LB1901 N-BK7 Bi-Convex Lens; Dia:1 in; f=75.0 mm Uncoated

The LB1901 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 75.0 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 LB1901 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 a clear aperture of 1 inch, providing a wide field of view and allowing for high light-gathering capabilities. The edge thickness of the lens is 2 mm, while the center thickness is 4.1 mm, providing robustness and stability. The effective focal length (EFL) of the lens is 75 mm, which, combined with its diameter, gives it a high f-number (f/75), indicating a narrow aperture and a greater depth of field.

Notably, this lens is uncoated. While coatings can be applied to enhance the lens's performance, such as by reducing reflections or increasing transmission, this lens is designed to operate effectively without them. This makes it a cost-effective choice for many applications.