Edmund Optics has launched its Techspec Aspherised Achromats, which bridge the gap between colour-corrected achromats and spherical aberration corrected aspheres. Typical applications include: fibre optic focusing or collimation, condensing systems, image relay, inspection, scanning, beam expanders, and high numerical aperture imaging.
Achromatic lenses typically consist of cemented assembly of a low index and high index lens, matched for their ability to reduce chromatic aberration, but not necessarily matched to correct for focusing aberrations inherent in spherical lenses. Meanwhile, aspheric lenses excel at correcting spherical aberrations, but are not capable of addressing chromatic aberrations. Techspec Aspherized Achromats correct for both types of aberrations.
The second surface of the doublet lens is fused to a moulded polymer aspheric surface. This surface reduces the wavefront errors present in typical achromats while boosting numerical aperture. Nine versions of the lens are available, with diameters of 9.0, 12.5, or 25mm, and effective focal lengths ranging from 12 to 50mm.