using movable reflectors to alter length of light-path

Full Title

Focusing arrangements of general interest for cameras, projectors or printers > adjusting position of image plane without moving lens > using movable reflectors to alter length of light-path

Classification Context

Section:

PHYSICS

Class:

PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY

Subclass:

APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR