LB11-25-200 25.4 mm Dia. N-BK7 Double-Concave Lens; EFL=-200mm Uncoated

The LB11-25-200 is a high-quality double-concave lens offered by CeNing Optics, a renowned vendor in the optical industry. This lens, with a diameter of 25.4 mm, is designed for use in a variety of optical systems that require concave-concave geometry.

The lens's primary feature is its effective focal length (EFL) of -200mm, which is a measure of its optical power. A negative EFL indicates that this is a diverging lens, meaning it spreads out light rays that pass through it. This makes it suitable for applications where beam expansion is required.

The lens is made from N-BK7, a type of borosilicate glass known for its excellent optical properties. This material is chosen for its high transparency, low auto-fluorescence, and excellent homogeneity, making it an ideal choice for many optical applications.

The geometry of the lens includes a center thickness of 2 mm, and radii of curvature of -207.66 mm for the first surface and 207.66 mm for the second surface. These parameters are crucial in determining the lens's optical performance.

The lens is uncoated, meaning it does not have any additional layers applied to its surfaces to alter its optical properties. While this may result in a slightly lower transmission rate compared to coated lenses, it does offer the advantage of lower cost and simpler maintenance.

According to the vendor, this lens is currently in stock, ensuring quick delivery for those who need it. The product's webpage also provides additional information and specifications, making it a comprehensive resource for those considering this lens for their optical systems.