title: Precision passive range measurement.
abstract: Image feature analysis to determine object distance can provide precision performance if the optical point-spread function is highly sensitive to range. In the method presented here, a specially designed mask imparts a quarter-wave phase shift over part of the input aperture, thereby inducing an interference effect with maximum sensitivity. The resultant image can be compared with a conventional image through deconvolution and least-squares fitting in order to extract a precise range estimate. This method is quantitatively examined through computer modeling and laboratory testing and is broadly applicable to a wide range of optical wave bands.
authors.affiliation: LightLine Technologies Inc., Needham, Massachusetts 02492, USA. Stevenlis@comcast.net
authors.forename: Steven A
authors.initials: SA
authors.lastname: Lis
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation* / Q000379:methods*; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity