Achromatic lens is a closely spaced and often cemented, combination of positive and negative elements of differing refractive index. These elements are chosen so that the chromatic aberration is eliminated at two distant and well-separated wavelengths. These lenses are made of BK7, fused silica and CaF2 or other equivalent material. Special focusing systems can be designed by our engineers upon request.
| MATERIALS | ILLUSTRATION | PROPERTIES AND APPLICATIONS | |
| ACHROMATIC LENS | Crown glass and flint glass | | These lenses have considerably reduced values of spherical aberrations. Best used to replace single components where performance must be improved. |
| ATTRIBUTE | SPECIFICATIONS |
| DIAMETER SIZE | smallest 3 mm |
| DIAMETER TOLERANCE | +0.0, -0.1mm |
| PARALLEL FOCAL LENGTH TOLERANCE | ±2% |
| CENTRATION | 5 arc minutes |
| CLEAR APERTURE | >90% |
| SURFACE FIGURE: POWER(N) | <3 fringes |
| SURFACE FIGURE: IRREGULARITY(N) | <0.5 fringe |
| SURFACE QUALITY | 40/20 scratch and dig |
| BEVEL | < 0.2 mm x 45° |
| COATING | With AR coating on outside surfaces |
