Antireflective Coatings

Andover produces a non-radioactive dielectric multilayer coating designed to reduce the reflection of Germanium substrates in the infrared. Reflection is reduced from 36% per surface to less than 1% per surface. Constructed of hard, durable first-surface dielectric coatings on optical-quality germanium substrates, these filters will withstand cleaning and handling associated with any high-quality optical component. For your convenience and economy, we offer the filters in two standard sizes: 25 mm and 50 mm dia. However, we can produce custom sizes and shapes, as well as custom optical characteristics. Contact our technical sales department for a quotation.

General Specifications
Thickness:	1.0 ±.2mm
Diameter Tolerance:	+0/-.1mm
Min. Clear Aperture:	90% of outside dimension
Substrate Material:	Germanium (other substrates available)
Flatness:	2 waves at 632.8nm
Parallelism:	<10 arc minutes
Surface Quality:	80/50 per MIL-C-48497A
Coating Quality:	80/50 per MIL-C-48497A
24-hour humidity:	per MIL-C-48497A
Moderate Abrasion:	per MIL-C-48497A
Adhesion:	per MIL-C-48497A
Operating Temperature:	-62°C to +71°C
Mechanical:	Unmounted