Abstract: An optical device comprising an optical waveguide having a varying refractive index has low radiation loss. The waveguide may be either curved or tapered.

Abstract: In an electrochromatic, transparent layer system comprising at least one electrochromatic layer (2), two electrodes (3, 5) separated by a hydrogen ion supplying layer which simultaneously is a hydrogen ion storing layer (4), there is located, seen in the direction of light incidence through the layer system, a further hydrogen ion conducting layer (6) (e.g. of SiO.sub.2) behind the electrode (5), behind which a further electrode (7) is arranged. The electrode (7) is capable of oxidizing hydrogen diffusing from within the system into hydrogen ions. For this purpose, a protective voltage is applied between electrode (5) and electrode (7) such that the third electrode (7) forms the positive pole.

Abstract: A single-mode electro-optic switch (10 or 10') including a graded index layer (14b or 14b'). Two electro-optic embodiments are disclosed. The first embodiment includes a substrate (12) and a planar waveguide (14) atop the substrate (12) including a graded index layer (14b) sandwiched between a pair of lower refractive index layers (14a and b 14c). The substrate (12) preferably forms anisotropically etched V-grooves (38) suitable for receiving fibers (50) and (52) and for registering the cores of the fibers with the middle layer (14b). The first embodiment of the switch includes a single input port and a pair of output ports, wherein when the switch is energized, light is reflected away from the first output port and toward the second output port.

Abstract: A reticle design is provided for step and repeat projection aligners which, when patterned on a wafer (10), allows quick macroscopic evaluation of best focus for used in fabricating integrated circuits. The reticle pattern consists of opaque lines and spaces of widths slightly above the resolution limit of the resist/aligner system. The macroscopic determination of best focus, being macroscopically visible, eliminates the need for microscopic determination, thereby providing a quick and easy method. The best focus determination is made by forming an array (22) of resist fields (14') on the wafer, subjecting each field to a different focus and exposure. Upon development, those fields away from the best focus and at the larger exposure doses will be removed, leaving a parabola (24) of fields whose apex (26) is at high exposure. Best focus is the focus setting used to print the row of fields (B) containing the apex.

Abstract: There is disclosed an electrochromic element in which an oxidative color-forming layer is composed of an organic material and a reductive color-forming layer is composed of an inorganic material. The electrochromic element comprises a pair of electrodes, at least one of which is transparent, the oxidative color-forming layer composed of organic materials such as polyaniline, polypyrrole, polythiophene, etc. and the reductive color-forming layer composed of inorganic materials such as WO.sub.3, MoO.sub.3, TiO.sub.2, etc. formed between the pair of electrodes to face to each other, and an electrolytic solution or a solid or semi-solid electrolyte layer sealed between the both color-forming layers.

Abstract: An electronic display device having a polyaniline film coated on a transparent electrode. The film has electrochromic properties and will display at least three distinct reproducible color changes.

Abstract: Optical radiation can be efficiently removed from, or injected into, single mode optical fiber at an intermediate point along the fiber, by causing quasi-resonant coupling of the guided mode LP.sub.01 to an appropriate tunneling leaky (TL) mode, e.g., LP.sub.11. Such coupling is caused by means of a "grating" in the fiber, with the grating being formed by impressing a periodic (or pseudo-periodic) modulation on the fiber, or by causing a periodic (or pseudo-periodic) variation of the refractive index of the fiber by means of the photoelastic or the photorefractive effect. The nominal grating spacing .LAMBDA.(z) is chosen such that .OMEGA..sub.o =(2.pi./.LAMBDA.)>.beta..sub.01 -2.pi.n.sub.cl /.lambda..sub.o, where .LAMBDA. is the average grating spacing, .beta..sub.01 is the propagation constant of the LP.sub.01 mode, n.sub.cl is the refractive index of the fiber cladding, and .lambda..sub.o is the wavelength of the radiation to be coupled from or into the fiber. Furthermore, .LAMBDA.

Abstract: A semiconductor amplifying device 1 comprises, a substrate 2, a first optical waveguide 7 on the substrate 2 for transmitting an optical signal, a second optical waveguide 8 on the substrate 2, a third optical waveguide 11 on the substrate 2 forming an optical coupling with the first optical waveguide 7 along an interaction length and constructed as a semiconductor optical amplifier 11 that receives and amplifies at least a portion of the optical signal to the first waveguide 7, and antireflective means 16 covering light emitting edges 7a, 8a, 11a, 3a at corresponding ends of the respective waveguides 7, 8, 11 and an optical transmitting medium 3, the second optical coupling having a phase mismatch selected for a wavelength of the optical signal to provide for a power gain in the first optical waveguide 7 attributed to an amplified portion of the same wavelength of the optical signal coupled back from the amplifier 11.

Abstract: A crossover arrangement for optical conductors, each in the form of a rod of light-transmissive material, includes a multifaceted, e.g. polyhedral member having pairs of mutually parallel opposed facets. Each pair of facets extend in a direction transverse, preferably perpendicular, to that in which a second pair of facets extend. The end face of each optical conductor is abutted against one of the facets of the polyhedron. Each facet has a coating of a material having a lower refractive index than that of the polyhedron or the optical conductors. Light entering the polyhedron from one conductor passes across the polyhedron and into the opposite conductor, being constrained to stay within the polyhedron by the coatings on the side facets. Preferably the polyhedron member is a cube and the optical conductors are of square cross-sectional shape.

Abstract: The present invention relates to an economically manufactured monomode quartz glass light waveguide and to a method for producing it, particularly for the spectral range around 1.3 .mu.m and around 1.56 .mu.m, with optical transmission losses less than 0.5 dB/km. This is accomplished by a light carrying core region surrounded by inner and outer (quartz glass) jacket regions. The outer diameters of the inner jacket region and of the core region have a ratio which lies in a value range from about 1.8 to about 3.5.

Abstract: An electrically controlled integrated optical switch having a body made up entirely of crystalline silicon. More specifically, the body has a pair of channel waveguides intersecting in an X-like configuration forming therein an intersection crossover region. A first electrode is positioned on the intersection crossover region and a second electrode is positioned on the bottom of the body opposite the intersection crossover region. A controllable current/voltage source is electrically connected to the electrodes in order to alter the index of refraction of the intersection crossover region by carrier injection in order to selectively switch optical signals between diverging waveguides.

Abstract: A wavemeter/frequency locking technique suitable for indirectly locking an optical frequency f.sub.0 to a radio frequency f.sub.1 or for locking the radio frequency to the optical frequency. A beam of optical frequency f.sub.0 is phase modulated by a signal of average frequency f.sub.1 that is itself modulated at frequency f.sub.2. The modulated beam is passed through a filter to a detector to produce a detector output signal that has components at linear integral sums of f.sub.1 and f.sub.2. A pair of control signals are generated that are proportional to the amplitude of two of the components of the detector output signal. These control signals are separately used in a pair of servo loops to separately establish fixed values of f.sub.0 /f.sub.f and f.sub.1 /f.sub.f, where f.sub.f is a characteristic frequency of the filter. A method is presented for stepping the value of f.sub.0 /f.sub.f to another value and measuring f.sub.1 /f.sub.2 at each of these values, thereby enabling the value of f.sub.

Abstract: An electrochromic display device in which an electrolyte is disposed between a display electrode and a counter electrode, and an electrochromic substance layer is formed at least to the inside of said display electrode, wherein the counter electrode comprises a layer containing a white redox substance. Since the white redox substance layer is formed to the counter electrode, white background plate is no more necessary which enables to reduce the fabrication cost and give a great feasibility for the design of ECD.

Abstract: A connector for a multifiber optical cable in which each of the fibers is retained on a common housing which includes receptacle portions for retaining, respectively, a fitting for the cable, and each ferrule to which respective optical fibers are secured. The housing is preferably molded of a plastic material with intergral constituents for retaining the ferrules and cable fitting. The ferrules extend from the housing and can be secured to respective optical connectors or other devices.

Abstract: A mounting arrangement for mounting an optical conductor on a "photonic" backplane provides for simple, accurate positioning during installation and easy access to, and removal of, the optical conductor when in service. The optical conductor constitutes a "busbar" in that it has a series of reflector surfaces spaced along its length to permit distribution or aggregation of several light signals. In one embodiment, an individual support is provided at each reflector/circuit card location. Each support is a seating member which houses a lens to couple light between the optical conductor and the circuit card. In another, preferred, embodiment the optical conductor is housed in a channel in a guide rail mounted upon the backplane. Separate cover members are releasably mounted upon the guide rail adjacent each circuit card. Each cover member has an aperture and lens to couple light between the reflector and the circuit card.

Abstract: To make a low loss connection between the core (5) of a single mode optical fibre (1) and a waveguide (2) on a waveguide substrate (3), a support block (4) which straddles the waveguide (2) is mounted on the waveguide substrate (3). The end-face (6) of the optical fibre (1) is fixed to both the waveguide substrate (3) and the support block (4) with transparent, light curable, adhesive (8). The support block (4) may be affixed to the substrate (3) with the same adhesive as is used to fix the optical fibre (1) to the substrate (3).

Abstract: An optical reading head is an optical reader for photoelectric reading of images on a medium, comprising a plural light-emitting optical fibers for transmitting beams of light from light emitting elements to the surface of the medium, and plural light-receiving optical fibers for transmitting beams of reflected light from the medium surface to light-sensitive elements. The ends of the light-emitting and light-receiving optical fibers opposite to the medium surface are positioned in first and second rows, respectively, at a predetermined pitch. The ends of the light-receiving optical fibers are displaced relative to the ends of the light-emitting optical fibers along the first and second rows by a distance equal to a half of the predetermined pitch. Also disclosed is an optical reader comprising the above-described optical reading head, and a control device for controlling the operations of the light emitting elements, so that the resolution of the reading head is variable in two steps.

Abstract: A coupling device for forming optically efficient end-to-end connections between optical fibers having a common core and cladding geometry but different relative dimensions and cross sections includes forming a segment of optical fiber having the same general geometry of the fibers to be coupled but which varies between relatively enlarged and reduced cross sections along its length. The coupling device is severed along its length at appropriate points to match the relative cross sections of each fiber to be coupled to thereby allow a butt type coupling between optical fibers of the same general geometry but with differing cross sectional areas. The coupling devices may be manufactured by drawing a starting fiber having the same geometry of the fibers to be coupled and varying the drawing speed to create enlarged and reduced cross section portions. The starting fiber may then be severed at the reduced cross section portions to provide the coupling device.

Abstract: Disclosed is a nonglaring mirror which is an electrochromic device in principle. The mirror comprises a transparent front substrate laid with a transparent first electrode film, a back substrate laid with a second electrode film which is opposite and spaced from the first electrode film, first and second electrochromic layers formed on the first and second electrode films, respectively, and an electrolyte liquid which fills up the space between the two substrates. A reflecting surface is provided by using a transparent sheet as the back substrate and coating the rear surface of the back substrate with a reflecting metal film, or by using a reflecting metal film as the second electrode film. One of the first and second electrochromic layers is formed of a polymer of a conjugated compound, such as substituted or unsubstituted triphenylamine, and the other is formed of a transition metal oxide such as WO.sub.3. In the initial state both the first and second electrochromic layers are colorless and transparent.

Abstract: An apparatus (10) for measuring the magnification power of a magnifying aid (14) is disclosed. The apparatus (10) includes an optical system (12) having an objective lens (34) focused at infinity on a reticle. The reticle (20) is positioned in the line of sight of the optical system (12). The reticle (20) is precalibrated such that the magnification power of a magnifying aid (14) may be determined. Also, disclosed is a method of calibrating the optical system (12) and a method of measuring the magnification power of a magnifying aid (14).