Broadband anti-reflection (BBAR) coatings are engineered to enhance transmission across a significantly wider wavelength range. They are frequently utilized with broad-spectrum light sources and lasers that produce multiple harmonics.
While BBAR coatings generally do not reach the extremely low reflectivity values of V-coats or Double-V coatings, their versatility in accommodating a broader transmission band makes them advantageous.
In addition to being applied to transmissive optical components such as lenses and windows, AR coatings are also employed on laser and nonlinear crystals to reduce reflections, as Fresnel reflections can occur at the interface between air and the crystal.
Additionally, BBAR coatings are durable and can withstand reasonably high levels of laser power fluence.
Broadband Anti-Reflection (BBAR) Coating Options
anti-reflection coating selection guide
MgF2: The simplest AR coating used is MgF2 centered at 550nm (with an index of refraction of 1.38 at 550nm). MgF2 coating is ideal for broadband use though it gives varied results depending upon the glass type involved.
VIS 0° and VIS 45°: VIS 0° (for 0° angle of incidence) and VIS 45° (for 45° angle of incidence) provide optimized transmission for 425 – 675nm, reducing average reflection to 0.4% and 0.75% respectively. VIS 0° AR coating is preferred over MgF2 for visible applications.
VIS-NIR: Our visible/near-infrared broadband anti-reflection coating is specially optimized to yield maximum transmission (>99%) in the near-infrared.
Telecom-NIR: Our telecom/near-infrared is a specialized broadband AR coating for popular telecommunications wavelengths from 1200 – 1600nm.
UV-AR and UV-VIS: Ultraviolet coatings are applied to our UV fused silica lenses and UV fused silica windows to increase their coating performance in the ultraviolet region.
NIR I and NIR II: Our near-infrared I and near-infrared II broadband AR coatings offer exceptional performance in near-infrared wavelengths of common fiber optics, laser diode modules, and LED lights.
SWIR: Shortwave infrared broadband AR coating for applications from 900 - 1700nm.
