The 21-925 is a high-performance aspheric lens, designed and manufactured by Edmund Optics. This lens is characterized by its 25mm diameter and a numerical aperture (NA) of 0.15, making it suitable for a wide range of applications within the UV-VIS spectrum, specifically between 250-700nm.
The lens is constructed from HPFS7980 Corning, a high-quality fused silica material known for its excellent transmission properties and durability. The aspheric design of the lens helps to minimize spherical aberration, enhancing the overall image quality and resolution.
The geometry of the lens includes an inner radius of 0mm, an outer radius of 0mm, a thickness at the edge of 3.78mm, and an effective focal length (EFL) of 75mm. The lens's front surface has a radius of curvature (R1) of 35.707004mm, while the back surface (R2) is flat. The back focal length (BFL) is 70.9mm, and the thickness at the center is 6mm.
The lens comes with standard UV-VIS coatings on both the front and back surfaces, according to Edmund Optics' standard curve. This coating enhances the lens's transmission properties and protects it from environmental damage.