Abstract: A method for fabricating an optical quality, free-standing, compliant parabolic membrane mirror using an inverted parabolic mandrel created by rotating a liquid confined to a cylindrical polymer and applying a reflective optical stress coating once the substrate has hardened. The stress coating applies a tensile force to the substrate that offsets the stress in the substrate that would otherwise decrease the convexity, and also generates a force to restore the membrane mirror to its original convex parabolic shape when the mirror is deformed by an external force.

Abstract: A polarization conversation device (PCS) wherein a series of slots are formed in a frame to orient coated glass plates with retarder elements positioned there between. The PCS components are assembled within the frame and cover plates are secured thereto in a fluid-tight manner forming a fluid tight enclosure for receiving an index-matching fluid for homogenizing the temperature at any bright spots.

Abstract: The invention relates to a retractable rear-view mirror for motor vehicles. Said rear-view mirror comprises a fixed base, a swiveling mirror unit and a rotation driving unit composed of a motor and a transmission. In order to minimize the friction losses while requiring a minimal space and providing a favorable assembling shape: a) the transmission of the rotation driving unit is a harmonic drive transmission having a central axis which is coaxial with the rotation axis of the mirror unit; b) said voltage wave transmission contains an eccentric means in its transmission casing, an elastic annular gear and two driven links which co-operate with said annular ring and have a different number of teeth; c) the eccentric means has a toothed work which engages the pinion gear of said motor; d) one driven link engages the base and the other driven link engages the mirror unit. The eccentric means is placed inside the elastic annular ring and the two driven links are placed outside of the elastic annular ring.

Abstract: The invention provides an optical filter having first wave retarding element for receiving an optical signal including a plurality of wavelengths, said first wave retarding element having a first periodic output response of a first phase versus wavelength for the optical signal. The optical signal is polarized when being launched into the first wave retarding element. A second wave retarding element receives the optical signal from the first wave retarding element. The second wave retarding element has a second periodic output response of a second phase versus wavelength for the optical signal. The first periodic output response and the second periodic output response are different from each other and non-integer multiples of each other. Advantageously, the gain flattening filter is tunable, cost effective, and compact in size. It is capable of producing any desired spectral curve without PDL by simply adjusting the angle of each wave retarding means.

Abstract: An overcoat protected diffraction grating. A replica grating having a thin aluminum reflective grating surface is produced by replication of a master grating or a submaster grating. The thin aluminum reflective surface may be cracked or have relatively thick grain boundaries containing oxides and hydroxides of aluminum and typically is also naturally coated with an aluminum oxide film. The grating is subsequently recoated in a vacuum chamber with a thin, pure, dense aluminum overcoat and then also in the vacuum the aluminum overcoat is coated with a thin film of MgF2. The grating is especially suited for use for wavelength selection in an ArF laser operating producing an ultraviolet laser beam at a wavelength of about 193 nm. The oxygen free aluminum overcoat prevents the ultraviolet light from causing damage by stimulating chemical reactions in grating materials under the aluminum grating surface or in the aluminum oxide film. The MgF2 additionally prevents oxidation on the surface, of the aluminum overcoat.

Abstract: A tunable Fabry-Perot filter includes an optical cavity bounded by a stationary reflector and a deformable or movable membrane reflector. A second electrostatic cavity outside of the optical cavity includes a pair of electrodes, one of which is mechanically coupled to the movable membrane reflector. A voltage applied to the electrodes across the electrostatic cavity causes deflection of the membrane, thereby changing the length of the optical cavity and tuning the filter. The filter with the movable membrane can be formed by micro device photolithographic and fabrication processes from a semiconductor material in an integrated device structure. The membrane can include an inner movable membrane portion connected within an outer body portion by a pattern of tethers. The tether pattern can be such that straight or radial tethers connect the inner membrane with the outer body. Alternatively, a tether pattern with tethers arranged in a substantially spiral pattern can be used.

Abstract: An optical filtering apparatus and method, wherein at least one polarizer is located in the path of radiation passing through a birefringent medium. The invention can be used to process complementary bands of spatial frequency spectra. The invention can be practiced using a polarizing beam splitter. The invention can also be practiced using an optical storage layer forming part of the birefringent medium.

Abstract: A wavelength division multiplexing device and method includes two prisms having a pair of coated, highly reflective opposed faces forming an etalon. A volume phase grating is sandwiched between the two prisms. The volume phase grating is positioned between the highly reflective opposed face portions so that a light beam incident on the etalon undergoes a preselected number of multiple reflections between the highly reflective face portions and a preselected number of traversals through the volume diffraction grating, whereby wavelengths satisfying a Bragg condition on each traversal are diffracted out of the volume grating means. One prism may be designed to separate TE and TM polarized light, and the other prism may be designed to combine the TE and TM modes so that the result is polarization independent. Each prism includes at least one transparent output face through which the separately diffracted wavelengths are transmitted at respective angles.

Abstract: The present invention provides a diffraction optical element comprising a first optical member having a first diffraction grating, a second optical member having a second diffraction grating, wherein the first and second optical members are stacked so that the first and second diffraction gratings face each other inside the stacked members and so that a space is formed between the diffraction gratings, and a sealing member for hermetically sealing the space between the diffraction gratings.

Abstract: A light-polarizing film is provided which possesses a light transmittance of not more than 0.3% at wavelengths of from 430 nm to 500 nm inclusive when irradiated with a linearly polarized light with a vibration plane parallel to an absorption axis of said film, and a light transmittance of not less than 77% at wavelengths of from 430 nm to 500 nm inclusive when irradiated with a linearly polarized light with a vibration plane perpendicular to the absorption axis of said film. When a light-polarizing plate comprising the light-polarizing film is applied to the liquid crystal panel for blue of a liquid crystal projector, the obtained liquid crystal projector displays images featuring bright and 15 natural color tones.

Abstract: A method and system for filtering an optical signal is disclosed. The method and system comprise providing a polarization beam splitter, first and second rotators, a liquid crystal tunable filter, and first and second prisms. The polarization beam splitter splits the optical signal into two components based on polarization. The first rotator rotates a polarization 45 degrees in a first direction and is located between the liquid crystal tunable filter unit and the polarization beam splitter. The liquid crystal tunable filter unit includes liquid crystal molecules aligned 45 degrees clockwise relative to the vertical direction and is placed between the first rotator and the second rotator. The second rotator rotates the polarization 45 degrees opposite to the first direction. The first prism is located near the second rotator, while the second prism is near the beam splitter.

Abstract: A method and apparatus for interference lithography utilize a fiber having a cladding region with axially formed holes surrounding a core region. The fiber emits an optical signal to perform interference lithography. A number of alternative variations in the size and arrangement of axially formed holes produces fibers having characteristics particularly adapted for receiving, communicating, and emitting optical signals for interference lithography.

Abstract: A temperature insensitive polarization filter is made by inter-digitally stacking two different types of birefringent elements having positive and negative thermal coefficients. This results in a net cancellation of the positive and negative thermal coefficients of the birefringent elements within the filter. The optical retardance of each type of birefringent element changes by an almost equal amount as the operating temperature changes, with one type of element shifting toward a larger optical retardance and the other type of element shifting toward a smaller optical retardance. However, the total retardance remains essentially constant. This assures that the filter can operate over a wide temperature range without shifting its spectral response.

Abstract: A prism includes a prism base member having first and second faces intersecting with each other and including calcium fluoride, an antireflection film for oblique incidence formed on the first face of the prism base member, and an antireflection film for 0° incidence formed on the second face of the prism base member. Each of the antireflection film for oblique incidence and the antireflection film for 0° incidence includes a high-refractive-index layer with a relatively high refractive index, and a low-refractive-index layer with a relatively low refractive index. The high-refractive-index layer includes thorium fluoride and the low-refractive-index layer includes aluminum fluoride.

Abstract: An optical device has a base body with a surface, a first optically effective, multilayer system in the base body, terminating at an intersection, and a second optically effective, multilayer system. The second system has a layer along the base body surface, spanning the intersection. The surface of the base body, including the intersection, are jointly treated by at least one of: milling, grinding, polishing, and lapping. A further base body with a further surface and a third optically effective system terminating at a further intersection area at the further surface also has a further layer between the second optically effective multilayer system and the further surface.

Abstract: A polarization splitter and combiner for processing a beam containing a first polarization and a second polarization to spatially separate these polarizations by using a birefringent element for receiving the beam and walking off the first polarization from the second polarization by an initial walk-off distance. A first lensing element with an optical axis is oriented to admit the first polarization at a first input point and output the first polarization at a first output angle to the optical axis and the second polarization at a second output angle to the optical axis. A second lensing element positioned after the first lensing element is oriented to receive the polarizations at input angles equal to their respective output angles, and outputs both polarizations at a first and second output point respectively. In a symmetrical arrangement, the first and second output points are separated by the initial walk-off distance.

Abstract: The invention is directed to a crimp plug having a front portion, a center portion, and a securing portion. A conductor receiving cavity extends from the front e into the center portion. A stop shoulder within the center portion provides transition from the conductor receiving cavity to a plurality of conductor receiving passageway extending to a rear end. Each conductor receiving passageway serves to properly position the conductors while the stop shoulder serves to control the insertion length. A securing portion extends from the center portion and provides for securing of the cable.

Abstract: Optical systems for use with reflective LCDs (8,9,32,34,36) are provided. The systems include a polarization beam splitter (5) which can be composed of polarization beam splitting cubes (26) having sheet polarizers (30) and/or half wave plates (28) at their mating surfaces. By orienting the half wave plates (28) so that they convert S polarization to P polarization and P polarization to S polarization, the polarization beam splitter (5) can provide a high contrast ratio at a viewing screen between light from the “on” and “off” pixels of the reflective LCDs (8,9,32,34,36).

Abstract: A motorcycle rear view mirror assembly for addition to motorcycles and like vehicles providing a view of both the rear sides, and directly behind and adjacent to the rear of the motorcycle which will increase the safety of the operator when changing lanes and will make the rider aware of vehicles approaching too close behind them. The device features a first mirror positionable to an angle to reflect the area to the side of a motorcycle into the view of the rider and a second mirror attached to said assembly adjacent to an outside edge of first mirror and a provision for adjustment of the face of the second mirror toward the inside edge of the first mirror to an operative angle between 3 and 25 degrees.

Abstract: A reflective liquid crystal display device (LCD) (40) includes: a substrate (60), a reflecting layer (61), a liquid crystal layer (62), an electrode layer (63), a color filter layer (64), an upper substrate (65), and a polarizer (66). The reflective liquid crystal display device further includes a holographic field lens (67). By providing the holographic field lens, the LCD can be used with a closely placed, offset light source (41), since the holographic field lens simultaneously concentrates light incident on the LCD and redirects it in a preferred direction. The holographic field lens can be provided within the structure of the LCD.