This is the HO-BVL25-02B 25mm Dia. N-BK7 Double-Concave Lens, a high-quality optical component sourced from Holmarc Opto-Mechatronics. The lens is a Spherical Lens of the Sub Type Spherical Lens (Concave-Concave), featuring a Base Shape of Circular.
The lens has a diameter of 25mm and a center thickness of 2.5mm. The Effective Focal Length (EFL) is -50mm, indicating that it is a double-concave lens. The first radius of curvature (R1) is -53.085436, and the second radius of curvature (R2) is 53.085436. The Inner Radius and Outer Radius are both 0, suggesting a symmetrical design.
The lens is made of N-BK7 Schott, a popular optical glass known for its excellent optical properties. It is designed to operate at a wavelength of 587.6nm. The lens features a BBAR (Broadband Anti-Reflection) coating on both the front and back surfaces, which enhances its transmission capabilities in the 400-700nm range.
This lens is currently in stock and available for purchase through the Holmarc Opto-Mechatronics website. For more information, please refer to the provided weblink.