This is a Plano-Concave Lens from Standa, a renowned vendor in the optical industry. The lens, which has a base shape of a circle, is designed with a diameter of 12.7 mm and a thickness that varies from 3.3 mm at the center to 3.5 mm at the edge. The lens's effective focal length (EFL) is -200 mm, indicating that it is a diverging lens.
The lens's geometry is defined by its inner and outer radii, which are both 0 in this case. The radius of curvature (R1) is -103.74 mm. This negative value indicates that the first surface of the lens is concave.
The lens is made of n-BK7 Schott, a popular optical glass known for its excellent optical properties. The lens is uncoated, which means it does not have any additional layers to enhance its optical performance or protect it from environmental factors.
This lens is designed to work with a wavelength of 546 nm. It is important to note that the performance of the lens can vary depending on the wavelength of the light it is used with.