. The goggles block adjacent wavelengths. Thus, the laser image is in contrast, and is easily seen by a wearer. At the same time, the goggles pass at least a portion of the blue and green wavelengths. Thus, the wearer is provided with an image that is not unnatural, but includes most of the natural colors. In this way, the goggles not only provide a clear image of the laser beam, but also are easily worn by a wearer for an extended period of time.

Abstract: A transmitter for transmitting a plurality of digital signals through a plurality of channels, the channels having a predetermined total allocated bitrate, includes a plurality of encoders each associated with one channel, a multiplexer for receiving the encoded digital signals and for transmitting the encoded signals as a stream of data, and operable for adjusting the distribution of the bitrate allocation between and among the encoded signals, and a processing device for providing an indication of a target quality and an actual quality for each channel and for causing the multiplexer to repeatedly adjust the distribution of the bitrate allocation in response to differences between the indicated actual quality and the indicated target quality for each channel so as to equalize differences between the actual and target quality across at least some of the channels.

Abstract: A binocular head mounted display unit utilizing a single display and binocular optical system is shown for projecting an enlarged image of displayed information in the direct line of sight and central field of view of each of the user's eyes, while maintaining the user's peripheral vision free from obstruction to allow the user to selectively focus on the virtual image or not. The binocular optical system directs the user's eyes inward at an angle that is natural for a person viewing an object at a distance that is less than infinity. Further, the binocular optical system automatically compensates for variations in the interpupillary distances of various users, wherein those variations may be as great as one inch. This head mounted display unit is suitable for a variety of applications, including virtual reality applications, as well as a display for a compact portable computer.

Abstract: A naphthopyran compound represented by the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 are each selected from the group consisting essentially of hydrogen, a stable organic radical, a heterocyclic group, a halogen, a nitrogen-substituted group, and a nitrogen-substituted ring compound and wherein A is a substituted divalent aromatic radical that includes substituents selected from the group consisting essentially of hydrogen and the stable organic radical.

Abstract: A packaging arrangement for the containment in a blister package of at least one hydrophilic contact lens in a sterile aqueous solution. Provision is made for incorporating support structure in the form of stiffening groove or wall elements in flanges of base members of the blister packages to facilitate an improved attachment between the base members of the blister packages housing the contact lenses, and a flexible cover sheet utilized for sealing engagement with the base members while incorporating additional strength to the blister package structures.

Abstract: A lateral-emitter electron field emission device structure incorporates a thin film laminar composite emitter structure including two or more films composed of materials having different etch rates when etched by an etchant. In its simplest form, the laminar composite emitter consists of two ultra-thin layers, etched differentially so that a salient remaining portion of the more etch-resistant layer protrudes beyond the less etch-resistant layer to form a small-radius tip. In a preferred form of the laminar composite emitter, it is a multi-layer laminar emitter, of which the most etch-resistant layer is doped-diamond. The diamond layer is doped using one or more N-type dopants. In this preferred emitter structure, the edge of the thin film diamond layer is the dominant electron emitter with a very low (nearly zero) work function. Hence the new device can operate at applied voltages substantially lower than in prior art. The laminar structure may be a sandwich structure with three layers.

Abstract: An apparatus for molding polystyrene mold halves which are used, for subsequent molding of a soft contact lens. The apparatus is designed with superior heat conduction capacity so as to minimize the molding cycle time, while simultaneously producing uniformly precise and accurate optical quality surfaces. Molten polystyrene is provided via a hot runner system to a plurality of mold cavities. In a specific variation, the convex surface provides the optical quality surface to the concave surface of the mold half produced thereby. The structural element which defines the convex surface includes a hollow cylindrical bushing and a removable power insert mounted therein, which may be changed so that the prescription strength of the contact lens to be formed by the mold may be varied. In a first embodiment, the power insert includes only a convex surface at its operational end.

Abstract: An endoscopic sheath support assembly for supporting a sheath in a substantially fixed position for installation and removal of an endoscope insertion tube. The support assembly has an elongated rigid support tube with an interior area, and the sheath is in the interior area. The support tube is releasably connectable to a vacuum source to create a partial vacuum to expand the sheath. The distal end of the support tube has a pair of opposing openings that are adjacent to the distal end of the sheath when the sheath is positioned in the support tube. A resilient sheath retaining sleeve sealably covers the opposing openings. The resilient sheath retaining sleeve is movable by the partial vacuum to a retaining position wherein portions of the sleeve extend through the openings and engage the distal end of the sheath to retain the distal end of the sheath in a substantially fixed position relative to the support tube.

Abstract: Described herein are photochromic compounds or a structural isomer of the photochromic compound, the photochromic compounds represented by the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6, R.sub.8, A, B, C, and D are each selected from the group consisting essentially of hydrogen, a stable organic radical, a heterocyclic group, halogen, a nitrogen-substituted radical, and a nitrogen-substituted ring radical.

Abstract: A fabrication process is disclosed using process steps (S1-S18) similar to those of semiconductor integrated circuit fabrication to produce lateral-emitter field-emission devices and their arrays. In a preferred fabrication process for the simplified anode device, the following steps are performed: an anode film (70) is deposited; an insulator film (90) is deposited over the anode film; an ultra-thin conductive emitter film (100) is deposited over the insulator and patterned; a trench opening (160) is etched through the emitter and insulator, stopping at the anode film, thus forming and automatically aligning an emitting edge of the emitter; and means are provided for applying an electrical bias to the emitter and anode, sufficient to cause field emission of electrons from the emitting edge of the emitter to the anode. The anode film may comprise a phosphor (75) for a device specially adapted for use in a field emission display.