Variable photosensitive semiconductor device having a graduatingly different operable surface area

Claim 1

IN A PHOTOSENSITIVE DEVICE COMPRISING A SEMICONDUCTOR BODY HAVING A SURFACE, A FIRST PORTION OF SAID BODY ETENDING AWAY FROM SAID SURFACE AND BEING OF A FIRST SEMICONDUCTOR TYPE, A SECOND PORTION OF SAID BODY BEING GENERALLY SPACED FROM SAID SURFACE BY SAID FIRST PORTION AND BEING OF A SECOND SEMICONDUCTOR TYPE, AN AREA JUNCTION BEING DEFINED BETWEEN SAID FIRST AND SECOND BODY PORTIONS, THE SPACING BETWEEN A PART OF SAID SURFACE AND AT LEAST A PART OF SAID AREA JUNCTION BEING WITHIN THE LIMITS OF PHOTOSENSITIVITY, THEREBY TO DEFINE A PHOTOSENSITIVE SECTION, SAID PART OF SAID SURFACE DEFINING AN OPERATIVE SURFACE AREA ON WHICH LIGHT IS ADAPTED TO IMPINGE, THEREBY TO VARY THE ELECTRICAL CHARACTERISTICS OF SAID DEVICE; THE IMPROVEMENT WHICH COMPRISES SAID OPERATIVE SURFACE AREA BEING OF APPRECIABLE EXTENT SUCH THAT LIGHT CAN BE SELECTIVELY DIRECTED TO DIFFERENT SECTIONS THEREOF, AND MEANS FOR RENDERING THE PHOTOELECTRIC SENSITIVITY OF SAID DEVICE GRADUATINGLY DIFFERENT AT SAID DIFFERENT SECTIONS OF SAID OPERATIVE SURFACE AREA, SAID MEANS COMPRISING SAID DIFFERENT SECTIONS OF SAID OPERATIVE AREA WITHIN SAID PHOTOSENSITIVE SECTION BEING SPACED FROM SECTIONS OF SAID AREA JUNCTION THEREOPPOSITE BY DIFFERENT DISTANCES WITHIN THE LIMITS OF PHOTOSENSITIVITY, SAID SECOND BODY PORTION EXTENDING COMPLETELY TO SAID OPERATIVE AREA OVER A FRACTION ONLY OF SAID AREA, THEREBY TO RENDER SAID FRACTION OF SAID OPERATIVE AREA NON-PHOTOSENSITIVE WHILE LEAVING THE REMAINDER OF SAID OPERATIVE AREA PHOTOSENSITIVE.