Specifications:
| Lens Form | Achromatic Doublet Lens | Materials | BK7/SF2 |
| Diameters(mm) | 25.40(+0.0/-0.1) | Effective Focal Length EFL(mm) | 400±1% |
| Back Focal Length BFL(mm) | 396.0 | Coating | 350-650nm AR Coating |
| Surface Quality(S/D) | 60/40 | Irregularity@632.8nm | λ/2 |
| Centration | ≤3 arc min | Center Thickness | 6.0±0.2 |
| Edge Thickness(mm) | 5.5±0.2 | Clear Aperture | >90% |
Dia25.40mm EFL400mm BK7 SF2 Achromatic Doublet Lens 350-650nm AR Coating, Code: 1113-146
An Achromatic Doublet Lens is an optical lens component consisting of one lens made from crown glass of positive, minor refractive index and one lens made from flint glass of negative, greater refractive index cemented together. The purpose of an achromatic doublet lens is to mitigate chromatic aberration and stabilize the shift of focal lengths between designed wavelengths.
Hangzhou Shalom EO provides off-the-shelf achromatic doublet lenses with a sufficing selection of focal lengths (positive 7.5mm to 1000mm, negative -100mm to - 20mm) and standardized diameters that are compatible with most optic sets. Three options of anti- reflection coatings from visible to infrared wavelength range are accessible: 350-650nm, 650- 1050nm, and 1050-1580nm.
