1) Exposure meter 2) Light meter 3) Photometer 
cytophotometer 1. An instrument that uses the variations in light intensity produced by stained cell cytoplasm to identify and locate chemical compounds within cells. 2. A photometer that can be used to locate and identify chemical compounds in a cell by measuring the intensity of the light that passes through stained sections of the cytoplasm.
noun a photometer that can be used to locate and identify chemical compounds in a cell by measuring the intensity of the light that passes through stained sections of the cytoplasm
an instrument for examining cells by determining the intensity or wavelengths of light transmitted through them.