Title:
レーザ干渉変位計
Document Type and Number:
Japanese Patent JP3552386
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To measure the precise displacement without being affected by the disturbance in the waveform of beat signals by judging the positive and negative nature of data obtained by sampling one cycle of a beat signal at a constant sampling cycle and encoding the results. SOLUTION: Light beams radiated from a laser diode 101 are irradiated through a collimator lens 102, a beam splitter 104, and a rod lens 106 to an object 107 to be processed and the reflected light beams generate a beat signal by heterodyne interference. Following a timing signal of a timing controller 201, a data sampler 203 carries out sampling by an output signal of a BPF 202 and transfers to a decoder 204. The decoder 204 judges the positive and negative nature of each sampled data and encodes the results. While setting the time when the decoder 204 sends out a normal code as the measurement starting time, a counter 205 sets the number of waves of the beat signal to be zero and sets the state number of the code to be 1. A computing part 206 computes the displacement from the wave numbers and the state number of the code obtained from the counter 205.
Inventors:
Masayoshi Sugino
Yutaka Suzuki
Hisashi Kawai
Atsuko Yokoyama
Masahiro Sugimoto
Toyokazu Onishi
Yutaka Suzuki
Hisashi Kawai
Atsuko Yokoyama
Masahiro Sugimoto
Toyokazu Onishi
Application Number:
JP3227096A
Publication Date:
August 11, 2004
Filing Date:
February 20, 1996
Export Citation:
Assignee:
Japan Auto Parts Research Institute, Inc.
International Classes:
G01B11/00; G01B9/02; (IPC1-7): G01B9/02; G01B11/00
Domestic Patent References:
| JP835811A | ||||
| JP7201807A | ||||
| JP63126A | ||||
| JP5248817A | ||||
| JP2196906A |
Attorney, Agent or Firm:
Takashi Ishida
Shigeru Tsuchiya
Toshio Toda
Masaya Nishiyama
Shigeru Tsuchiya
Toshio Toda
Masaya Nishiyama