(under subclass 201.1) Subject matter having means for illuminating the photocell in accordance with the relative position of the photocell and a pattern, and having means for causing the photocell to follow the edge of the pattern under control of said illumination, or for causing the optical path between pattern and photocell to change, under the control of said illumination, so that the photocell follows the edge of the pattern image.
(1) Note. The edge of the pattern may be either a thick or thin line or the line of demarcation between two areas of different optical properties. The photocell may follow the pattern either by moving spatially or by causing the pattern to move past the photocell while the photocell remains stationary.
SEE OR SEARCH THIS CLASS, SUBCLASS:
548, for optical systems including a web, strand, strip, or sheet and a photocell controlling same.
559.01+, for optical systems, including a web, strand, strip, or sheet and photocell circuit.
