Diffraction encoded position measuring apparatus

Patent · Tue Jan 01 00:00:00 EST 1991

OSTI ID:867996

Tansey, Richard J ^[1]

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1. Thousand Oaks, CA

When a lightwave passes through a transmission grating, diffracted beams appear at the output or opposite side of the grating that are effectively Doppler shifted in frequency (phase) whereby a detector system can compare the phase of the zero order and higher order beams to obtain an indication of position. Multiple passes through the grating increase resolution for a given wavelength of a laser signal. The resolution can be improved further by using a smaller wavelength laser to generate the grating itself. Since the grating must only have a pitch sufficient to produce diffracted orders, inexpensive, ultraviolet wavelength lasers can be utilized and still obtain high resolution detection.

• Research Organization: Rockwell International Corp., Canoga Park, CA (United States)
• DOE Contract Number: AC03-86SF16499
• Assignee: Rockwell International Corporation (El Segundo, CA)
• Patent Number(s): US 5050993
• OSTI ID: 867996
• Country of Publication: United States
• Language: English

Related Subjects

diffraction
encoded
position
measuring
apparatus
lightwave
passes
transmission
grating
diffracted
beams
appear
output
opposite
effectively
doppler
shifted
frequency
phase
whereby
detector
compare
zero
obtain
indication
multiple
increase
resolution
wavelength
laser
signal
improved
generate
pitch
sufficient
produce
inexpensive
ultraviolet
lasers
utilized
detection
wavelength laser
multiple passes
ultraviolet wavelength
multiple pass
measuring apparatus
doppler shift
diffracted beam
transmission grating
wavelength lasers
diffracted beams
laser signal
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