The Heat of the Night and the Dust of the Battlefield

doi:10.1117/3.349896.ch0

Book: Materials for Infrared Windows and Domes: Properties and Performance

Author(s): Daniel C. Harris

Published: 1999

https://doi.org/10.1117/3.349896.ch0

Author Affiliations +

Abstract

All objects above absolute zero temperature emit infrared radiation. This radiation can be used to measure the temperature of an object in a laboratory or factory, or can be used to observe military targets on a battlefield. âHeat-seekingâ missiles use infrared radiation from the hot exhaust of a target aircraft to guide themselves to their prey. The nose of the infrared-guided missile in Fig. 0.1 is a hemispheric, infrared-transparent dome made of magnesium fluoride. The ceramic dome protects a delicate, hermetically sealed infrared seeker from the harsh environment of high speed missile flight. The dome must withstand rapid aerothermal heating when the missile is launched and must resist long term erosion from raindrops and dust encountered during captive carry of the missile beneath the wing of an aircraft. This book discusses optical, mechanical and thermal properties of infrared window and dome materials. It describes fabrication techniques and coatings required to enhance optical transmission and mechanical durability and to reject undesired radiation. We will emphasize the few rugged materials meant for external use in demanding environments, but will also mention important materials that can only be used in benign situations.