Thorlabs LA1304-B Plano-Convex Lens

Key Specifications

• Type: Plano-convex spherical lens

• Material: N-BK7 glass

• Diameter: 12.7 mm (½″)

• Focal Length (EFL): ~40.0 mm (nominal 39.9 mm)

• Back Focal Length (BFL): ~38.0 mm

• Center Thickness: ~2.8 mm

• Edge Thickness: ~1.8 mm

• Clear Aperture: > 90%

• Coating: Broadband AR (“-B” coating) for 650–1050 nm

• Design Wavelength: 587.6 nm

• Abbe Number: ~64.17

Applications / Use Cases

• Good for focusing or collimating light in the 650–1050 nm wavelength range.

• Commonly used in optical setups, lab experiments, imaging systems, or any system where a small, well-corrected singlet lens is needed.

• Because it’s plano-convex, it’s especially suitable for minimizing spherical aberration when used properly (e.g., putting a collimated beam onto the curved surface).