The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jan. 11, 1977

Filed:

Dec. 10, 1971
Applicant:
Inventor:

Michito Amma, Tokyo, JA;

Assignee:

Gakken Co. Ltd., Tokyo, JA;

Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
B03B / ;
U.S. Cl.
CPC ...
353 70 ; 353D / ;
Abstract

In a system of overhead projection there is provided a horizontal stage on which is to be placed an object to be imaged. Means for illuminating the object is mounted below the stage at an angle thereto, while a projection lens system is installed above the stage and parallel thereto, in such a position that the axis of the light from the illumination means passes at an angle through its center. A mirror mounted above the lens system projects the undistorted image of the object onto a vertical screen. In another system of overhead projection based on the same principles, the stage and the projection lens system are inclined relative to the illumination means while themselves kept parallel to each other. The axis of the light from the illumination means in this instance extends vertically upwardly and passes at an angle through the center of the lens system. There are further disclosed herein some overhead projectors constructed in accordance with these systems of the invention.


Find Patent Forward Citations

Amma, Michito. (1977). System and device for overhead projection (U.S. Patent No. 4002408). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4002408

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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