Spectra-physics Laserplane, Inc.

Spectra-physics Gmbh

Mark D Sobottke

Daniel R Klemer

Gary Lynn Cain

Ted L Teach

Pliny S Hawthorn

Jamie N Lussier

Joseph F Rando

James Thomas Zalusky

Theodore J Markley

William K Vatter

Gerald H Church

Richard J Omlor

An active etalon comprising a laser gain chip interposed between an input mirror and an etalon end mirror is provided. In an intracavity frequency-doubled solid-state laser, a pump source emits pump radiation which passes through the input mirror and into the laser gain chip. The laser gain chip lases in response to the pump radiation to produce fundamental laser light. The etalon end mirror reflects a portion of the fundamental laser light back into the laser gain chip and transmits the remaining portion of the fundamental laser light into the laser cavity. The input mirror reflects substantially all of the fundamental laser light into the laser gain chip. The portion of the fundamental laser light which passes through the etalon end mirror may be frequency doubled by a frequency doubler chip and a portion thereof transmitted through the front end of the laser cavity to form the output laser beam.

Solid-state laser with active etalon and method therefor

A pipe alignment system and method is provided for positioning a pipe line along a predetermined path. A light transmitter generates a reference light beam along which the pipe line is to be positioned. The light beam has wavelengths substantially in the green portion of the optical spectrum. An optical target is positioned at one end of each pipe section to assist in alignment thereof. Preferably, the optical target has a green tint which filters the green light from ambient light. The optical target may also have reference indicia thereon to assist in aligning the target with the reference beam of light.

Pipe alignment apparatus and method using green light

A solid-state laser comprises a pump diode for generating pump radiation and transmitting the pump radiation into a laser cavity. The pump radiation passes through an entrance mirror and enters a laser gain chip which lases to produce fundamental laser light. The fundamental laser light passes through a harmonic reflector and a first dispersive element and is frequency doubled by a frequency doubler chip to produce harmonic laser light. The harmonic laser light passes through a second dispersive element and impinges on a mirrored surface. A portion of the harmonic laser light passes through the mirrored surface to form the output beam of the laser. The remaining portion of the harmonic laser light is reflected back into the laser cavity. First and second dispersive elements control the phase of the harmonic laser light in the laser cavity such that substantially all of the harmonic laser light is in-phase when the harmonic laser light impinges upon the mirrored surface.

Efficient linear frequency doubled solid-state laser

A solid-state laser for generating harmonic laser light substantially at a desired wavelength has a pump diode body made of a first material, which is preferably aluminum, having a first coefficient of expansion and a laser diode mounted in the pump diode body for generating pump energy. A laser body assembly, which is positioned on the pump diode body, is made of a second material, which is preferably steel, having a second coefficient of expansion. The first and second coefficients of expansion of the respective pump diode body and the laser body assembly have a known relationship such that the laser cavity expands and contracts at a particular rate as the temperature of the laser increases and decreases to provide a substantially constant generation of the harmonic laser light. A laser gain chip mounted on an entrance mirror, which forms the back end of a laser cavity, generates fundamental laser light in response to pump energy from the laser diode. The fundamental laser light passes through an active etalon output mirror into a frequency doubler chip which doubles the frequency thereof to produce harmonic laser light. A mirrored surface, which forms a front end of the laser cavity, permits a portion of the harmonic laser light to be emitted from the laser and reflects the remaining portion of the harmonic laser light back to the active etalon output mirror. A control etalon may be provided to suppress undesired light wavelengths in the laser cavity.

Solid-state laser

An intracavity frequency-doubled solid-state laser uses a Nd:GdVO.sub.4 laser gain chip to generate a beam of visible laser light which may have wavelengths substantially in the green portion of the optical spectrum. A back end of the laser cavity is defined by an entrance mirror while a front end of the laser cavity is defined by a mirrored surface. A laser diode generates pump light which is transmitted through the entrance mirror into the laser gain chip. The laser gain chip, which may be immediately adjacent the entrance mirror, emits fundamental laser light having a wavelength of approximately 1063 nm in response to the pump light. A frequency doubler chip positioned immediately adjacent the laser gain chip doubles the frequency of the fundamental laser light to produce harmonic laser light having a wavelength of substantially 532 nm. In a second embodiment, the frequency doubler chip is immediately adjacent to the entrance mirror and the laser gain chip is immediately adjacent to the frequency doubler chip. The mirrored surface reflects a portion of the harmonic laser light back into the laser cavity and transmits a portion of the harmonic laser light from the laser.

Gadolinium vanadate laser

A laser beam target for use with a projector capable of providing a reference laser beam of light traveling in a predetermined path is provided and includes a main body portion having first and second surfaces. A plurality of projections are provided on at least one of the first and second surfaces for directing at least a portion of the reference beam of light into a specific range of vertical viewing angles away from the path of the beam as the light passes from the body, thereby permitting a worker viewing the target to more easily determine when the reference beam of light is in alignment with appropriate reference indicia on the target.

Laser beam target

Apparatus operable in accordance with the method of the present invention for measuring the angle of incidence of a light beam or plane relative to level comprises a photodetector array for sensing the light and a level mirror preferably comprising a pool of mercury. Optics are provided for transmitting the light to the photodetector array in alignment with the angle of incidence of the light (aligned light) and also after the light has been reflected from the mercury pool (reflected light). A shutter is provided for separating aligned light from reflected light such that distinct signals representative of the two are generated by the photodetector array. The distinct signals are processed by up-counting and down-counting a counter circuit to determine the average centers of light spots representative of the aligned light and the reflected light and the distance between those average centers which is representative of the deviation of the light beam or plane from level.

Method and apparatus for measuring incident light angle relative to level

A laser beam three dimensional position measurement system includes a laser transmitter mounted at a stationary reference position at a work site and a receiver mounted on a mobile machine at the site. The transmitter produces a laser reference plane by sweeping a laser beam about the transmitter. The receiver includes a retroreflector which intercepts and reflects laser energy back to the transmitter when the laser beam sweeps past the retroreflector. The system also includes at the transmitter a circuit composed of a photodetector, timer, clock and counter. The photodetector senses laser energy reflected back to the transmitter from the retroreflector. The timer modulates the laser beam produced by the transmitter in response to detection of the beam. The counter is connected to the clock and timer, and is enabled by the timer to start counting electrical pulses received from the clock when the beam is modulated. The counter is disabled to stop counting electrical pulses when the modulation is detected. The number of pulses counted by the counter is indicative of the range of the receiver from the transmitter. The orientation of the beam relative to a fixed reference axis at the time reflected laser energy is detected defines the direction of the receiver relative to the transmitter.

Laser-based measurement system

A compact, laser diode pumped, high efficiency, solid-state laser comprises an output coupler mirror forming a front end of a laser cavity. A back end of the laser cavity is formed by a rear mirror through which emissions from a laser diode pass for pumping a laser chip of stoichiometric lasing material. A frequency doubler chip is positioned immediately adjacent the laser chip to double the frequency of light generated by the laser chip and thereby halve its wavelength. The laser chip is bonded to the frequency doubler chip by coupling material having a refractive index matched to the chips to nearly eliminate reflections at the bonded chip surfaces. Such bonding increases the effective Q of the laser cavity which receives the bonded combination of the laser chip and the doubler chip at a beam waist defined within the laser cavity by means of beam shaping with the laser chip being positioned to receive pumping energy from a laser diode through the rear mirror of the laser cavity. Spiking or peaking of the output laser light is effected by gain switching, phase modulation or by imparting vibratory motion to the bonded combination of the laser chip and the frequency doubler chip.

Low cost/power visible light solid-state laser

Apparatus for projecting a laser beam to provide simultaneously a stationary reference beam and a moving reference beam, which rotates in a plane normal to the stationary reference beam, includes a beam diverting arrangement for intercepting a primary beam and for splitting the beam into the two reference beams. The beam diverting arrangement includes first and second deflecting elements which deflect the beam by 90.degree. with respect to the primary beam. A portion of the primary beam, striking the first deflecting element, passes through the element and is shifted slightly by refraction. This shift is compensated by a third beam deflecting element which is fully transmissive, and which refracts the stationary reference beam into alignment with the primary beam. By cutting the first and third deflection elements from the same sheet of material and reorienting the elements appropriately, slight deviation from parallelism in the opposing surfaces of the sheet of material are compensated.

Multiple reference laser beam apparatus

An apparatus for projecting a laser beam in a reference plane includes several imrovements. A generally cylindrical, one-piece molded transparent lighthouse structure overlies the rotatable pentaprism beam diverting assembly of the apparatus. The lighthouse structure is mounted on the housing so as to allow transmission therethrough of the rotating laser beam projected by the beam diverting assembly. The lighthouse structure has a tapered or conical configuration facilitating molding thereof, but which produces a divergence of the laser beam as it passes through the structure. A continuous resilient flexible ring is adapted to releasably attach to the apparatus housing and tightly fit about the lighthouse structure for removably anchoring the structure to the housing in a sealed relationship, providing a water-tight enclosure for the pentaprism beam diverting assembly and imposing a generally uniform attaching pressure about the lighthouse structure. A beam compensating lens aligned across the laser beam and coupled with the beam diverting assembly for movement therewith. The compensating lens being in the form of a positive meniscus lens is configured to correct the divergence in the laser beam which occurs when the beam passes through the one-piece molded lighthouse structure.

Growing community of inventors

Kettering, OH, United States of America

Mark D Sobottke