Colorimetric apparatus and colorimetric method

摘要

In an apparatus including an irradiation unit capable of irradiating a sheet selectively with visible light and ultraviolet light, and a measurement unit which measures a spectral reflectance based on light reflected by the sheet, whether to cause the irradiation unit to emit the ultraviolet light when measuring the spectral reflectance of a patch image printed on the sheet is determined based on the spectral reflectance of a reference image of the color of the sheet that has been measured by the measurement unit which measures a spectral reflectance while the ultraviolet light is emitted.

主权项

1. A colorimetric apparatus comprising:
an irradiation unit configured to irradiate a sheet selectively with visible light and ultraviolet light; a measurement unit configured to measure a spectral reflectance based on light reflected by the sheet; and a determination unit configured to determine, based on a spectral reflectance of a reference on the sheet that is measured by said measurement unit during an emission of the ultraviolet light, whether to cause said irradiation unit to emit the ultraviolet light when measuring a spectral reflectance of each of color patches on the sheet, wherein, said irradiation unit includes a first ultraviolet light source and a second ultraviolet light source having a wavelength different from that of the first ultraviolet light source, and wherein, in a case where the spectral reflectance of the reference contains a wavelength region of visible light, said measurement unit measures each of the color patches on the sheet by the first ultraviolet light source and the second ultraviolet light source respectively.