Photometric measurement, or photometry, is a technique that can be used to measure the concentration of organic and inorganic compounds in solution by determining the absorbance of specific wavelengths of light. …

Photometric range refers to the range of light waves from ultraviolet to infrared wavelengths. The photometric range spans both the visible spectrum of color and wavelengths invisible to the naked eye.

A goniophotometer is a photometric device that is used to measure the perceived power of a light source at different angles. It is mostly used to test the luminous flux of directed light sources such as LED and automotive headlights.

A light meter, a specific type of photometer, is used to measure the amount of light present. In photography, light meters help the photographer determine the correct shutter speed and f-number selection for the desired exposure.

Photometric testing includes testing any light emitting device such as LEDs, lamps, signs, luminaires, and more for product performance in an effort to ensure the device meets regulatory demands. Photometric testing also includes safety and developmental testing for new and existing efficient lighting products.

As a basic principle, photometers examine how light interacts with reflective materials. Some instruments are used to observe how light absorbs and/or reflects wavelengths. Other instruments measure light by converting light into an electrical current and then measuring the electrical current produced by the light.

Radiometry is the measurement of optical radiation, which is electromagnetic radiation in the frequency range between 3 x 1011 Hz and 3 x 1016 Hz. Photometry is the measurement of light, which is defined as electromagnetic radiation detectable by the human eye.