04386833 is referenced by 5 patents and cites 4 patents.

An epi-illumination type projection device for forming a projected image of an object comprises a body having a screen, first and second projection lens means alternately mounted at a predetermined location on the body to form different projected images on the screen, and an illuminating system having a light source and a main condenser lens provided in the body to supply an illuminating light to the object through the projection lens means when each of the projection lens means is positioned at said predetermined location. Each of the first and second projection lens means has an engaging surface engaged with the body at said predetermined location, a beam splitter disposed obliquely with respect to the optical axis of the projection lens means, a convergent lens group provided on that side of the beam splitter which is adjacent to the object, and an auxiliary condenser lens provided laterally of the beam splitter. The distance between the position whereat the beam splitter of the first projection lens intersects the optical axis and the engaging surface of the first projection lens means is equal to the distance between the position whereat the beam splitter of the second projection lens means intersects the optical axis and the engaging surface of the second projection lens means.

Title
Epi-illumination type projection device
Application Number
6/272760
Publication Number
4386833
Application Date
June 11, 1981
Publication Date
June 7, 1983
Inventor
Hideo Hirose
Tokyo
JP
Agent
Fitzpatrick Cella Harper & Scinto
Assignee
Nippon Kogaku
JP
IPC
G03B 3/02
G03B 21/06
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