Lens

(lenz) [L., a lentil]. I. A piece of gla or crystal for the refraction of rays of light. 2. The crystalline lens of the eye. L., Achromatic. See Achromatic. L., Apochromatic. See Apochromatic. L., Biconcave (negative or minus (— ) lens), a thick edged lens having concave spheric surfaces upon its opposite sides; it is used in spectacles to correct myopia. L., ch423.xhtml b 358