Our partner Andover Corp.

Broadband AR coating on germanium

from Andover

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 expert on the right for a quotation.

  • Reduces reflection from 36% to 1% per surface
  • Constructed of hard, durable and non-radioactive materials
  • Meets MIL-C-48497


General Specifications
Thickness 1.0±0.2 mm
Diameter Tolerance +0/-0.1 mm
Min. Clear Aperture 90% of outside dimension
Substrate Material Germanium (other substrates available
Flatness 2 waves at 632.8 nm
Parallelism < 10 arc minutes
Sufrace Quality 60/40 per MIL-C-48497A
Coating Quality 60/40 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
Optional Mounted in threaded ring
AR Coating 25 mm Ø 50 mm Ø
3-5 µm coated Germanium Window GEBBAR-3-5-25 GEBBAR-3-5-50
8-12 µm coated Germanium Window GEBBAR-8-12-25 GEBBAR-8-12-50
8-14 µm coated Germanium Window GEBBAR-8-14-25 GEBBAR-8-14-50
2-14 µm coated Germanium Window GEBBAR-2-14-25 GEBBAR-2-14-50


Thermal Imaging
Detector Windows
Dewar Windows


Quantum Design

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199 00 Praha 9
Czech Republic

Phone:+420 607 014 278