These lenses consist of two optical elements, usually of crown and flint glass types, cemented together to form an achromatic doublet. Most often, the crown lens is a biconvex positive lens. Due to the difference in refractive indices, chromatic aberration with respect to two selected wavelengths has been corrected. The lenses have been corrected for on-axis spherical aberration as well. Achromatic doublets are used as telescope objectives, eye loupes, magnifying glasses and eyepieces. Achromatic doublets have also been used to focus and manipulate laser beams because their image quality is superior to single lenses.
| Diameter | Dia. Tolerance | CT Tolerance | Centering | Irregularity | Surface Quality | Bevel |
| 6.00-25.00 | +0.00 / -0.10 | ±0.2 | < 3 minutes | 0.5 Waves | 40-20 | 0.25 x 45° |
| 25.01 - 50.00 | +0.00 / -0.10 | ±0.2 | < 3 minutes | 0.5 Waves | 60-40 | 0.50 x 45° |
| >50.00 | +0.05 / -0.10 | ±0.2 | 3 - 5 arc min. | 1.0 Waves | 60-40 | 0.50 x 45° |
| Dimensions | MM | |||||
| Clear Aperture | CA >= 90% of Diameter | |||||
| Coating | 1/4wave MgF2 @ 550nm (See Coating Chart for Available Options) | |||||
| Design Wavelength | 587.6nm | |||||
| Focal Length Tolerance | ±2% | |||||
| Edge Thickness | Reference | |||||
| * All dimensions are in mm | ||||||