Image Sensor
The silicon chip that converts light into an electrical signal, forming the digital equivalent of film.
Measured in
mm
In depth
A sensor is an array of light-sensitive wells, each accumulating charge in proportion to the photons that strike it during the exposure. It records only intensity, not colour, so a filter array and subsequent interpolation are required to produce a colour image. Its size, not its pixel count, is the dominant factor in image quality.
Examples in practice
A full-frame sensor gathers about four times the light of a Micro Four Thirds sensor at the same exposure settings.