Dual power microscope

Claim 2

A microscope haviNg, in alignment along an optical axis: a. a stage and relay assembly comprising a specimen stage, relay lens means and mechanical linkage means for disposing said relay lens means in fixed position relative to said specimen stage; b. an eyepiece and objective assembly comprising objective lens means, eyepiece lens means and mechanical linkage means for disposing said eyepiece lens means in fixed position relative to said objective lens means; and c. base, slide and housing means for slidably and coaxially mounting said two assemblies, with said relay lens means disposed between said objective lens means and said eyepiece lens means, for relative motion along said axis through an excursion, said excursion defining at least two positions of optical cooperation among said objective lens means, said relay lens means, said eyepiece lens means and said specimen stage, one for low magnification viewing and one for high magnification viewing of a specimen on said stage.

Claim 3

The microscope of claim 1 wherein said objective lens means has a focal length FA and said relay lens means has a focal length FB, measurements along said optical axis are taken from said objective lens means positive toward the image side, low magnification conditions are designated by small case letters, high magnification conditions are designated by large case letters; D1, d1 represent the object distances; T, t represent the separations of the objective lens means from said relay lens means; D2, d2 represent the separation of the relay lens means from the eyepiece focal plane; K, k represent the distance from the object plane to the eyepiece focal plane; C represents the length of said excursion measured in the direction of the image; M, m represent the degree of magnification of a specimen in the object plane measured in the eyepiece focal plane; a (1-m)2/m; Q d1 + t - d2; R (FA + FB + d1 - d2)t - (FA + d2)d1 - (FA - d2)FB; t 1/2 ( k + or - Square Root k2 - 4 FA FB a - 4k(FA + FB) ); d1 - FA ( k - t(1-m) )/FA (1-m) + m t ; d2 k + d1 - t; C -Q + or - Square Root Q2 - 4R/2; M (FA/D1 + FA) X (FB - D2/FB); D1 d1 + C; D2 d2 - C; K k - C; and T K + D1 - D2.