US Patent 7623167 Wavelength component proportion detection apparatus and image-pickup apparatus

A wavelength component proportion detection apparatus is disclosed which is capable of detecting the proportions of the wavelength components under a light source including the visible and infrared wavelength components. The apparatus comprises a color filter, an image-pickup element, an extractor which extracts a color-difference signal from an image-pickup signal, and a detector which detects, on the basis of the extracted color-difference signal, the proportion of a wavelength component in a first infrared wavelength region and the proportion of a wavelength component in a second infrared wavelength region in the light from the light source.