85-984 25 mm Dia. N-LAK22/N-SF6 Achromatic Doublet; EFL=50mm NIR II 750-1550nm
- Type
- Lens
- Subtype
- Multiplets
- Brand
- Edmund Optics
Properties
- Shape
- Circular
- Diameter
- 25 mm
- EFL
- 50 mm
- R1
- 31.69 mm
- R2
- -28.45 mm
Material 1
- Name
- N-LAK22
- Dispersion Equation
- Sellmeier
- n (λ)
- 1.6536179449828925
- λ
- 550 nm
- B1
- 1.14229781
- C1
- 0.00585778594 μm2
- B2
- 0.535138441
- C2
- 0.0198546147 μm2
- B3
- 1.04088385
- C3
- 100.834017 μm2
Material 2
- Name
- N-SF6
- Dispersion Equation
- Sellmeier
- n (λ)
- 1.811866267147773
- λ
- 550 nm
- B1
- 1.77931763
- C1
- 0.0133714182 μm2
- B2
- 0.338149866
- C2
- 0.0617533621 μm2
- B3
- 2.08734474
- C3
- 174.01759 μm2
85-984 25 mm Dia. N-LAK22/N-SF6 Achromatic Doublet; EFL=50mm NIR II 750-1550nm
The 85-984 is a high-quality achromatic doublet lens, boasting a 25 mm diameter and a focal length of 50 mm, specifically designed for use in the near-infrared (NIR) spectrum, covering the wavelength range of 750-1550nm. This lens is sourced from the renowned optical vendor, Edmund Optics, and is a part of their extensive catalog.
The lens is constructed from two types of Schott glass, N-LAK22 and N-SF6, which are carefully selected to minimize chromatic aberration, a common issue in optical systems. The geometry of the lens is meticulously designed, with an inner radius of 0 and an outer radius of 0, ensuring optimal light transmission and focus. The lens has a thickness of 8.94mm at the edge, reducing vignetting and ensuring a wider field of view.
The lens features a robust coating on both the front and back surfaces. This coating, identified as 'edm nir-ii std curve', is specifically designed for use in the NIR spectrum, enhancing the lens's transmission and reducing unwanted reflections. The center thickness of the lens is 8mm, with an 'a' value of 4, which contributes to its overall optical performance and durability.
