摘要:
Error introduced by analog to digital conversion of a set of laser pulses can be reduced by shifting the clock reference time associated with the firing of the laser pulse. A timing offset module shifts the timing reference of each laser pulse. Digital codes generated by the ADC from the received signals are realigned and summed eliminating systematic error introduced by clock driven operations of the ADC. A comparison of the total ADC output of detected laser pulses over a select number of clock intervals enables a return signal to be distinguishable over the systematic error.
摘要:
A high precision, high performance optical system and beam pathway design for laser-based distance measuring, or range-finding, devices includes an etched, or etched and filled, aiming reticle in the image plane which does not require daytime use illumination, and only minimal auxiliary illumination during nighttime operation, thereby conserving available battery power. In a preferred embodiment, a low power consuming back-lit liquid crystal display provides high contrast distance or other operational information to a user superimposed upon a black-appearing field stop thereby further providing operational power savings.
摘要:
A laser rangefinder bow sight adapted for use preferably with a conventional multi-pin bow sight having a frame and a plurality of sighting pins adjustably positioned on said frame. The laser rangefinder has a housing removably fastened to the bow sight frame. The housing supports a laser transmit section, a laser receive section, a precision timing section and a central processing unit (CPU) for measuring distance to a target coupled to an LCD display. The CPU also provides outputs to a plurality of range window indicator lights which are preferably LEDs. The indicator lights may be externally mounted to the bow sight pins or mounted within the rangefinder housing. In the latter case, a plurality of optical fibers are connected to the distance window lights in the housing. Each of the sighting pins is optically coupled to a separate one of the plurality of distance window lights via one of the optical fibers. The rangefinder is actuated via a remote trigger switch connected through the power supply in the housing to each of the sections. When the rangefinder is triggered, the CPU determines the target distance and activates one or more of the distance window LEDs for the range window or windows closest to the measured distance. Light is then transmitted via the optical fibers to the sighting pins, thus illuminating the one or two sighting pins corresponding to the measured distance. The display is held for a predetermined period of time or until the archer actuates the remote switch to take another distance measurement.
摘要:
A circuit and apparatus for generating a light pulse from an inexpensive light-emitting diode (LED) for an accurate distance measurement and ranging instrument comprises an LED and a firing circuit. An optional pre-biasing circuit provides a reverse-bias signal to the LED to ensure the LED does not begin to emit light before a firing circuit can provide a sufficiently high current pulse of short duration as a forward current through the LED. The LED is driven by the firing circuit with a pulse of high peak power and short duration. The resulting light pulse from the LED can be inexpensively used to derive distance and ranging information for use in a distance measurement and ranging device.
摘要:
An apparatus is disclosed for determining, in a first speed mode of operation, speed and range of a moving object and, in a second survey mode of operation, determining direct distances to an object and automatically calculate horizontal and vertical component distances to the object. Also disclosed is a system and method for data entry and retroactive reconstruction of the relative position of features and objects, in particular with respect to scenes such as transitory occurrences, utilizing a signal transmitting and receiving speed, distance and tilt angle determining apparatus or device. In a particular embodiment, the apparatus disclosed has especial applicability to tactical situation use by law enforcement personnel and the system and method in the on-scene recordation and subsequent ex post facto reconstruction of crime and traffic accident scenes by law enforcement officers. The system and method may be readily and efficiently implemented in conjunction with a laser-based speed, distance and tilt angle determining device otherwise usable for vehicle speed traffic monitoring functions utilizing either triangulation or baseline/offset mensuration techniques.
摘要:
An apparatus and method for accurately determining a target distance in adverse weather conditions utilizing both LASER and RADAR is disclosed. The radar signals are used to determine an approximate range which is then used as a gating window for the determination of which laser reflection is from the actual target as opposed to a reflection from the atmospheric interference. The method basically comprises the steps of initiating a radar pulse in the direction of a target and receiving a reflection, transmitting a laser signal and receiving a plurality of reflections, determining an approximate range based on the radar signals, and using this approximate range to ascertain which of the laser reflections is from the target. This determination is preferably made by generating a gating signal and gate width from the radar signals and passing the set of laser range signals through the gate to eliminate the false signals and select the signal that survives the gate as the accurate target range.
摘要:
A voltage conversion circuit for transforming an input voltage level at an input voltage node to a relatively higher output voltage level at an output voltage node with respect to a common reference voltage node includes an inductor coupling the input voltage node to the output voltage node and a signal source, such as a linear timer integrated circuit ("IC") supplying an output signal having alternating first and second states thereof. A bipolar switch having first and second current carrying terminals and a control terminal thereof has its first current carrying terminal coupled to the output voltage node and its control terminal coupled to receive the output signal from the signal source. An MOS switch having first and second voltage carrying terminals and a gate terminal thereof, has its first voltage carrying terminal coupled to the common reference voltage node, its second voltage carrying terminal coupled to the second current carrying terminal of the bipolar switch and its gate terminal coupled to receive the output signal from the signal source. At least one diode couples the control terminal of the bipolar switch to the reference voltage node.
摘要:
A system and method for data entry and retroactive reconstruction of the relative position of features and objects, in particular with respect to scenes such as transitory occurrences, utilizing a signal transmitting and receiving distance determining device. In a particular embodiment, the system and method disclosed has especial applicability to the on-scene recordation and subsequent ex post facto reconstruction of traffic accident scenes by law enforcement officers and may be readily and efficiently implemented in conjunction with a commercially available laser-based speed and distance determining device otherwise usable for vehicle speed traffic monitoring functions utilizing either triangulation or baseline/offset mensuration techniques.
摘要:
An automatic noise threshold circuit and method automatically sets an operating threshold for a signal receiving section of a laser pulse transmitting device such that a constant noise pulse firing rate is output from a detector to provide maximum return signal sensitivity and enable detection of the weakest possible laser pulse in order to obtain maximum performance out of a laser range finder. The circuit sets the noise pulse rate at that point at which, in conjunction with a firmware based process, the actual return signals from the target can be discrimintated from the accompanying noise.
摘要:
A method of ablating non-metallic dental material from a tooth comprises the steps of generating radiation pulses having a predetermined wavelength, energy level, pulse repetition rate, and duration, and applying the radiation pulses to the non-metallic dental material in a tooth, whereby the non-metallic dental material is ablated from the tooth. The radiation may be generated by a frequency tripled Nd:YAG, an Er:YAG laser or an Er:YsGG laser and may have a wavelength of about 355 nanometers, 2.94 micrometers, and 2.79 micrometers respectively, for example.