Title:
LASER RANGE FINDER
Document Type and Number:
Japanese Patent JP2500733
Kind Code:
B2
Abstract:
PURPOSE: To detect light reception time accurately and to achieve a highly accurate range finding even if the light reception signal level fluctuates due to the difference in the reflection factor of a target in a range finder in pulse laser system.
CONSTITUTION: The range finder for measuring the distance to a target based on the reflection time of laser beams by a counter display 30, having a light transmission part 10 for projecting pulsive laser beams to a target O and a light reflection part 20 for receiving the reflection light from the target O, is provided with a light detector 22 for detecting the received laser beams as electrical signals, a logarithmic amplifier 23 for amplifying the detection output logarithmically, a delay element 24 for delaying the amplified output partially, a peak-hold circuit 26 for retaining the peak value of the other one part of the amplified output, a level shifter 27 for obtaining a voltage which is lower than the peak value by a constant voltage, and then a comparator 25 for comparing the output of the delay element 24 with that of the level shifter 27 and then outputting the time signal when receiving light, thus achieving an accurate range finding regardless of the level fluctuation of the light reception signal.
Inventors:
HARADA TETSUO
Application Number:
JP1439993A
Publication Date:
May 29, 1996
Filing Date:
January 04, 1993
Export Citation:
Assignee:
NIPPON ELECTRIC CO
International Classes:
G01S17/10; (IPC1-7): G01S17/10
Domestic Patent References:
| JP6160523A |
Attorney, Agent or Firm:
Suzuki Akio