LB1889-C N-BK7 Bi-Convex Lens; Dia:2 in; f=250.0 mm ARC 1050-1700nm
- Type
- Lens
- Subtype
- Spherical Lens (Convex-Convex)
- Brand
- Thorlabs
Properties
- Shape
- Circular
- Diameter
- 50.8 mm
- EFL
- 125 mm
- BFL
- 248.2 mm
- R1
- 256.6 mm
- R2
- -256.6 mm
Material
- Name
- N-BK7
- Dispersion Equation
- Sellmeier
- n (λ)
- 1.5150823520020043
- λ
- 633 nm
- B1
- 1.03961212
- C1
- 0.00600069867 μm2
- B2
- 0.231792344
- C2
- 0.0200179144 μm2
- B3
- 1.01046945
- C3
- 103.560653 μm2
LB1889-C N-BK7 Bi-Convex Lens; Dia:2 in; f=250.0 mm ARC 1050-1700nm
The LB1889-C is a high-quality bi-convex lens from Thorlabs, designed for use in a wide range of optical applications. This lens is fabricated from N-BK7 Schott glass, a popular material known for its excellent optical properties and versatility.
The lens features a diameter of 2 inches (50.8 mm) and a focal length of 250.0 mm, providing a beam divergence that is suitable for many applications. The lens has a double-convex shape, with radii of curvature of 256.6 mm for the first surface and -256.6 mm for the second surface. This shape allows for efficient light collection and focusing.
The LB1889-C is coated with Thorlabs' Broadband Anti-Reflection Coating (BBAR), which is designed to reduce surface reflections and increase transmission across the 1050-1700nm wavelength range. This coating ensures optimal performance in near-infrared applications.
The lens has a central thickness of 9.5 mm and an edge thickness of 3 mm, providing robustness and durability. The lens is also available with custom AR coatings upon request, allowing for tailored performance in specific applications.