Abstract:
PROBLEM TO BE SOLVED: To measure the distance to the object to be measured and the speed of the object while taking advantage of the laser measurement device of a self adopted type. SOLUTION: The distance/speed meter comprises: the semiconductor laser 1; the laser driver 4 making repetitions alternatively the first oscillation interval in which the oscillation wave length is continuously increased and the second oscillation interval in which the oscillation wave length is continuously decreased in the semiconductor laser 1; the photo diode 2 for converting the optical output of the semiconductor laser 1 into the electric signal; the counting means 5-8 for counting the number of pulses based on the interference between the optical output of the semiconductor laser 1 and the return light from the object 11 included in the output of the photo diode 2 in the semiconductor laser 1 for each of the first oscillation interval and for the second oscillation interval; and the operation means 9 for calculating the distance to the object 11 and the speed of the object 11 from minimum oscillation wave length and the maximum oscillation wave length of the semiconductor laser 1 and the count results of the counting means. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
A light based distance, velocity and acceleration sensor which uses phase difference to determine the desired measurement. A laser signal is modulated by an oscillator signal and reflected off an object to a signal receiver. The reflected laser signal and the oscillator signal then pass through a dual path conditioning circuit, where the path lengths and circuit elements of the two paths are identical to cancel the effects of propagation delays in an output signal. The conditioned signals are passed through a phase comparator, to produce a signal indicative of the phase difference between the oscillator signal and the reflected laser signal. The phase difference is directly proportional to the distance between the sensor and the object.
Abstract:
PROBLEM TO BE SOLVED: To enhance precision and reliability in distance determination. SOLUTION: A measuring section has delay sections. The plurality of delay sections is provided in the measuring section, and one of the delay sections is connection-switchable to the measuring section. Alternatively, the plurality of delay sections is provided in a reference section, and one of the delay sections is connection-switchable to the reference section. COPYRIGHT: (C)2005,JPO&NCIPI
Abstract:
In a method and a device for carrying frequency synthesis, in particular in a distance measuring device based on the principle of evaluating the change over time in the phase of an electromagnetic radiation emitted by a radiation source and remitted by an object aimed at, a frequency, which is preferably furnished by a quartz oscillator, is regulated in a ring oscillator with N delay elements (V1, V2, V3, . . . , VN) to a desired first high frequency (F), which is used as a mixer frequency or as a modulation frequency. The signals at the N delay elements (V1, V2, V3, . . . , VN) are delivered to a multiplexer, which is switched over with a cadence that is equivalent to 2*N times the frequency of the low-frequency measurement signal to be evaluated to produce a modulation frequency or mixer frequency.