Abstract: In an external mirror type semiconductor laser composed of a semiconductor laser having a structure wherein a reflection factor is reduced on one end plane thereof, and a lens as well as a grating type reflector disposed on the side of the end plane, respectively, the lens is shifted in the direction orthogonal to a light axis, and an incident angle of the light outputted from the end plane to the grating type reflector is changed, whereby an external mirror type wavelength tunable laser having a simple structure and tuning a radiated wavelength can be realized.

Abstract: An integrated electro-optical package including a laser diode microscanner, and an automatic focus mechanism housed within a housing. The microscanner includes a semiconductor wafer, having formed as a part thereof a cantilevered portion having mounted thereon at least one laser diode. The cantilevered portion having electrically interfaced thereto a plurality of interconnects capable of delivering varying voltages. The cantilevered portion is deflected in response to the varying voltages and therefore produces a scanning action in an "x" and/or "y" direction dependent upon the external varying voltage applied thereto and the design of the cantilevered portion. The automatic focus mechanism includes a single detector or a detector array that measures a reflected light and submits a signal to the display system optics for focus adjustment dependent upon the measurements received.

Abstract: An exemplary laser apparatus comprises an amplification medium which amplifies a coherent beam passing through the amplification medium, a pump which provides energy to the amplification medium, a tunnel having a first end proximate to the pump and a second end proximate to the amplification medium, wherein the energy provided by the pump passes through the tunnel en route to the amplification medium, and a moveable member for adjusting a spatial distribution of the energy provided to the amplification medium by the pump. The moveable member typically comprises a flat, reflecting strip or flap which redirects a portion of the energy of the pump beam to a peripheral region of the amplification medium. The angular and translational position of the flap is adjustable on line so that the pump distribution can be adjusted while the laser is running to reduce observed optical distortions caused by heating of the amplification medium.

Abstract: The invention relates to a microlaser cavity, with active Q switching, characterized in that it comprises:an active laser medium (20), an input mirror (22) and an output mirror (24, 87) defining the cavity,a micromodulator with frustrated total internal reflection, comprising two microprisms (32, 34) made of a certain material of index n.sub.1 each having at least one planar face (36, 38), the two planar faces being approximately parallel to each other and inclined on the microlaser cavity axis, thereby defining a plate (30) of a certain material of index n.sub.2 less than n.sub.1.means (44, 46, 48, 50, 52, 54) for varying the thickness of the plate.

Abstract: A wavelength-conversion solid-state laser capable of generating a ultraviolet laser beam with high efficiency. The wavelength-conversion solid-state laser is made up of a phonon-based solid-state laser crystal, a semiconductor laser which emanates pump light to pump the phonon-based solid-state laser crystal, a laser resonator, a wavelength selection element which selects an oscillation wavelength, and a nonlinear optical crystal which generates a sum frequency of a solid-state laser beam, whose wavelength is selected by the wavelength-selection element, and the pump light. The phonon-based solid-state laser crystal is pumped with pump light emitted from the semiconductor laser, as a result of which a solid-state laser beam is emitted. A sum frequency of the solid-state laser beam and the pump beam is produced by enabling them to pass through the nonlinear optical crystal.

Abstract: A laser comprises an upconversion laser gain element made of a crystalline xide host doped with activator ions for emitting output radiation at an output wavelength. The gain element is pumped by pumping radiation at a pumping wavelength that is longer than the output wavelength. A laser resonator comprising a reflective element and an output coupler is arranged with the gain element to resonate the output radiation. The reflective element is spaced from the output coupler by a distance approaching the radius of curvature of the reflective element or the output coupler. The pumping radiation has a waist that is substantially coincident with the waist of the output radiation within the active region of the gain element.

Abstract: A shutter mechanism having a slide element coupled to a support base by a plurality of roller bearings journaled between opposing pairs of guide rods is disclosed. The slide element and support base have corresponding beam apertures in alignment when the shutter is in its open position. Angularly mounted on the slide, adjacent to the slide's beam aperture, is a UV reflective mirror. When the shutter is commended to close, an actuator forces the slide and support base apertures out of alignment, while simultaneously positioning the UV reflective mirror into the position previously occupied by the slide's aperture. A laser beam, previously being transmitted through the aligned apertures, will be reflected by the mirror to a beam stop as a diagnostic instrument mounted on the support base.

Abstract: A laser is end pumped by laser diodes and is repetitively Q-switched using an intracavity variable speed moving aperture. The aperture apparatus includes a precision motor which drives a pair of matched aperture blades and produces efficient Q-switched operation over a wide range of output powers and repetition rates. Each aperture blade may contain an identical number of transmissive and opaque regions, and two aperture blades may be mounted onto the motor in a manner that allows continuous adjustment of the aperture width. In a preferred embodiment the aperture blades are shaped as circular discs. The laser resonator mode is nearly hemispherical, and the aperture blade is located at or near the laser resonator mode waist. When pumped with the optimum pump flux, efficient repetitively Q-switched operation is obtained as long as the Q-switch opening time is shorter than the pulse build-up time.

Abstract: A length of an optical fiber having a core and a surrounding cladding is held by a block with a portion of said length having substantially all of its cladding removed on one side of the portion and being exposed, and an index overlay perturbation pad is mounted near and substantially parallel to the portion. A translator moves the pad between a first position in which the pad is sufficiently remote from the portion to allow total internal reflection in the portion and a second position in which the pad is sufficiently close to the portion to allow light to escape from the core. The pad may be made of a metal for polarized modulation, or of a dielectric for unpolarized modulation. The optical switch provides very fast switching for a O-switched fiber laser.

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: The optical cavity of the present laser has a folded optical path with a pair of reflective diffraction gratings and a gain cell in it. A disk with radially distributed perforations rotates in the optical path between the gratings and the gain cell. The laser wavelength depends upon which perforation is aligned with the slot in a slotted plate also in the optical path. The laser output consists of a sequence of different wavelength but colinear rays.

Abstract: A laser apparatus includes an operating laser oscillator for generating an operating laser beam for medical treatment and a marker laser oscillator for generating a visible laser beam (i.e., marker laser beam) in order to mark a portion of the body cavity to be treated. The marker laser beam is guided coaxial with the operating laser beam to become incident on a laser probe. The marker laser beam is intermittently shielded by a chopper. The shielded marker laser beam is reflected by a reflecting surface of the chopper and is guided to a photosensor. The operating laser oscillator is driven in response to an output signal from the photosensor.