Micro Achromatic Doublet Lens (Endoscope Grade) — Ø2 mm, N-BK7 / N-SF6 / N-PSK53A
Specifications
Lens Type: Achromatic Doublet (Cemented), Positive or Negative
Outer Diameter: 2.00 mm (+0.000 / –0.025 mm)
Effective Focal Length (EFL): 4.0 mm / 6.0 mm / 8.0 mm / 12.0 mm standard (custom EFL available)
Back Focal Length (BFL): Typically 2.5–10.0 mm (depends on EFL configuration)
Center Thickness (Total): 1.00 – 2.00 mm (varies by design)
Clear Aperture: > 1.6 mm (> 80% of OD)
Surface Quality: 20-10 or 40-20 Scratch-Dig (per MIL-PRF-13830B)
Surface Flatness / Irregularity: λ/4 @ 546.1 nm; λ/8–λ/10 irregularity optional
Centration Error: ≤ 3 arcmin (≤ 1 arcmin on request)
Glass Combination Examples: N-BK7 / N-SF6 (standard achromat); N-PSK53A / N-SF57 (apochromat-like correction); UVFS / CaF₂ (UV-VIS)
Adhesive: UV-curing optical epoxy (low shrinkage, high transmission 350–2000 nm)
Coating Options: Uncoated / MgF₂ single-layer / BBAR (400–700 nm, Ravg < 0.5%) / BBAR (650–1050 nm) on both air-glass surfaces
Wavelength Range: 420–680 nm (VIS); 340–900 nm (extended VIS-NIR on UVFS combos)
Operating Temperature: –20°C to +80°C (standard epoxy)
Bevel / Chamfer: Protective bevel 0.03–0.08 mm × 45°
