SLB-20B-20P 20.0 mm Dia. x 21.2 mm FL; Double-Convex Lens Uncoated

The SLB-20B-20P is a high-quality double-convex lens offered by OptoSigma, a leading vendor in the optical industry. This lens, with a base shape of a circle, is designed for use in a wide range of optical applications.

The lens has a diameter of 20.0 mm and a center thickness of 7.1 mm, ensuring a robust and durable construction. The edge thickness is 2.0 mm, providing additional strength and resistance to wear and tear. The effective focal length (EFL) of this lens is 21.2 mm, making it suitable for applications requiring a longer focal length.

The SLB-20B-20P is made from n-BK7 Schott, a popular optical glass due to its excellent optical properties and high Abbe number. This material ensures high transmittance and low dispersion, making it ideal for various applications, including imaging, beam shaping, and laser systems.

The lens's surface radii are 20.76 mm for the first surface and -20.76 mm for the second surface, indicating a strongly converging lens. The back focal length (BFL) is 18.8 mm, which is the distance from the rear surface of the lens to the image plane when the lens is focused at infinity.

This lens is uncoated, which means it does not have any anti-reflective coatings. While this may result in higher reflective losses, it also means the lens is less susceptible to damage from environmental factors, making it a practical choice for certain applications.