Backscatter Haze Device for Measurement of Haze in Aircraft Transparencies
Abstract
The method currently used throughout the aircraft transparency industry to measure haze is ASTM Test Method D1003. This procedure was originally developed for applications involving small, thin, and flat transparent parts. Major limitations of Test Method D1003 include its restriction to small, flat samples and its requirement for having the source and detector on opposite sides of the sample under test. In order to facilitate field testing of installed aircraft windscreens, a test method was developed which overcomes the limitations of Test Method D1003. The new method determines haze values by measuring the amount of light backscattered off the surface of the transparency under test. A prototype instrument was developed and tested against D1003. The results of those tests are presented. The new instrument consists of an integrating sphere, a mechanically chopped incandescent light source, a silicon detector, and supporting electronics. This report describes the device, which is based on US Patent Number 4,687,338, in detail. Use of this type of device in the field could provide quantitative data for determining when an installed aircraft windscreen should be replaced or refinished in place. Aircraft transparencies, Haze ASTM Test Method D1003, Surface topography, Scattering, Diffraction, Integrating sphere, Silicon detector, Chopped light source, Signal processing, Field evaluations.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1993
- Accession Number
- ADA275127
Entities
People
- H. L. Task
- Richard J. Bartell
- Sheldon E. Unger