69-863 12.5 mm Dia. L-BAL35 Precision Aspheric Lens; EFL=12.5mm; NA=0.5 BBAR 600-1050nm

The 69-863 is a high-precision aspheric lens offered by Edmund Optics, featuring a 12.5 mm effective focal length (EFL) and a numerical aperture (NA) of 0.5. This lens is made from L-BAL35, a material manufactured by Ohara, and is specifically designed for use in the near-infrared (NIR) region of the spectrum, with a central wavelength of 587.6 nm.

The lens boasts a diameter of 12.5 mm and a thickness at the edge of 2.11 mm. The front and back surfaces of the lens are coated with BBAR (Broadband Anti-Reflection) coatings, which are optimized for the 600-1050 nm range, reducing surface reflections and improving transmission.

The lens's aspheric design allows for superior optical performance compared to traditional spherical lenses, minimizing spherical aberration and distortion. The geometry of the lens includes an inner radius of 0 mm, an outer radius of 0 mm, a thickness at the center of 5 mm, and a back focal length (BFL) of 9.35 mm.

The lens's shape is defined by its aspheric profile, with a conic constant of -1.058074 and higher-order aspheric terms. The front surface of the lens has an e-flate of 0.000157393, a flattening factor that contributes to the lens's excellent optical performance.