Hologram color filter with alignment mark and alignment method

摘要

The present invention provides a hologram color filter having a drastically decreased dependence of diffraction efficiency on wavelength and well corrected for a color balance among the three colors R, G and B comprising an array of converging element holograms (5'), each of which enables white light incident at a given angle (&thetas;) with respect to a normal line of a hologram recorded surface thereof to be spectroscopically separated by wavelength dispersion in a direction substantially along the hologram recorded surface, wherein the converging element holograms (5') have each a plurality of hologram pieces (51 and 52) superposed on each other or multi-recorded therein, which, with respect to the white light (3) incident at the given angle(&thetas;), have substantially identical spatial wavelength distributions of wavelength dispersion and different peak wavelengths of diffraction efficiency. <IMAGE>