selenium photocell การใช้

• Kurt Kramer introduced a selenium photocell to medical research.
• By the mid-1930s, selenium photocells controlled assembly lines, elevators and looms.
• The first used an array of selenium photocells and wires to transmit an image to an array of light, which were then used to expose a piece of photographic paper.
• The use of a selenium photocell to select the shutter speeds and aperture let novices use the camera as a " point & shoot ", with good results obtained most of the time.