During service, Infrared Search and Track (IRST) domes develop pits and surface damage due to exposure to adverse environments such as sandstorms, rain, and fog. This damage accumulates over time eventually reducing the average transmission to below acceptable limits.
New domes are expensive since they are produced from single-crystal germanium with very sophisticated inner and outer surface coatings. Hence, a process is needed that is capable of restoring the damaged domes to a state or condition that meet all the imaging and environmental requirements of the original dome.
To address that issue, Surmet Corporation (Burlington, MA, USA) has been awarded a Small Business Innovation Research (SBIR) award from the US Navy to demonstrate the feasibility of a process to refurbish IRST domes that deteriorate in service.
Surmet will use its experience in applying IR transparent coatings and precision optical fabrication technologies to develop the technique to bring the damaged and worn-out domes back to the optical performance specifications of an original dome.
The process will involve removing the damaged surface layer and replacing it by a strongly adherent, durable and coating layer that is IR transparent. After machining, an anti-reflection (DAR) coating will be applied to provide abrasion resistance while enhancing IR transmission.
In addition to yielding a compliant dome, the company says that the refurbishment process may also improve the dome's durability.
Recent articles on infra-red imaging from Vision Systems Design.
1. Infrared imaging sensors to spot asteroid threats
The non-profit B612 Foundation has signed a contract with Ball Aerospace and Technologies (Broomfield, CO, USA) that will see engineers at Ball create prototype infrared imaging sensors for use on B612's Sentinel spacecraft which aims is to detect asteroids that might pose a threat to the Earth.
2. Near infrared spectroscopy determines the hardness of corn grains
A near infrared (NIR) spectroscopy imaging technique can determine the hardness of corn grains without destroying them. The new technique could offer food processors savings in time and money compared to other methods for determining grain hardness.
3. Scientists create faster, more sensitive infrared photodetector
Researchers at the Center for Nanophysics and Advanced Materials of the University of Maryland (UMD; College Park, MD, USA) have developed a new type of infrared detector that could potentially be used in airport body scanners.
-- Dave Wilson, Senior Editor, Vision Systems Design