Laser sensor capable of measuring distance, velocity, and acceleration
First Claim
1. A sensor for determining a desired characteristic of an object, comprising:
- an oscillator producing a first signal;
a laser connected to said oscillator, said laser producing a laser signal;
a receiver for receiving a reflected laser signal from the object, and producing a second signal;
a conditioning circuit connected to said oscillator and said receiver for producing first and second conditioned signals, said conditioning circuit having first and second conditioning paths for said first and second signals respectively, said first and second conditioning paths having identical circuit elements, said conditioning paths further having identical path lengths;
a phase comparator connected to said conditioning circuit, said phase comparator creating a phase signal representative of a phase difference between said first and second conditioned signals; and
a processor connected to said phase comparator, said processor calculating distance to the object based on the phase signal.
1 Assignment
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Accused Products
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.
36 Citations
10 Claims
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1. A sensor for determining a desired characteristic of an object, comprising:
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an oscillator producing a first signal; a laser connected to said oscillator, said laser producing a laser signal; a receiver for receiving a reflected laser signal from the object, and producing a second signal; a conditioning circuit connected to said oscillator and said receiver for producing first and second conditioned signals, said conditioning circuit having first and second conditioning paths for said first and second signals respectively, said first and second conditioning paths having identical circuit elements, said conditioning paths further having identical path lengths; a phase comparator connected to said conditioning circuit, said phase comparator creating a phase signal representative of a phase difference between said first and second conditioned signals; and a processor connected to said phase comparator, said processor calculating distance to the object based on the phase signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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Specification