22-939 25mm Dia. N-SF6 Precision NIR Aspheric Lens; EFL=25mm; NA=0.5 Laser V-Coat 1550nm

This is the 22-939 model from Edmund Optics, a 25mm Dia. N-SF6 Precision NIR Aspheric Lens, specifically designed for use with a wavelength of 1550nm. The lens is made from N-SF6 Schott material, a high-refractive index glass that is often used in high-performance optical systems.

The lens features an effective focal length (EFL) of 25mm, providing a compact and efficient optical solution. The numerical aperture (NA) is 0.5, indicating a wide acceptance angle and high light-gathering capability. This makes the lens suitable for applications that require high light collection or transmission, such as imaging, beam shaping, or laser applications.

The lens has a circular base shape with a diameter of 25mm. The edge thickness is 4.25mm, and the center thickness is 8.5mm, providing structural rigidity and resistance to deformation. The lens also features an aspheric surface, which helps to reduce spherical aberration and improve optical performance. The aspheric surface is defined by a series of coefficients (k1, k2, etc.) and radii (r1, r2, etc.), which are used to calculate the precise surface shape.

The lens is coated with Edmund Optics' Laser V-Coat 1550, a broadband anti-reflection coating designed for use with 1550nm light. This coating reduces surface reflections, improving transmission and reducing unwanted back reflections. The coating is applied to both the front and back surfaces of the lens.