Abstract: Disclosed is optical data signal apparatus for optically coupling a plurality of data channels between stationary and rotating systems. The optical data signal apparatus is useful in a rotary head scanner for coupling a plurality of data channels between a rotating head wheel, having a plurality of magnetic record/reproduce heads, and stationary signal processing circuitry. Each data channel of the apparatus includes an optical data signal transmitter, an optical data signal receiver and an optical coupling element for causing an optical data signal transmitted by the transmitter to be focused on the receiver. The plurality of optical coupling elements are preferably annular and arranged concentrically in a plane. Each optical coupling element focuses the optical data from a transmitter to a respective receiver which is positioned off axis with respect to the central axis of the concentric optical elements. Preferably the optical elements are holographic optical elements.

Abstract: A reflector for an excimer laser is composed of an aluminum layer deposited on a substrate and at least two pairs of dielectric multilayers of high refractive index material and low refractive index material alternately piled on the aluminum layer, and optical thickness of the respective layers of an outer pair of the dielectric multilayers are deviated from .lambda./4 and total optical thickness of the outer pair is made to be .lambda./2.

Abstract: A radio frequency excited carbon dioxide laser (50) is stabilized by sensing (66) variation in output power to generate a feedback signal (68,78 ) that is employed to vary amplitude of the radio frequency exciting signal from a power source (62). Frequency modulation of the laser output is achieved by varying the amplitude of the radio frequency signal from a power source (62) in response to a frequency modulating control signal from a modulation source (74). Both stabilization and frequency modulation are accomplished by combining the sensed power feedback signal with the frequency modulation control signal in a summing circuit (70) and employing the combined signal to vary magnitude of the radio frequency exciting signal.

Abstract: He--Ne gas discharge tube having a cylindrical tube body with an inside cathode cylinder and end walls which are inserted into ends of the tube body and which have for two capillary tubes, outside ends of which are closed by means of Brewster windows, exhaust pipe and connecting pin for the cathode cylinder. The tube, the end walls and the capillary tubes consist of calcium alkalisilicate glass or calcium alumosilicate glass. The end walls are sealingly connected by means of glass solder to the tube body, the capillary tubes, the exhaust pipe and the cathode connecting pin. The He--Ne gas discharge tube is characterized by a high helium tightness.

Abstract: A strain compensated fiber optic cable composed of a hollow central member made from an elastic material capable of being physically enlarged, such enlargement capable of being at least partially reversed upon demand; and, a plurality of optical fibers having a first pitch diameter disposed, either in the sidewall of the central member, or on the outermost surface of the central member, so that upon enlargement of the central member, the first pitch diameter of the optical fiber can be changed to a second pitch diameter and upon reversal of the enlargement, the second pitch diameter can be changed to either the first pitch diameter or another pitch diameter.

Abstract: A laser resonator has a semitransparent outlet mirror and a first mirror, with an active element between the mirrors, all the elements arranged perpendicular to the optical axis of the resonator. A shutter is provided behind the first mirror and a second mirror is arranged behind the shutter, perpendicular to the optical axis of the resonator. The second mirror is fully reflective for radiation with stronger laser transition and the first mirror is fully reflective for radiation with weaker laser transition and fully penetrable for radiation with stronger transition. The resonator can change frequency simply by opening or closing the shutter. It can be advantageously used, for example, in the design and construction of laser scalpels.

Abstract: A laser beam recording method and apparatus are constituted for recording an image by obtaining a laser beam whose optical intensity is modulated by controlling a drive current for a semiconductor laser on the basis of a light emission level instructing signal corresponding to an image signal, and scanning the laser beam on a photosensitive material. The optical output is stabilized by detecting the optical intensity of the laser beam and feeding back a feedback signal corresponding to the detected optical intensity to the light emission level instructing signal. A filter circuit formed so that the gain gradually increases from near to a cutoff frequency of a circuit for the optical output stabilization toward a higher frequency side is disposed in a stage prior to the circuit for the optical output stabilization.

Abstract: A distributed feedback semiconductor laser device comprising a laser oscillation region and a distributed reflector which are provided in a laminated crystal structure, and comprising facets at both the ends, wherein a light emitting face is disposed at one or both ends of the laser oscillation region, the face being parallel to the lamination direction and intersecting with the light emitting direction at an angle which is 90 degrees minus the Bresster angle.

Abstract: An ion laser includes a magnetic field source to generate an axial magnetic field in one region and transverse field components outside the region, the magnetic field source being shorter than the discharge channel of the laser. Axially spaced permanent magnets in the proximity of the discharge channel are adapted to the laser structure and can include magnetic rings or ring structures. The magnets are preferrably adjacent the cathode end of the discharge channel.

Abstract: An ultrasonically modulated laser comprises a laser oscillation tube including opposing ends for generating a beam of planar polarized light having a plurality of wavelenghts; an output mirror at one end of the tube for reflecting the light beam; and a modulation device at the other end of the tube for simultaneously modulating a plurality of wavelengths of the light beams, including an acousto-optical prism having an incident surface for separating the beam into multiple wavelength components, a total reflection mirror for receiving and reflecting selected wavelength components impinging on the incident surface from the tube at a predetermined angle, and an ultrasonic transducer for generating standing means perpendicular to the selected wavelength components for modulating the reflected selected wavelength components.

Abstract: An optical wavelength conversion device is composed of a nonlinear optical material, and a first cladding layer having a refractive index lower than the refractive index of the nonlinear optical material and covering the nonlinear optical material, thereby to convert a fundamental wave entering the optical wavelength conversion device to a second harmonic, to guide the second harmonic through the first cladding layer, and to radiate the second harmonic. A second cladding layer formed of a material having a refractive index lower than the refractive index of the first cladding layer is provided outside of the first cladding layer, thereby to protect the first cladding layer.

Abstract: Coherent coupling of a plurality of reflection type optical gain elements with a seeding laser is provided by illuminating the optical gain elements with fanned laser light scattered from a photorefractive medium. The reflection type optical gain elements have an anti-reflective end nearer the photorefractive medium and a reflective opposite end. The optical gain elements also illuminate the photorefractive medium. The resultant amplified and coherent light beam has its wavefront cleaned up with a photorefractive oscillator to provide a diffraction limited or nearly diffraction limited beam.

Abstract: Light relative to non-modulated output light emitted from a semiconductor laser is applied to an absorption cell. Frequency modulating signals are converted into amplitude modulation signals of the output light through a modulating means by utilizing absorptive properties of the absorption cell. Transmissive light outputs of the absorption cell are synchronously rectified by a lock in amplifier, and an electric current supplied to the semiconductor laser is controlled so that the output signals of the lock in amplifier are arranged to be a predetermined value. The wavelength of the output light is locked to the absorption line of the standard substance in the absorption cell. Advantageously, the invention stabilizes the instantaneous value of the oscillation frequency.

Abstract: An optically uncoupled laser array is modified at its current confinement geometry to introduce nonuniformity in effective optical cavity width and/or length among the different lasers comprising the laser array. An array laser comprising a plurality of spaced lasing elements with an optical cavity for generating and propagating radiation under lasing conditions with each of the laser elements being optically uncoupled from one another is enhanced by an extended spectral emission linewidth and reduction in temporal coherence. This extended spectral emission linewidth and reduction in temporal coherence is accomplished by changing the gravity gain or loss for at least a majority of the laser elements relative to each other whereby a different longitudinal mode(s) of operation and frequency of operation exist for each such laser element.

Abstract: This invention relates to an improved method for producing pulsed trains of light within a cavity which comprises repeatedly incrementally increasing the frequency of a constant wave of light circulating within the cavity and combining the frequency-shifted beams to produce at least one pulsed train output thereof. This can be done in either a passive or active cavity.

Abstract: A flowing gas laser, of the kind in which gas flows continuously through the lasing region and is circulated through the heat exchanger for cooling before being returned to the lasing region, comprises a resonator module and a blower module. The optical components of the laser are mounted on an outer surface of the resonator module, and the resonator module has an interior structure for conducting the circulating gas to the lasing region. The blower module has heat exchange structure for cooling the circulating gas and has a blower for pumping the circulating gas. The blower module is physically separated from the resonator module to prevent the heat and vibration of the blower module from distorting or otherwise affecting the structure or the performance of the optical components. Ducting the interconnects the resonator module and the blower module for circulating the gas between these modules.

Abstract: A high-speed axial-flow gas laser generator has a plurality of anodes radially provided at the inlet section of the laser tube, and a ring-shaped cathode is provided on the gas discharge section side of the laser tube. On the upstream side from the anodes, viewed from the laser gas flow in the laser tube, a nozzle is provided which imparts a spiral rotary motion to the gas flow in the laser tube.

Abstract: A ring resonator waveguide for a laser gyroscope comprises a ring of waveguide material (2) formed around the inside or outside surface of a hollow cylinder (3) or ellipsoid (4). Such a ring resonator waveguide is made by providing a hollow cylindrical substrate (1), depositing waveguide material (2) on the inside or outside surface of the hollow cylindrical substrate (1), heating the substrate (1) and blowing it to form a cylindrical or ellipsoidal (4) member, and cutting a circular section (5, 6) from the cylindrical member (3) or from a central portion of the ellipsoidal member (4).

Abstract: A free electron laser (FEL) is disclosed in which the phase of the output electromagnetic beam is inherently adjustable without the use of any extraneous optical phase shifting materials. This is accomplished by implementing the FEL as a pair of series-connected wiggler cavity sections, and varying the relative phases of the bunched electron flow in the first cavity section relative to the second. In a preferred embodiment a series of electrodes are provided in a transition region between the two cavity sections, and variable voltages are applied to the electrodes to electrostatically control the electron transit time through the transition region, and the electron velocity upon exiting from that region. This translates into a control over phase and frequency.

Abstract: A single frequency adapter for a gas laser comprises a jacket for engaging and being secured to the casing surrounding the gas laser. An induction coil is fixed within the jacket and positioned to surround the hollow mirror mount at one end of the laser tube while being outwardly spaced from the hollow mount. A power supply and modulator apply an alternating current to the induction coil.