This is a double-concave lens, type Spherical Lens (Concave-Concave), offered by Standa. The lens has a base shape of Circular and is sourced from the vendor's Double Concave Lenses category. The lens is uncoated, offering a clean, unaltered optical path.
The lens has a diameter of 12.7 mm and a thickness at the edge of 2 mm. The center thickness is 1.7 mm. The effective focal length (EFL) is 125 mm. The first radius of curvature (R1) is -129.9646638 mm, and the second radius of curvature (R2) is 129.9646638 mm. The lens does not have an inner or outer radius.
The lens is made of n-bk7 schott material, a popular choice for its high refractive index and low dispersion. The lens is designed to operate at a wavelength of 546 nm.
Please note that the lens is a Spherical type, which means it has a spherical surface. This type of lens is commonly used in optical systems where a gradual curvature is required.
For more information, including availability and pricing, please refer to the vendor's website at http://www.standaphotonics.com/lenses/double-concave-lenses.php.