The Sensitivity of Selenium Cells

Abstract

THE selenium cell, as a light-sensitive element, has always been held to have the inherent drawbacks of inertia and lag, and therefore to respond too sluggishly to changes in light intensity, and to return to its normal low conductivity much too slowly when the illumination to which it has been subjected is cut off. Several forms of photometer are now in use in which selenium or photo-electric cells are employed, and were selenium more certain and more prompt in action it would offer certain advantages over the photo-electric cell.