68-250 25mm Dia. Germanium Infrared Aspheric Lens; EFL=75mm; NA=0.17 BBAR 3-5µm
- Type
- Lens
- Subtype
- Aspheric Lens
- Brand
- Edmund Optics
Properties
- Shape
- Circular
- Diameter
- 25 mm
- EFL
- 75 mm
- BFL
- 72.3 mm
- R1
- 59.61 mm
- R2
- 78 mm
Material
- Name
- Germanium
- Dispersion Equation
- Sellmeier
- n (λ)
- 4.024720747638282
- λ
- 4000 nm
- B1
- 0.4886331
- C1
- 1.393959 μm2
- B2
- 14.5142535
- C2
- 0.1626427 μm2
- B3
- 0.0091224
- C3
- 752.19 μm2
68-250 25mm Dia. Germanium Infrared Aspheric Lens; EFL=75mm; NA=0.17 BBAR 3-5µm
This is a high-quality aspheric lens from Edmund Optics, with the catalog number 68-250. It is designed for infrared applications, with a wavelength of 4000 nanometers. The lens is made of germanium burnett, a material known for its excellent optical properties in the infrared spectrum.
The lens has a diameter of 25mm and an effective focal length (EFL) of 75mm, making it suitable for a wide range of applications. The numerical aperture (NA) is 0.17, which indicates the light-gathering capacity of the lens. The lens is coated with BBAR 3-5µm, a broadband anti-reflection coating that enhances transmission and reduces reflections.
The lens geometry is also noteworthy. It has an inner radius of 0mm and an outer radius of 0mm, indicating a circular shape. The thickness at the edge is 2.39mm, and the thickness at the center is 2.8mm. The lens has a front surface with a radius of curvature (R1) of 59.61mm and a back surface with a radius of curvature (R2) of 78mm. The back focal length (BFL) is 72.3mm.
The lens is coated on both the front and back surfaces with edm arcedgermanium35, a specialized coating for germanium lenses. This coating is designed to enhance the performance of the lens in the infrared spectrum.
