PURPOSE: To manufacture a volume hologram filter having desired plural diffraction characteristics by an exposure of once by selecting a combination of plural filters placed in front of a laser so as to obtain a desired wavelength characteristic.

CONSTITUTION: When a laser 1 is oscillated, its laser light transmits through filters 2-1W2-n, and becomes an optical wave having (n) pieces of peaks in accordance with a transmission characteristic of the filters 2-1W2-n. This optical wave is divided into two by a beam splitter 3, reflected by reflecting mirrors 6, 7, and thereafter, causes an interference at a position of a DCG dry plate 8, and an interference fringe 10 arranged in the thickness direction of a photosensitive material layer 9 is generated. In this way, when this DCG dry plate 8 is developed after executing an exposure, a difference of a refractive index is generated in a part where the interference fringe 10 is existed and a part where it is not existed, and a Ripman type hologram of a phase type is obtained. That is to say, by changing a combination of the filters 2-1W2-n, a volume hologram filter having various wavelength characteristics can be manufactured.