Abstract: An electro-optical signal translator, signal translator design features, methods of fabrication, alignment techniques and alignment apparatus that utilize, with the exception of output optical fiber to transmitter module coupling, passive assembly techniques that are compatible with assembly line operations to produce high performance electro-optical signal translators.

Abstract: An electro-optical signal translator, signal translator design features, methods of fabrication, alignment techniques and alignment apparatus that utilize, with the exception of output optical fiber to transmitter module coupling, passive assembly techniques that are compatible with assembly line operations to produce high performance electro-optical signal translators.

Abstract: An apparatus and method are disclosed for use in an antenna remoting system. The apparatus comprises a single source of laser light having an output characterized by two distinct polarizations and at least two closely separated frequencies, and a fiber optic communications link joined to the source and having a modulator therein which is driven by a radio frequency information signal such that said modulator produces a beat frequency output which is a function of the sum of the two closely separated frequencies.

Abstract: An electro-optical modulation system comprising an optical modulator for pulse-modulating an incoming light beam in response to a pulsed RF input signal and to a bias signal and for producing a pulse-modulated optical output which is characterized by a plurality of enveloped pulses, optical detector for producing an electrical signal which is representative of the output from the optical modulator, average detecting device for producing pulse envelope signals which are representative of the envelopes of the pulses, and a bias control circuit, using a plurality of pulse envelop signals, for producing the bias signal as a function of the pulse envelopes.

Abstract: Methods and apparatus for providing substantially complete correction of thermally-induced aberrations of the gain medium in an end-pumped laser system with at least one aspheric surface that is positioned within the optical cavity of the laser system. The at least one aspheric surface is shaped to substantially cancel all of the thermally-induced aberration of the gain medium at the normal power level of the laser system.

Abstract: Methods and apparatus for propagating robust scanning signals in pixel addressing operations in a pixel-to-pixel sequence that produces a predetermined pattern of alternating colors in an image signal so that a single channel, sequential color signal is generated from the pixel addressing operations in optoelectronic image transducers to reduce complexity and improve image fidelity.

Abstract: An upconversion laser system that uses solid state components throughout and achieves such operation with a continuous or quasi-continuous single band infrared pumping source using successive energy transfers between the sensitizer and activator in the host of the lasant upconversion material.

Abstract: Disclosure is made of a laser system comprising a non-linear crystal that converts light at a fundamental wavelength to light at a harmonic wavelength and that has a thickness such that there is a phase mismatch between light at the fundamental wavelength and light at the harmonic wavelength in said crystal; first means for forming one of a travelling wave optical cavity and a standing wave optical cavity at the fundamental wavelength; and second means for forming one of a travelling wave and a standing wave optical cavity at the harmonic wavelength, the first means and said second means are located relative to the faces of said crystal such that the total phase mismatch of the light at the fundamental wavelength and the light at the harmonic wavelength, in the round trip path through the crystal and between each face of the crystal and the first means and the second means, is equal to an integral multiple of 2.pi..

Abstract: An electro-optical signal translator, signal translator design features, methods of fabrication, alignment techniques and alignment apparatus that utilize, with the exception of output optical fiber to transmitter module coupling, passive assembly techniques that are compatible with assembly line operations to produce high performance electro-optical signal translators.

Abstract: A method for cleaving a semiconductor crystal body having a first surface and an opposite second surface, comprising the steps of forming a channel on the first surface of the semiconductor, scribing a portion of the second surface opposite the channel on the first surface, and mechanically cleaving the semiconductor along a plane defined by said channel on the first surface and said scribe on the second surface.

Abstract: A method is provided for controlling the output frequency of a laser having a lasant gain medium which is characterized by at least two gain curve distributions over a range of lasant frequencies and having a laser cavity which is characterized by at least one resonant frequency within one gain curve distribution. The method comprises the steps of: locating in the laser cavity a first Lyot filter which has a transmission band which favors the frequency range of one gain curve distribution in preference to the frequency range of the other gain curves; and locating in the cavity a second Lyot filter which has a transmission band which favors said one resonant frequency within the frequency range of the one gain curve, whereby an essentially single frequency output is obtained.

Abstract: A photovoltaic cell for use in a single junction or multijunction photovoltaic device, which includes a p-type layer of a semiconductor compound including silicon, an i-type layer of an amorphous semiconductor compound including silicon, and an n-type layer of a semiconductor compound including silicon formed on the i-type layer. The i-type layer including an undoped first sublayer formed on the p-type layer, and a boron-doped second sublayer formed on the first sublayer.

Abstract: A method and apparatus for reducing the effects of relative intensity noise in a diode laser system by sensing the light output of diode laser system and producing an electrical feedback signal; amplifying the feedback signal over at least two different parts of a frequency band that includes the Relaxation Oscillation Frequency of the laser system; shifting the phase of each of the amplified feedback signals over the frequency band; and superimposing onto the current supplied to the laser diode a current signal that is a function of each of the phase shifted and amplified feedback signals.

Abstract: Nonintrusive sensors capable of measuring various storage cell parameters such as voltage, state-of-charge, electrolyte level, internal resistance, and temperature are attached to a monitoring module which gathers and processes signals representative of information concerning the condition of electrolytic storage cells and transmits the information to a central computer for further processing. In response to commands issued by the central computer, appropriate maintenance and/or repair operations can be initiated. Alternatively, the system described can be used to automatically perform such maintenance tasks as checking and adding electrolyte levels, reducing the voltage in cells whose output voltage is too high, and leveling the state-of-charge of each cell in an array of electrolytic storage cells. The system can monitor other functions of the electrolytic storage cells, including the evolution of hydrogen gas and the accumulation of sediments in individual electrolytic storage cells.

Abstract: An optical mounting is described and which has two opposite faces, a reference axis which is generally perpendicular to the faces, at least one arcuate slot which joins the faces and which defines an interior part and an exterior part and means for moving the interior part relative to the exterior part. The slot has sufficient length and width so as to allow limited movement between the two parts. The interior part has an aperture located therein for receiving an optical component.

Abstract: Methodology and apparatus for producing pulsed, single longitudinal mode optical energy over a widely tunable range of wavelengths by optical parametric frequency conversion.

Abstract: Methods and appartus for upconverting laser sources and amplifiers that use solid state components throughout and achieve such operation with a continuous or quasi-continuous single band infrared pumping source using successive energy transfers between the pumping radiation and activator in the host of the lasant upconversion material under ordinary operating conditions.

Abstract: A method and apparatus for automatically maintaining the length of a laser cavity in a laser system in an optimum single length mode regardless of changes of frequency in the dispersive optics feedback, by sensing a group of pointing directions of a laser beam over a determined range of operating conditions, determining the average pointing position of the laser system for the group of sensed pointing directions and adjusting the length of the laser cavity to conform the pointing direction of the laser system to the average pointing direction.

Abstract: A method and apparatus for injecting a pump beam into a multi-pass amplifier to achieve a high degree of pump-input beam overlap.

Abstract: An end-pumped laser oscillator having an amplifier including a solid-state gain medium. Pump beams, which are generated by two groups of laser diode bars placed between the optical elements defining the optical resonator, are directed onto opposite end surfaces of the solid-state gain medium, which intersect the optical axis of the optical resonator. The laser diode bars of each group are circumferentially distributed about the optical axis in a uniform pattern and at the same distance along the optical axis from the gain medium. One group of diode bars is located to one side of the gain medium and the other group is located to the other side of the gain medium. Pump beam energy is thereby effectively and efficiently directed onto both end surfaces of the solid-state gain medium from a plurality of laser diode bars allowing the output power produced by the gain medium to be scaled to the thermal limits of the gain medium.