Densitometer

Patent Pending A densitometer is a device that measures the degree of darkness (the optical density) of a photographic or semitransparent material or of a reflecting surface.[1] The densitometer is basically a light source aimed at a photoelectric cell.[2] It determines the density of a sample placed between the light source and the photoeectric cell from differences in the readings.[3] Modern densitometers have the same components, but also have electronic integrated circuitry for better reading.