Abstract: The luminescent screen of a cathode ray tube includes an array of monocrystalline or amorphous phosphor rod-like elements which are covered with a reflective coating except for one end of each element which serves as an output face. The phenomenon of the light trapping is advantageously exploited to achieve enhanced brightness. The screen is illuminated with an electron beam which has an essentially oblong cross section and which is oriented along the elongated dimension of the elements. In one embodiment the elements comprise epitaxial Lu.sub.3 Al.sub.3 Ga.sub.2 O.sub.12 :Ce on the top of a YAG substrate, and a light absorbing layer of Lu.sub.3 Al.sub.3.5 Fe.sub.1.5 O.sub.12 is formed on the bottom of the substrate. A printer utilizing such a CRT is described. Also described is a configuration in which each of the rod-like elements functions as a laser.

Abstract: An ultra-compact laser scanner comprising a self-contained housing including a handle portion configured to be readily held within the hand of a person and a short length body portion projecting outward from the handle portion. A subassembly including a laser tube and associated power supply is mounted on a circuit board within the handle and can be readily removed therefrom. A signal processing subassembly is located within the body portion above the handle. A motor and optic system subassembly is also mounted within the body portion and is arranged to direct a beam of laser light from the laser tube through an arc out through a window in the front of the body portion of the housing to sweep across a bar code symbol at which the device is aimed. A beam width adjusting/beam blocking moveable curtain is mounted over the window.

Abstract: A split contact phased array laser comprising a plurality of parallel emitters under phase locked operation and productive of an output beam having a preferred emission wavelength and preferred far field mode of operation. The charge distribution profile in the laser is changed to cause the output beam to deflect and scan in the far field. The improvement in the laser is the provision of at least three independently current pumped segments formed transversely of said emitters wherein at least one of the segments is current pumped above threshold level sufficient to primarily determine the emission wavelength and mode of operation of the laser while the current supplied to the remaining segments is below this level and is varied relative to one another to cause the output beam to deflect and scan in the far field without substantial change to the emission wavelength and mode of operation.

Abstract: A write/read head comprises a laser whose resonator faces are formed by the storage medium and by a curved reflective surface which is positioned at a nominal distance from the medium and has a described residual radiant transmittance and a radius of curvature which is greater than the nominal distance. A mode diaphragm is provided between the active medium of the laser and the storage medium. Optical detector elements for the acquisition of position control signals and data read-out signals are arranged outside of the reflective surface and are symmetrically arranged with respect to the optical axis of the laser.

Abstract: A laser beam emitting apparatus includes a semiconductor laser, a photodiode for detecting the intensity of the laser beam, an amplifier for amplifying the detection signal from the photodiode, and a variable resistor connected to the amplifier for adjusting the gain of the amplifier. In one embodiment, these elements are provided in a unit structure so that the adjustment of the gain of the amplifier can be carried out in advance. In another embodiment, a collimating lens for collimating the laser beam emitted from the laser is also provided in the same unit. In another embodiment, a single-piece support is provided to support the semiconductor laser, the collimating lens, and an aperture plate formed with an aperture for shaping the collimated laser beam. As a modification, the single-piece support can be made dual in structure while maintaining the structural integrity of the support.

Abstract: By optically injecting a single end-element of a semiconductor laser array, both the spatial and spectral emission characteristics of the entire laser array is controlled. With the output of the array locked, the far-field emission angle of the array is continuously scanned over several degrees by varying the injection frequency.

Abstract: A printer having holographic scanning disc for scanning the imaging beam from a laser diode across a recording member, the diode having diode biasing and modulating current inputs for modulating the diode and thereby exposing and creating images on the recording member, a heating-cooling device in heat exchange relation with the diode for controlling diode temperatures, and a current sensor for monitoring the diode biasing and modulating currents and operating the heating-cooling device to adjust diode temperatures to maintain diode temperatures within a non-mode hopping temperature range.

Abstract: A printer having holographic scanning disc for scanning the imaging beam from a laser diode across a recording member, with a detector for detecting a shift in wavelength of the diode utilizing the zero order beam passing through the holographic scanning disc and a temperature control for controlling diode temperatures, the detector actuating the temperature control to adjust the temperature of the diode when a shift in the wavelength of the zero order beam from a non-mode hop wavelength to another wavelength is detected, adjustment of the diode temperature shifting the beam wavelength back toward the non-mode hop wavelength region.

Abstract: A lasing device includes heat-insulating members for individually surrounding support members associated with a semiconductor laser and a collimating lens assembly. Temperature control means is provided for controlling the support members to a predetermined temperature.

Abstract: A CO.sub.2 TEA laser utilizing an intra-cavity rotating prism Q-switch (70) for angularly switching the resonator gain by periodically causing the resonator mirrors (54, 56) to be in alignment. An opto-electronic timing device (79), which includes a graded index glass rod (76) rotating with the Q-switch prism, generates a pulse to initiate the laser discharge at the proper time before the mirrors are aligned so that the laser output pulse occurs when peak gain is achieved. The Q-switch speed of rotation is chosen such that the time interval in which the mirrors are aligned is not long enough to support the tail portion of the pulse typical of the gain switched CO.sub.2 TEA laser.

Abstract: In a CRT display device the target comprises a multilayered semiconductor including a p-n junction and at least one current-blocking layer. The e-beam is locally absorbed in the current-blocking layer so as to open a narrow zone which allows charge to flow through the forward biased p-n junction. The injection current produces a local spot of light which radiates from the opposite side of the device and whose position is varied by scanning the e-beam. In one embodiment the current-blocking layer is a semi-insulating semiconductor layer, and in another embodiment the current-blocking layer comprises the base of a normally cut-off transistor.

Abstract: A device is provided for fast frequency modulating the output spectrum of multimode lasers and single frequency lasers that are not actively stabilized. A piezoelectric transducer attached to a laser cavity mirror is driven in an unconventional manner to excite resonance vibration of the transducer to rapidly, cyclicly change the laser cavity length. The result is a cyclic sweeping of the output wavelength sufficient to fill the gaps in the laser output frequency spectrum. When such a laser is used to excite atoms or molecules, complete absorption line coverage is made possible.

Abstract: A portable, hand-held laser scanner system located within a compact housing. The housing includes a laser tube power supply means therefor and computer means. The laser is operative when triggered by the user to produce a laser beam which exits the housing to scan a target, such as a bar code symbol, located adjacent thereto and to receive light directed from the target. The computer is arranged for decoding the reflected signal. Communication means are provided within said housing to provide data output signals. The computer is arranged to control and override the operation of the laser when the amount of laser light produced within a predetermined period of time reaches a predetermined threshold value and for enabling the laser to operate when the amount of laser energy produced is less than the predetermined threshold value within the predetermined period of time.

Abstract: An aiming beam coincident with a laser beam is provided in a modified slit-lamp apparatus. The aiming beam is resolved into a number of images displaced with respect to the axis of the slit lamp imaging rays bracketing the intersection of the laser beam and the axis of slit lamp rays, which intersection is their common focus. As the common focus is moved close to a target tissue within the eye, the target tissue to be treated renders each of the images successively sharply visible while the other images remain blurry or not visible. Thus an efficient rough or long-range system is provided for focusing the laser on the target tissue.

Abstract: The invention involves the apparatus and the technique for non-invasive surgery to remove cataracted-lens tissue from an afflicted lens. The beam output of a laser is focused to a spot of maximum power density at the anterior surface of a cataracted lens and scanned over a predetermined area or areas of the cataracted lens. The beam is selective and safe since it's diffuse as it enters the eye through the cornea and is also diffuse (being divergent) in the unlikely event that the beam passes through an opening it has created in the cataracted lens. This diffusion assures against damage to either or both of the cornea and the retina. Focal power levels are used sufficient to achieve cataract material destruction thru ablative photodecomposition, thermal decomposition, photofragmentation, photoemulsification or any combination thereof. Various features are disclosed for assuring safety and uniformity in the removal of involved tissue.

Abstract: In an optical radar system a coherent signal is transmitted at a variable position and the return signal, that is, the reflected portion of the coherent signal is received and coherently detected. The transmitter utilizes a scanning laser having an electron beam that impinges upon a variable reflectance mirror that terminates one end of an optical cavity. An oscillating mode is generated within the resonant cavity when the electron beam locally heats the surface of the variable reflectance mirror to create a pixel that reflects light in a diffracted pattern. The receiver utilizes a stable single mode laser to illuminate a variable reflectance surface. A receiver electron beam generates a plurality of receiver pixels at various positions. The diffracted light from each pixel generates a plurality of variable angle local oscillator beams that are summed with the return signal at a beamsplitter. The output of the beamsplitter is applied to the surface of a detector array.

Abstract: The invention utilizes a laser cavity between two spherical mirrors, between which an oscillation wave propagates. An amplifying medium and an interaction medium are located on the path of the oscillation wave. A signal wave interferes with the oscillation wave in the interaction medium. A modulator of said wave makes it possible to initialize the process to obtain an output beam emerging in the desired direction.

Abstract: A method and apparatus for generating a plurality of secondary directional modes within the resonant cavity of a scanning laser oscillator. A first directional mode is generated by directing an electron beam on a variable reflectance end reflector to create a variable position pixel. A pattern of fixed reflectance material is positioned on the surface of the variable reflectance end reflector to generate the secondary directional modes within the resonant cavity. The oscillation threshold for the secondary directional modes is higher than the first directional mode, thereby allowing the first directional mode to have priority over the second directional modes. The second directional modes occupy the regions of the active laser medium of the resonant cavity not occupied by the first directional mode thereby suppressing the gain of the laser medium therein.

Abstract: A CO.sub.2 laser operating in the 10 .mu.m band is stabilized by a stabilization circuit that compares the power in a selected pair of R and P lines. A switching circuit connected into the stabilization circuit causes the laser's operating point to be switched within a short interval wherein four different pairs of R/P lines can be output within about 100 ms.

Abstract: A laser system for providing a rapidly steerable laser output beam. The laser system includes a phase conjugate reflector, laser gain medium and its associated pump source, an output coupling device, and an optical element which selectably controls the transverse lasing mode of the laser system. The components are arranged to form a laser oscillator between the phase conjugate reflector and the optical device, and is operated in such a manner that each selected transverse mode of laser operation generates an output beam from the system which has a different wavefront tilt. Accordingly, the output beam is steerable and is dependent upon the selected transverse mode which is currently lasing in the oscillator.

Abstract: A heterojunction-type laser is constructed with two closely spaced p-n junctions. Ohmic contacts are provided on both sides of the p-n junctions so that the voltages across the junctions can be individually controlled. By controlling the ratio of the voltages, the carrier distribution in the lasing active layer is controlled. This in turn controls the direction of the output beam of the laser in accordance with the ratio of the voltages, providing a laser beam which can be scanned without requiring mechanical means.

Abstract: A beam of coherent light is generated in a 360.degree. pattern about a central axis perpendicular to the beam, either outwardly from or inwardly toward the axis, without requiring moving parts. The beam is introduced into the space between concentric, cylindrical surfaces, both reflective to some extent, but one more highly reflective than the other, with respect to the wavelength of the beam. After multiple reflections between the surfaces, the beam passes through the less reflective surface about the entire 360.degree. circumference thereof. In a first embodiment the beam is generated by a conventional laser, or the like, and directed along an axis which perpendicularly intersects the axis of a hollow tube having external and internal surfaces which provide the aforementioned multiple reflections.

Abstract: A monolithic laser scanning device includes a semiconductor laser region integral with but spaced from an optical scanning region. These regions are optically coupled which may include a continuous transparent or passive waveguide medium. The periodic array of substantially parallel spaced electrodes are associated with the waveguide medium in the optical scanning region. The electrodes extend in the same direction as the propagating radiation in the medium. The voltages are applied in a pattern to the electrodes which voltages vary from one electrode to the next adjacent electrode to a predetermined value over several of the electrodes. The same pattern of voltages or a similar pattern of different voltages is applied over several of the next adjacent electrodes to the predetermined value until the pattern is completed across the electrode array to produce a corresponding approximation of a desired phase retardation along the phase front of the propagating radiation.

Abstract: Projection display devices and/or remote blackboard systems are provided with electrophoretic type cells used to control the projected light source. Light is directed toward the EPID cell through a total internal reflecting type prism, and reflected light from a totally internal reflecting surface at the interface of the cell and prism is projected to a viewing device. By writing information into the EPID type cell, total internal reflection can be frustrated and an image is formed at the viewing device. Information may be written into the EPID type device by a scaning laser, or by an electrostatic writing instrument.

Abstract: The optical beam scanner employs novel utilization of the well known Stark effect. By means of an external applied voltage, a change in the index of refraction of an optical medium is produced. This produces a bending effect on light transmitted through the medium. Varying the applied voltage can be used to vary the refractive index, or a refractive index gradient may be produced by providing a gradient in the applied field, to produce no moving parts scanning of the optical beam.