89-611 25mm Dia. Germanium Infrared Aspheric Lens; EFL=30mm; NA=0.42 BBAR 3-12µm

The 89-611 is a high-quality aspheric lens, designed for infrared applications, available from Edmund Optics. This lens boasts a 25mm diameter and a focal length of 30mm, making it suitable for a wide range of optical systems. The lens is constructed from germanium, a material known for its excellent transmission properties in the infrared spectrum.

The aspheric design of this lens is a significant advantage, as it helps to reduce spherical aberration, a common issue in optical systems. This is achieved through the precise shaping of the lens, which deviates from the standard spherical shape. The result is a lens that provides superior image quality, with less distortion and greater clarity.

The lens features a broadband anti-reflection coating, designed to operate between 3µm and 12µm. This coating helps to minimize surface reflections, improving the overall efficiency of the lens and reducing the likelihood of unwanted glare or ghosting.

The lens has a numerical aperture (NA) of 0.42, which is a measure of the lens' light-gathering ability. A higher NA allows for a wider field of view and greater resolution, making this lens ideal for applications that require high-precision imaging.

The lens is 2.29mm thick at the edge and 3.25mm thick at the center. The front and back surfaces of the lens are coated with Edmund Optics' ARC EDGermanium31 coating, providing excellent protection and performance.