• Ø50.8 mm Bi-Convex Lens
• Material: N-BK7 (Abbe Number: 64.17)
• Wavelength Range: 350 nm – 2 µm
• Focal Length: 750 mm
• Surface Quality: 40-20 Scratch-Dig

The LB1247 uncoated N-BK7 Bi-Convex lens is popular for many finite imaging applications. This lens is best suited for use in situations where the object and image are on opposite sides of the lens and the ratio of the image and object distances (conjugate ratio) is between 0.2 and 5.0.

N-BK7 is probably the most common optical glass used for high-quality optical components. It is typically chosen whenever the additional benefits of UV fused silica (i.e., good transmission further into the UV and a lower coefficient of thermal expansion) are not necessary.

• Lens Shape: Convex / Convex
• Material: N-BK7 (Grade A)
• Wavelength Range: 350 nm – 2 µm
• Design Wavelength: 587.6 nm
• Index of Refraction at 633 nm: 1.515
• Surface Quality: 40-20 Scratch-Dig
• Spherical Surface Power: 3 fringes
• Surface Irregularity: λ/4
• Abbe Number: v_d=64.17
• Centration: ≤3 arcmin
• Clear Aperture: > 90% of Diameter
• Diameter Tolerance: +0.00 mm / -0.10 mm
• Focal Length Tolerance: ±1%
• Diameter: 50.8 mm
• f: 750 mm
• R: 772 mm
• t_c: 3.8 mm
• t_e: 3 mm
• f_b: 748.7 mm
• Suggested Fixed Lens Mount: LMR2