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Title: Optical pattern recognition architecture implementing the mean-square error correlation algorithm

Abstract

An optical architecture implementing the mean-square error correlation algorithm, MSE=.SIGMA.[I-R].sup.2 for discriminating the presence of a reference image R in an input image scene I by computing the mean-square-error between a time-varying reference image signal s.sub.1 (t) and a time-varying input image signal s.sub.2 (t) includes a laser diode light source which is temporally modulated by a double-sideband suppressed-carrier source modulation signal I.sub.1 (t) having the form I.sub.1 (t)=A.sub.1 [1+.sqroot.2m.sub.1 s.sub.1 (t)cos (2.pi.f.sub.o t)] and the modulated light output from the laser diode source is diffracted by an acousto-optic deflector. The resultant intensity of the +1 diffracted order from the acousto-optic device is given by: I.sub.2 (t)=A.sub.2 [+2m.sub.2.sup.2 s.sub.2.sup.2 (t)-2.sqroot.2m.sub.2 (t) cos (2.pi.f.sub.o t] The time integration of the two signals I.sub.1 (t) and I.sub.2 (t) on the CCD deflector plane produces the result R(.tau.) of the mean-square error having the form: R(.tau.)=A.sub.1 A.sub.2 {[T]+[2m.sub.2.sup.2.multidot..intg.s.sub.2.sup.2 (t-.tau.)dt]-[2m.sub.1 m.sub.2 cos (2.tau.f.sub.o .tau.).multidot..intg.s.sub.1 (t)s.sub.2 (t-.tau.)dt]} where: s.sub.1 (t) is the signal input to the diode modulation source: s.sub.2 (t) is the signal input to the AOD modulation source; A.sub.1 is the light intensity; A.sub.2 is the diffraction efficiency; m.sub.1 and m.sub.2 are constants that determine the signal-to-bias ratio; f.sub.o is the frequency offsetmore » between the oscillator at f.sub.c and the modulation at f.sub.c +f.sub.o ; and a.sub.o and a.sub.1 are constant chosen to bias the diode source and the acousto-optic deflector into their respective linear operating regions so that the diode source exhibits a linear intensity characteristic and the AOD exhibits a linear amplitude characteristic.

Inventors:
 [1]
  1. Albuquerque, NM
Issue Date:
Research Org.:
AT&T
OSTI Identifier:
868040
Patent Number(s):
5060282
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
G - PHYSICS G06 - COMPUTING G06E - OPTICAL COMPUTING DEVICES
DOE Contract Number:  
AC04-76DP00789
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
optical; pattern; recognition; architecture; implementing; mean-square; error; correlation; algorithm; sigma; i-r; discriminating; presence; reference; image; input; scene; computing; mean-square-error; time-varying; signal; laser; diode; light; source; temporally; modulated; double-sideband; suppressed-carrier; modulation; form; sqroot; 2m; cos; output; diffracted; acousto-optic; deflector; resultant; intensity; device; -2; time; integration; signals; ccd; plane; produces; result; tau; multidot; intg; t-; dt; aod; diffraction; efficiency; constants; determine; signal-to-bias; ratio; frequency; offset; oscillator; constant; chosen; bias; respective; linear; operating; regions; exhibits; characteristic; amplitude; reference image; signal input; modulation signal; image signal; pattern recognition; light source; laser diode; light intensity; light output; mean-square error; modulated light; time integration; optic device; linear intensity; diffraction efficiency; error correlation; frequency offset; optical pattern; amplitude characteristic; architecture implementing; correlation algorithm; /382/359/

Citation Formats

Molley, Perry A. Optical pattern recognition architecture implementing the mean-square error correlation algorithm. United States: N. p., 1991. Web.
Molley, Perry A. Optical pattern recognition architecture implementing the mean-square error correlation algorithm. United States.
Molley, Perry A. Tue . "Optical pattern recognition architecture implementing the mean-square error correlation algorithm". United States. https://www.osti.gov/servlets/purl/868040.
@article{osti_868040,
title = {Optical pattern recognition architecture implementing the mean-square error correlation algorithm},
author = {Molley, Perry A},
abstractNote = {An optical architecture implementing the mean-square error correlation algorithm, MSE=.SIGMA.[I-R].sup.2 for discriminating the presence of a reference image R in an input image scene I by computing the mean-square-error between a time-varying reference image signal s.sub.1 (t) and a time-varying input image signal s.sub.2 (t) includes a laser diode light source which is temporally modulated by a double-sideband suppressed-carrier source modulation signal I.sub.1 (t) having the form I.sub.1 (t)=A.sub.1 [1+.sqroot.2m.sub.1 s.sub.1 (t)cos (2.pi.f.sub.o t)] and the modulated light output from the laser diode source is diffracted by an acousto-optic deflector. The resultant intensity of the +1 diffracted order from the acousto-optic device is given by: I.sub.2 (t)=A.sub.2 [+2m.sub.2.sup.2 s.sub.2.sup.2 (t)-2.sqroot.2m.sub.2 (t) cos (2.pi.f.sub.o t] The time integration of the two signals I.sub.1 (t) and I.sub.2 (t) on the CCD deflector plane produces the result R(.tau.) of the mean-square error having the form: R(.tau.)=A.sub.1 A.sub.2 {[T]+[2m.sub.2.sup.2.multidot..intg.s.sub.2.sup.2 (t-.tau.)dt]-[2m.sub.1 m.sub.2 cos (2.tau.f.sub.o .tau.).multidot..intg.s.sub.1 (t)s.sub.2 (t-.tau.)dt]} where: s.sub.1 (t) is the signal input to the diode modulation source: s.sub.2 (t) is the signal input to the AOD modulation source; A.sub.1 is the light intensity; A.sub.2 is the diffraction efficiency; m.sub.1 and m.sub.2 are constants that determine the signal-to-bias ratio; f.sub.o is the frequency offset between the oscillator at f.sub.c and the modulation at f.sub.c +f.sub.o ; and a.sub.o and a.sub.1 are constant chosen to bias the diode source and the acousto-optic deflector into their respective linear operating regions so that the diode source exhibits a linear intensity characteristic and the AOD exhibits a linear amplitude characteristic.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1991},
month = {Tue Jan 01 00:00:00 EST 1991}
}