COLOR MEASURING APPARATUS

PURPOSE:To process a signal at a good S/N ratio and to correctly measure a color by a method wherein, when a fluorescence-cut filter is inserted and light of an object to be measured does not contain fluorescence, a dynamic range is narrowed. CONSTITUTION:The dynamic range (DR) of an A/D converter 18 is set at 200%, and an object 12 to be measured is irradiated with a light source 11. The light (transmitted light) is spectrum-decomposed by a slit 15 and a spectral element 16, light at a prescribed wavelength is received by a detector 17, and it is converted (quantized) into digital data by the A/D converter 18. An operation and control part 20 to which the digital data has been inputted processes the data, and it decides a color. At this time, when the light contains fluorescence, the DR is set as it is, a wavelength region in which its intensity has been increased by the fluorescence is quantized precisely, and the color is decided correctly. When the light excluding the fluorescence is to be measured, a fluorescence-cut filter 13 is inserted between the object 12 to be measured and the slit 15, the control part 20 reduces the DR to 100% at a point of time when a filter sensor 14 detects it. Thereby, an S/N ratio is enhanced in an A/D conversion, and the color can be measured precisely.