Title:
【発明の名称】パルス方式の光波距離計
Document Type and Number:
Japanese Patent JP2896782
Kind Code:
B2
Abstract:
A light wave distance measuring instrument uses a light receiving diode for receiving both light from a light source diode coupled via an internal light passage and light from the light source diode coupled via an external light passage. A beam splitter separates light pulses from a single source diode to supply light pulses for both internal and external passages. A reference signal is sampled using detected signals representing the timing of received internal reference light pulses and external measurement light pulses to provide first and second signals with phase difference representing measured distance. These signals are processed in a CPU for calculating distance with reduced errors due to frequency drift. By introducing an optical fiber delay medium, reflected light pulses are separated in time from the internal reference pulses so that these pulses can be used directly for differential time determination purposes and the measurement of distances to objects close to the measuring instrument is made possible.
Inventors:
OOISHI MASAHIRO
OOTOMO FUMIO
OOTOMO FUMIO
Application Number:
JP33528288A
Publication Date:
May 31, 1999
Filing Date:
December 30, 1988
Export Citation:
Assignee:
TOPUKON KK
International Classes:
G01S7/48; G01B11/02; G01S7/481; G01S17/14; (IPC1-7): G01S17/10; G01S7/48
Domestic Patent References:
| JP5960271A | ||||
| JP5712379A | ||||
| JP6385489A | ||||
| JP6263885A | ||||
| JP6321877B2 |
Attorney, Agent or Firm:
Yuichi Izumi