Anomalous Performance of a Near-Infrared Beamsplitter
Abstract
This document describes an anomaly in the performance of a custom beamsplitter designed and fabricated by one of the major coatings vendors. Specifically, the beamsplitter exhibited a true absorption in the reflective portion of its wavelength range. The absorption was not detected initially by the vendor or the end user because only transmission acceptance tests were performed. This is not uncommon since transmission measurements are frequently easier to perform and because reflectance and transmittance are assumed to be related by the simple formula: reflectance = 1 - transmittance. This relation does not account for absorption, however, and the problem with this particular beamsplitter was not uncovered until it was installed into its host instrument. The lesson here is to acceptance check any beamsplitter over its full wavelength range in both reflection and transmission, testing it as it will be used.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 05, 2003
- Accession Number
- ADA417119
Entities
People
- J. D. Barrie
- R. J. Rudy
Organizations
- The Aerospace Corporation