Bi-concave lens element DCV

BK7UV

* Diameter (metric): 12,5 - 25,0 mm * Diameter (imperial): 0.5 - 1 inch * Diameters up to 4 inch available on request * Focal length from -12,5 mm to -250 mm Bi-Concave (Double Concave) have negative focal lengths and diverge collimated incident light. DCV lenses form only virtual images which are seen through the lens. They minimize spherical aberration, coma and distortion at unit conjugate ratio. These lenses are symmetrical with equal radii on both sides. Biconcave lenses are often used to expand light beams or to increase focal lengths in optical systems, and are normally used in combination with other lenses. Among the many devices utilising biconcave lenses are laser beam expanders, optical character readers, viewers and projection systems. A variety of anti-reflection coatings is available for these lenses.