Abstract: An optical transmitter includes a transmitting unit and a processing unit. The transmitting unit transmits multiple optical synchronization pulses at a first intensity, and transmits multiple optical quantum cryptographic key distribution (QKD) pulses at a second intensity. The processing unit encodes a cryptographic key symbol in a quantum state of each QKD pulse of the QKD pulses, and delays transmission of each of the multiple optical synchronization pulses a derived interval after transmission of a corresponding one of the multiple QKD pulses.

Abstract: A method and apparatus is disclosed for signaling a switch of the target destination of a data packet having a header specifying the destination address and an information frame. The data packet along with a separate instance of the header is subcarrier multiplexed and simultaneously transmitted. The separate header is transmitted at a lower speed than the data packet permitting detection and processing by less expensive receivers.

Abstract: An optical preamplifier includes a semiconductor optical amplifier monolithically integrated with an optical detector and electrically isolated from the detector by an isolation region. The isolation region consists of a low-loss, preferably transparent, insulating material whose index of refraction is matched to at least the refractive index of the amplifier, leading to reduced facet reflectivity at the amplifier output facet. Alternative device structures may include a waveguiding layer in the isolation region, a grating integrated with or following the optical amplifier, and a tuning region positioned between the amplifier and isolation region for filtering spontaneous emission.

Abstract: A monolithically integrated optical preamplifier comprises an amplifying region, an optical detection region for detecting amplified light, and an optically transparent and electrically insulating isolation region interposed between the amplifying and optical detection regions. The amplifying region achieves reduced facet reflectivity by being designed to have a large spot size, single-traverse mode waveguide amplifier oriented at an angle with respect to a crystal plane through the preamplifier. The isolation region is preferably an air gap.

Abstract: A system for measuring the frequency response of an electrooptic device, such as an optical detector, includes an optical amplifier for generating an optical white noise spectrum that is delivered to the detector. In a first embodiment, an optical amplifier or a luminescent fiber amplifier generates a white noise signal due to spontaneous-spontaneous beat noise emission, while a second embodiment utilizes the signal-spontaneous and spontaneous-spontaneous beat noise emissions generated by an optical amplifier driven by a laser source. The frequency response of the detector is determined from a measurement of the detected noise signal wherein any roll-off in the response must be due to the detector since the originally generated noise spectrum is flat.

Abstract: An acoustic to optical pulse code modulating transducer includes a microphone housing. An optical fiber is supported, by suitable means coupled to the housing, at a position displaced from one end of the fiber so that the one end is oriented within the housing. Electromechanical transducing means, coupled to the housing, support a diode light source. The light source and the optical fiber are so aligned that, when the electromechanical transducing means is unexcited, light from the source is directed through the first end to the optical fiber. An acoustic diaphragm is affixed to the housing. The diaphragm is coupled to the fiber at a point between the aforesaid position and the first end. The electromechanical transducing means is excited so that the light source is vibrated along a path perpendicular to the axis of the optical fiber. The light source is suitably electrically powered.

Abstract: A microsphere bead coupling lens can be mounted onto an end of an optical fiber after the end is initially prepared by cleaning and cleavage. An adhesive is first applied to the cleaved end. The applied adhesive end of the optical fiber is then approximately centered over a microsphere bead to be mounted. The fiber is lowered until the adhesive on the end contacts the bead. The fiber is then raised whereby the adhesive on the end holds onto the bead by surface tension so that the bead gets picked up as the fiber is raised; and, due to the combination of surface tension and gravity, the bead lens is moved by the adhesive until the lens is aligned with, or very close to, the central axis of the fiber. Subsequently, the adhesive on the fiber end is cured by means such as ultraviolet-curing or heat-curing.

Abstract: In an optical scanning apparatus for photolithographic processing of faceplates intended for color cathode ray tubes, a light beam from a source is first deflected through an angle related to a predetermined angle of incidence that an electron beam in an operating tube has with respect to a defined faceplate location, and then the deflection point is imaged onto or in the vicinity of the faceplate. This angle of incidence adjustment is accomplished for each faceplate location as the light beam is scanned over the surface of the faceplate. The light source, which is preferably a laser light source, creates a light beam having a wavelength spectrum which exposes the photosensitive material. The beam is deflected by a pair of orthogonally aligned mirrors which are rotated by galvanometers. Each galvanometer is driven by a current from an electrical control, the current being related to the proper angle of incidence for each faceplate location.

Abstract: An optical scanning apparatus for manufacturing cathode ray tubes having a faceplate with an inner surface layer of photosensitive material and an adjacent apertured mask wherein a light beam from a light source is applied to a deflection device controlled by a control circuit to effect deflection of the light beam at an angle related to the angle of incidence of an electron beam in a cathode ray tube. The deflected light beam is imaged onto the inner surface of the faceplate of the cathode ray tube through the apertured mask, and a device is provided for scanning the deflected light beam over the surface of the faceplate in a predetermined pattern to effect exposure of the photosensitive material in the proper locations for registration with the landing location of an electron beam in the cathode ray tube.

Abstract: One embodiment of the disclosed apparatus converges a beam of light to a point of focus and scans that point of focus through an arc at a predetermined radius. The beam of light is then imaged to another point of focus by a unitary power optical system. The second point of focus, therefore, also scans through an identical arc which is displaced by a selected distance along the optical axis from the first point of focus. A master mask for exposing a photoresist on a semiconductor wafer is located at the first point of focus and the semiconductor wafer whose layer of photoresist is to be exposed is located at the second point of focus. However, the mask and wafer are mounted in a different fixture which is radially translatable relative to the scanning beam of light so that a sequence of scans of the beam of light across the mask and wafer serves to illuminate all areas of the mask and to thereby image the information on the mask onto the photoresist layer on the semiconductor wafer.