COLLIMATED LIGHT SOURCE STUDY.
Abstract
Techniques to enhance the viewing of aerial reconnaissance film by modification of the illumination section of existing microscopes were theoretically and experimentally investigated. Theoretically, a technique was described for predicting the transfer function of an optical system as a function of illumination. It was shown that the spatial frequency content of the imagery being viewed, as well as the human eye response, play a role in determining the optimum transfer function. Two stereo microscopes commonly used for photointerpretation, a Bausch and Lomb Zoom 70 and a Wild-5, were used in the study. The course of action chosen to investigate the problem was to measure the square wave response (SWR) of the microscopes using several types of illumination. Curves of output modulation (contrast) versus spatial frequency in the object plane were constructed for each particular configuration and compared with each other. The types of illumination tested included diffuse white light, coherent laser illumination, oblique illumination, collimated white light, diverging white light and illumination through a honeycomb element. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1968
- Accession Number
- AD0837609
Entities
People
- C. M. Cykowski
- D. A. Ansley