Photosensitive measuring system which converts a physical to an electrical quantity

Claim 1

A GAUGING SYSTEM COMPRISING, A STATIONARY GRATING HAVING ALTERNATE OPAQUE AND TRANSPARENT BANDS, SAID STATIONARY GRATING HAVING FIRST AND SECOND SECTIONS; A MOVABLE GRATING HAVING ALTERNATE OPAQUE AND TRANSPARENT BANDS, THE BANDS OF ONE OF SAID GRATINGS BEING ARRANGED SUCH THAT AS SAID MOVABLE GRATING MOVES WITH RESPECT TO SAID STATIONARY GRATING THE OPAQUE BANDS OF SAID MOVABLE GRATING MOVE TOWARD ALIGNMENT WITH THE OPAQUE BANDS OF ONE OF SAID STATIONARY GRATING SECTIONS AND TOWARD ALIGNMENT WITH THE TRANSPARENT BANDS OF THE OTHER OF SAID STATIONARY GRATING SECTIONS; A NORMALLY SYMMETRICAL RELAXATION OSCILLATOR COMPRISING A PAIR OF SWITCHING DEVICES CONNECTABLE TO A SOURCE OF UNIDIRECTIONAL POTENTIAL; EACH OF SAID SWITCHING DEVICES HAVING A TIMING CIRCUIT CONTROLLING THE CONDUCTING TIME OF A RESPECTIVE SWITCHING DEVICE; PHOTOSENSITIVE ELEMENTS IN EACH OF SAID TIMING CIRCUITS HAVING AN EFFECTIVE RESISTANCE VALUE VARIABLE IN RESPONSE TO THE INTENSITY OF LIGHT INCIDENT THEREUPON, EACH OF SAID PHOTOSENSITIVE ELEMENTS BEING POSITIONED BEHIND ONE OF SAID STATIONARY GRATING SECTIONS WHEREBY LIGHT TRANSMITTED THROUGH SAID GRATINGS AND INCIDENT UPON SAID PHOTO-SENSITIVE ELEMENTS VARIES THE EFFECTIVE RESISTANCE OF SAID PHOTOSENSITIVE ELEMENTS INVERSELY WITH MOVEMENT OF SAID MOVABLE GRATING, THE EFFECTIVE RESISTANCE OF EACH OF SAID PHOTO-SENSITIVE ELEMENTS CONTROLLING THE TIME OF CONDUCTION OF AN ASSOCIATED ONE OF SAID SWITCHING DEVICES; AND MEANS FOR AVERAGING THE CONDUCTING TIMES OF SAID SWITCHING DEVICES.