LB1761 N-BK7 Bi-Convex Lens; Dia:1 in; f=25.4 mm Uncoated

The LB1761 N-BK7 Bi-Convex Lens is a high-quality optical component sourced from Thorlabs, a leading vendor in the field of optical equipment. This lens, with a diameter of 1 inch and a focal length of 25.4 mm, is designed for use in a wide range of optical systems, making it a versatile choice for various applications.

The lens is made of N-BK7, a type of borosilicate glass known for its excellent optical properties. This material is characterized by a low coefficient of thermal expansion, making it resistant to thermal shock and suitable for use in environments with varying temperatures. The N-BK7 material also offers high homogeneity and excellent transmission in the visible and near-infrared regions of the spectrum.

The LB1761 lens features a bi-convex geometry, meaning it has two spherical surfaces that are both convex, or outwardly curved. This shape is designed to focus light to a single point, making it ideal for use in imaging systems, beam shaping, and other applications where light focusing is required. The lens has an effective focal length (EFL) of 25.4 mm, which is the distance from the lens to the point where it focuses light.

The lens has a diameter of 25.4 mm, and its edge thickness is 1.9 mm, while its center thickness is 9 mm. These dimensions are crucial for determining how the lens will fit into an optical system and how it will interact with other components. The lens also has a back focal length (BFL) of 22.2 mm, which is the distance from the rear surface of the lens to the point where it focuses light.

Notably, this lens is uncoated. While coatings can be applied to lenses to reduce reflection, increase transmission, or protect the lens surface, an uncoated lens can be a cost-effective choice for applications where these features are not critical.