• Diameter: Ø50.8 mm
• Wavelength Range: 185 nm - 2.1 µm (uncoated)
• Focal Length: 1000 mm
• Fabricated from UV Grade Fused Silica
• Spherical Surface Power: 3 Fringes
• Spherical Surface Irregularity: ?/4

Thorlabs' UV Grade Fused Silica Positive Meniscus Lens is uncoated. Compared to N-BK7, UV-grade fused silica offers high transmission deeper into the UV (down to 185 nm), better homogeneity, and a lower coefficient of thermal expansion. In addition, UV fused silica exhibits virtually no laser-induced fluorescence (as measured at 193 nm), making it an ideal choice for applications from the UV to the near IR.

A positive meniscus (convex-concave) lens, which is thicker in the middle than at the edges and cause light rays to converge, is designed to minimize third-order spherical aberration. It is often used in conjunction with other lenses to decrease the focal length, and therefore increase the numerical aperture (NA), of an optical assembly. When used to focus a collimated beam, as shown in the diagram above, the convex side of the lens should face the source to minimize spherical aberration. Since a positive meniscus lens has a greater radius of curvature on the concave side of the lens than on the convex side, real images can be formed.

• Lens Shape: Positive Meniscus
• Diameter: Ø50.8 mm
• Diameter Tolerance: +0.00 mm / -0.10 mm
• Substrate Material: UV Grade Fused Silica
• Wavelength Range: 185 nm - 2.1 µm
• Transmission Internal: = 88%/cm @ 185 nm
• Focal Length Tolerance: ±1%
• Surface Quality: 40-20 Scratch-Dig
• Clear Aperture: >90% of Diameter
• Design Wavelength: 588 nm (n=1.460)
• Index of Refraction: (@ Design ?) 1.460
• Centration: =3 arcmin
• f: 1000 mm
• R₁: 356.7 mm
• R₂: 1580.2 mm
• t_c: 5 mm
• t_e: 4.3 mm
• f_b: 995.6 mm
• Suggested Mount: LMR2