object-glass
(ˈɒbdʒɪktglɑːs, -æ-)
[object n. 3.]
The lens or combination of lenses in a telescope, microscope, or other optical instrument, which is situated nearest to the object, and thus receives the rays of light directly from it. (Cf. eye-glass 4.)
| 1665 R. Hooke Microgr. ii. 4, I..plac'd it between the Object-glass and the light. 1784 Herschel in Phil. Trans. LXXV. 44 Turning or unscrewing the object-glass or speculum a little. 1829 Nat. Philos. I. Optics x. 27 (U.K.S.) The triple achromatic object-glass..consists of..a concave flint glass lens placed between two convex lenses of crown glass. 1839 G. Bird Nat. Phil. 390 The magnifying power of these telescopes is found by dividing the focal length of the object-glass by that of the eye-glass. |