Coherent Optical Mapping Techniques.
Abstract
Coherent optical data processing techniques were investigated for automatic matching and parallax measurement. The study included image plane correlators with amplitude spatial filters and frequency plane correlators with complex spatial filters, i.e., Fourier transform holograms. Classical interferometry was also investigated for application to contouring. The various optical systems were arranged to study 'point' image measurements as well as multichannel parallel measurements for a multiplicity of image points. An image plane optical correlator with amplitude spatial filters has been automated to provide on-line servo control of photo carriages and detection of perspective image distortion. Experimental results are presented. The use of prismatic anamorphs to obtain continuously variable anamorphic magnification in coherent optical correlators for slope correction is discussed. Matched-filter (Fourier transform hologram) correlators for image parallax measurement and reseau detection are described with experimental results. Perspective contours in photocoordinates were obtained using a modified Mach-Zehnder interferometer. Power spectra of planimetric features are presented. The photogrammetric application of multichannel parallel processors for profiling and contouring is restricted to rectified or normal coplanar photography. The use of optical matched-filter correlators for reseau detection is considered practical, and such frequency plane correlators for image parallax measurement show great potential for increasing speed of measurement. Continued study is recommended.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1970
- Accession Number
- AD0870942
Entities
People
- Dan C. Kowalski
- Juan C. Dawson
- Stanley J. Krulikoski