Concave lens

Bi-concave lenses have a negative focal length and are best used to diverge a converging beam. Bi-concave lenses can diverge a collimated beam to a virtual focus and are commonly used in Galilean-type beam expanders.
Bi-concave lenses with AR coating will increased the transmission of the light for the coating wavelength.
Changchun Yutai optics company can supply double concave lenses in diameter 12.7mm 25.4mm 38.1mm and so on.([email protected])
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