37-424 20mm Dia. N-SF6 Precision Aspheric Lens; EFL=15mm; NA=0.67 Uncoated

The 37-424 is a high-precision aspheric lens offered by Edmund Optics. This lens, with a catalog number 37-424, is made from N-SF6 Schott, a high-quality optical glass known for its excellent transmittance and homogeneity. The lens is uncoated, which means it does not have any additional layers to enhance its optical properties.

The lens has a base shape of a circle and a diameter of 20mm. It has an effective focal length (EFL) of 15mm, which is the distance from the lens's principal point to the focal point when the lens is focused at infinity. The lens's numerical aperture (NA) is 0.67, indicating its ability to gather and focus light.

The lens's geometry is defined by several parameters. The inner radius is 0, and the outer radius is also 0, indicating a symmetrical lens. The thickness at the edge is 7.97mm, and the thickness at the center is 12.42mm. The back focal length (BFL) is 8.12mm.

The lens's shape is aspheric, meaning it is not a simple sphere or cylinder. The aspheric shape helps to correct spherical aberration, a common optical problem where light rays do not focus at the same point. The lens's aspheric profile is defined by several coefficients, including k1, k2, and others, which control the curvature of the lens.

The lens is designed for use at a wavelength of 587.6nm, which is in the yellow-green part of the visible spectrum. It is suitable for use in various applications, including imaging, illumination, and beam shaping.