Title:
【発明の名称】光ビーム距離計
Document Type and Number:
Japanese Patent JPH11506825
Kind Code:
A
Abstract:
A "laser tape measure" for measuring distance which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%.
Inventors:
McKee One, Thomas, Yi.
Application Number:
JP50068597A
Publication Date:
June 15, 1999
Filing Date:
May 22, 1996
Export Citation:
Assignee:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
International Classes:
G01B11/00; G01C3/08; G01F23/284; G01S1/04; G01S5/14; G01S7/282; G01S7/285; G01S11/02; G01S13/02; G01S13/04; G01S13/18; G01S17/10; G01S19/19; G01S19/44; G01S19/46; G01V3/12; G08G1/04; H01Q1/22; H01Q9/30; H01Q19/10; G01S7/481; G01S13/00; G01S13/10; G01S13/88; (IPC1-7): G01S17/10; G01B11/00
Attorney, Agent or Firm:
Yasuo Ishikawa