Abstract: An earthmoving apparatus and method for grading a tract of land to a desired finish contour wherein a continuously updated contour map is displayed to the operator of the earthmoving apparatus during the grading process is provided. The earthmoving apparatus has a blade of known width for cutting and filling soil of the tract of land. Vertical blade movement and the x and y position of the earthmoving apparatus is continually detected by respective sensors as the earthmoving apparatus traverses the tract of land. An ultrasonic transmitter and receiver detects elevation of the soil, preferably located behind the blade, to provide updated soil elevation information. A computer then uses the aforesaid information to generate a visual representation of a contour map of the tract of land with cut and fill lines thereon.

Abstract: A method and apparatus for holding an otherwise variable parameter in a scanner approximately constant over a desired scan volume to improve the ability to compensate for unwanted variations in the amplitude modulation depth of a signal is provided, the signal being determined from collected light reflected from a target. In one embodiment, the time domain impulse response of the opto-mechanical system is the parameter which is held approximately constant by appropriately positioning the beam waist so that the beam spot size diverges approximately linearly along the beam axis within the scan volume.

Abstract: Phase-locking means are provided for synchronizing the pulse timing of two (or more) passively mode-locked pulsed lasers. The phase-locking is carried out at a frequency much higher than that of the fundamental repetition rate of the lasers because it results in much higher sensitivity. The signal from the two bandpass filters is applied to a phase detector. A phase-locked loop circuit ("PLL") is employed to generate an error signal which is applied to a piezoelectric transducer ("PZT") attached to a mirror in one of the laser cavities. Corrections in the position of the mirror driven by the error signal help reduce the effects of phase noise in the relative fundamental repetition frequencies of the two lasers so that they are effectively synchronized with one another with a "jitter" of less than 1 ps.

Abstract: A synchronously pumped optical parametric oscillator (OPO) using a temperature-tuned 90.degree. phase matched LBO crystal is disclosed which provides a broad selection of output wavelengths. A Ti:Sapphire pump source having a cavity length matched to the OPO cavity length pumps a cavity with an LBO crystal located at the cavity waist of the cavity mode.

Abstract: A high output, compact laser having a multi-line spectral output and an internal mirror, integral resonator design is disclosed. The laser structure comprises a laser tube containing a resonant cavity, an output coupler and an active medium. A power supply and coolant assembly are coupled to the laser tube. The coolant assembly is a hybrid coolant scheme wherein one portion of the tube is cooled by circulating water coolant, while another portion or portions are cooled by circulating air. In one aspect, the laser tube includes a ceramic bore surrounded by a sheath sealed at a first end and a second end of the ceramic bore, and coolant is provided between the sheath and the bore. In a further aspect, forced air is directed over a reservoir portion of the tube. The reservoir portion may be manufactured from a metallic alloy comprised of nickel iron cobalt with copper cooling fins brazed to the reservoir to increase thermal cooling efficiency and isothermal distribution of heat.

Abstract: A Fourier Transform Raman Spectrometer system includes a folded V laser cavity. A first leg of the folded V laser cavity is defined by a highly reflective end mirror and a dichroic fold mirror and a second leg of the folded V laser cavity is defined by the fold mirror and an output coupler. A solid-state laser gain medium is disposed in the first leg of the folded V laser cavity and is pumped by a pump source aligned with the optical path of the first leg of the laser cavity and radiating through the fold mirror. The fold mirror is highly transmissive at the wavelength of pump radiation from the pump source and highly reflective at the laser output wavelength. An output beam from the laser is passed through a tuneable filter comprising an acousto-optic device and is directed at a sample to be analyzed. Light reflected from the sample is directed to a Raman Spectrometer for analysis.

Abstract: An interface selection and configuration system for a computer peripheral in which configuration for the peripheral and/or the host interface is at least in part accomplished by the interface connector cable. In a preferred embodiment, the computer peripheral is equipped with one or more hardware interfaces. The interface connector cable has a first end connector for attaching to the computer peripheral. The first end connector of the interface connector cable is typically a multiple pin connector constructed and arranged to be properly physically and electrically connectable only to a specific computer peripheral or class of computer peripherals, the first end connector including at least one electrical connection between two pins for completing a circuit within the computer peripheral thereby enabling the computer peripheral.

Abstract: An optical system and method for data reading in which a light source generates an optical beam directed toward an object to be read and a variable aperture mechanism positioned in the outgoing light path establishes at least two separate focal planes. The variable aperture device may comprise a variable aperture system in which the size of the aperture is selectively varied about a range within the diffractive limit of the light beam. A preferred aperture mechanism is an LCD aperture with one or more aperture regions which are selectively or consecutively activated. The optical system therefore establishes two or more separate focal planes from a single light source resulting in greater depth of field or multiple depths of field.

Abstract: An assembly for use in a laser instrument which produces a plane of laser light by reflection from a cone. The assembly includes a weak focusing lens which improves the control over the planarity of the plane of light produced. Because it is weak, the weak focusing lens can be positioned over a relatively large distance to produce slight changes in the focus of the beam which is reflected to produce the plane of light. Critical, time consuming, and expensive manufacturing requirements can be relaxed, while improved performance results in superior laser instruments.

Abstract: An aircraft control system for applying chemicals to an agricultural field in one of a plurality of flight patterns is provided. A global positioning system receiver receives radio frequency signals from satellites and the position of the aircraft is determined from the information contained in the received signals. An aircraft computer stores the surface coordinates of the field to be sprayed. The aircraft pilot enters the desired orientation, swath width and track width of the flight pattern into the computer. Based on the aforementioned information, the computer produces a flight pattern having the desired orientation and generates, via a pilot headset, audible signals representative of amount and direction of deviation from the desired flight pattern. The computer means may also automatically activate and deactivate chemical spraying upon entering and exiting, respectfully, the airspace above the field.

Abstract: An interface selection and configuration system for a computer peripheral in which configuration for the peripheral is at least in part accomplished by the interface connector cable. In a preferred embodiment, the computer peripheral is equipped with one or more hardware interfaces. The interface connector cable has a first end connector for attaching to the computer peripheral. The first end connector of the interface connector cable is typically a multiple pin connector constructed and arranged to be properly physically and electrically connectable only to a specific computer peripheral or class of computer peripherals, the first end connector including at least one electrical connection between two pins for completing a circuit within the computer peripheral thereby enabling the computer peripheral.

Abstract: Two resonant cantilever beams oscillate in a sinusoidal pattern. Mirrors disposed on the oscillating ends of the cantilever beams are used to multiplex two scanning and collecting light beams. The cantilever beam parameters and mirror configuration are selected so that the scanning light beam is on the first mirror during the linear portion of its scan. As the first cantilever beam oscillates out of the linear portion of the sine wave, the deflection of the first mirror is just great enough to allow the scanning beam to strike the second mirror during the linear portion of the second mirror's scan. The process is repeated twice each cycle. The collection lens is large enough to receive the full aperture of both mirrors at all times. Multiplexing of scanning diodes is also accomplished by a controller circuit which alternately enables diodes disposed on the ends of respective first and second cantilever beams during the linear portion of each sine wave oscillation.

Abstract: A laser source arrangement is provided for use in a laser instrument of a kind used to transmit a scan pattern to a target which is spaced from the laser instrument and to detect light reflected from the target. The laser source arrangement preferably comprises a laser diode for producing a laser beam used to form the scan pattern. The laser diode is characterized by astigmatism which is subject to variation with the temperature of the case of the diode. The arrangement further includes drive apparatus for driving the laser diode in a pulsed mode having a duty cycle which reduces the astigmatism and substantially controls the temperature dependence of the astigmatism. Optics are also provided for statically correcting the astigmatism of the laser diode.

Abstract: An actuator for controlling alignment of an object that is characterized by an alignment plane, such as mirrors used in optical cavities, comprises a mounting frame, and a one piece alignment member formed of piezoelectric material having a first end and a second end that is secured to the mounting frame at the second end. On the first end, a first object contact, a second object contact, and a third object contact are secured defining an object plane. A means is provided for holding the object in contact with the first, second and third object contacts so that the alignment plane of the object has a predetermined relationship with the object plane defined by the object contacts on the tubular member. Electrodes are formed on the tubular member for establishing an electrical field between the surfaces of the alignment member so that the positions of the first object contact, second object contact and third object contact are controlled.

Abstract: A method for affixing the optics of a laser to the laser tube, comprising: providing a substrate seat, coupling a substrate to the seat, coating the substrate with a multilayer thin film coating, and securing the substrate seat to the laser tube. In a further aspect, a method for manufacturing a resonant cavity is disclosed, the method comprising: providing a laser tube having first and second ends, securing a substrate mount, having a coated output coupler secured thereto, into one end of the laser tube, securing a substrate mount, having a coated reflecting mirror secured thereto, into the other end of the laser tube, and sealing the laser tube.

Abstract: A method and an apparatus facilitate scanning an Add-On code portion of a bar code label to determine the bar code data printed thereon by sweeping a scanning beam in a scan path across the Add-On code portion of the label. The bar code label includes bar codes of the type which have a primary code portion and which may also have an Add-On code portion.

Abstract: A method and system for determining the position of at least one position retroreflective element in a predetermined frame of reference using two benchmark positions of known coordinates. A light transmitting and detecting means and a reference retroreflective element are oppositely positioned at a primary benchmark position located at known first coordinates and a secondary benchmark position located at known second coordinates. The light transmitting and detecting means takes angular measurements by sensing a reflected light beam from the position and reference retroreflective elements. After taking angular measurements in the above configuration, the light transmitting and detecting means and the reference retroreflective element are transposed and additional angular measurements are taken. From the angular measurements, the position of the position retroreflective element is determined in the coordinate frame of reference.