Photometers are devices used to measure the intensity of light. They come in various forms and can be classified into categories such as colorimeters, spectrophotometers, and radiometers. Synonyms for photometers might include light meters or brightness gauges, which measure the amount or intensity of light. Another synonym might be lux meters, which measure the amount of light illuminating a surface. In scientific circles, photometers might also be called radiometers, which measure radiant energy from optical sources, or photodetectors, which can detect and sometimes quantify the amount of light detected. Regardless of the specific synonym, all photometers serve the same purpose - to measure light intensity.