Patent ID: 8488030

Claim:
A method comprising: separating an electromagnetic wave into a plurality of wavelength components by a diffraction effect, the diffraction effect resulting from the electromagnetic wave passing through openings of a diffraction grating in a semiconductor device, the diffraction grating being parallel to an incidence surface of a substrate of the semiconductor device, the diffraction grating including (i) a plurality of first scatterers, (ii) a plurality of second scatterers between the first scatterers and the incidence surface, (iii) a plurality of third scatterers between the second scatterers and the incidence surface; directing the plurality of wavelength components onto corresponding positions on the incidence surface; and detecting the wavelength components directed out of the diffraction grating, wherein, the first, second and third scatterers in the diffraction grating are configured such as to separate the electromagnetic wave into the plurality of wavelength components and direct the wavelength components onto the corresponding positions on the incidence surface, the semiconductor device further includes a plurality of photodiode groups on the incident surface side that are positioned such as to receive the wavelength components directed out of the diffraction grating, and the photodiode groups are used in the detecting step, each of the photodiode groups including a plurality of photoelectric conversion elements that (i) each detect a respective wavelength component corresponding to one of primary colors of red, green, and blue, and (ii) output a respective signal charge for conversion into a signal corresponding to the detected wavelength component, photoelectric conversion elements of adjacent photodiode groups being arranged in a transverse direction of the substrate to detect the colors in the order of blue, green, red, green, blue, green, red, green, blue, . . . .