Edmund Optics Inc. Aspheric Lens 27mm Diameter x 13mm FL NT43-987

Used primarily in high efficiency illumination systems, aspheric condensers offer superior aberration correction. We provide these in low f/#s for higher light gathering efficiency in condensing, projecting, and other illumination applications. Our aspheric lenses are ground and polished on the plano side and precision molded on the aspheric side. Note: Lenses are sold individually (not in sets of two).Application Note: Aspheric condenser lenses efficiently correct for spherical aberrations and coma. For this reason, one aspheric condenser can replace a multiple spherical element design. This replacement reduces the number of back reflections and ultimately yields higher transmission. They are usually mounted in pairs, so that their convex surfaces are nearly in contact. These systems require lenses somewhat larger in diameter than the diagonal measurement of the slide or target projected. Refer to the chart for approximate lens size.Note: The f/# is a calculated value based on EFL/Dia.