E-45-221 25mm Dia x -50mm FL Negative Doublet Lens MgF2 Coated
E-45-221 25mm Dia x -50mm FL Negative Doublet Lens MgF2 Coated
Diameter (mm): 25.00 +0.0/-0.025
Effective Focal Length EFL (mm): -50.00
Focal Length Tolerance (%): ±1
Back Focal Length BFL (mm): -53.33
Focal Length Specification Wavelength (nm): 587.6
Clear Aperture CA (mm): 24.00
Centering (arcmin): <1
Center Thickness CT 1 (mm): 2.50
Center Thickness CT 2 (mm): 4.06
Center Thickness Tolerance (mm): ±0.2
Radius R1 (mm): -35.51
Radius R2 (mm): 24.58
Radius R3 (mm): 217.99
Edge Thickness ET (mm): 9.06
f/#: 2.00
Numerical Aperture NA: 0.25
Coating: MgF2 (400-700nm)
Coating Specification: Ravg ≤1.75% @ 400 - 700nm
Power (P-V) @ 632.8nm: 1.5λ
Irregularity (P-V) @ 632.8nm: λ/4
Bevel: Protective bevel as needed
Type: Negative Achromatic Lens
Wavelength Range (nm): 400 - 700
Product Family Description
- Magnesium Fluoride (MgF2) Coating
- Used to Extend Focal Length
TECHSPEC® MgF2 Coated Negative Achromatic Lenses consist of two optical elements cemented together. Negative doublet lenses are corrected for color and on-axis aberrations. TECHSPEC MgF2 Coated Negative Achromatic Lenses are used predominantly as Barlow lenses to extend focal lengths. These lenses are often combined with positive achromatic mirror systems and imaging lenses.