1. A method of recording a color image on a recording medium by applying a plurality of laser beams modulated by color image signals representative of mutually differently colored images, respectively, simultaneously to a plurality of photosensitive bodies, respectively, to form latent images thereon which correspond respectively to the color image signals, developing the latent images into mutually differently colored visible images, respectively, and transferring and fixing the visible images to the recording medium, said method comprising the steps of: providing a hologram disk comprising a circular transparent substrate and a plurality of optically equivalent hologram gratings on a surface of said circular transparent substrate in a single annular pattern; applying said modulated laser beams to said hologram disk at mutually different positions thereon, each of which is determined by the angles defined by the equations given below: ##EQU2## where .alpha..sub.1 is an angle by which the position is displaced from a beam line on the hologram disk, .alpha. is an angle subtended by one sector-shaped hologram grating, .theta..sub.s is the entire angle in which the laser beam is scanned by the hologram disk, .theta..sub.1 is the angle in which the laser beam is scanned above an optical axis passing through said position, and .theta..sub.2 is the angle in which the laser beam is scanned above the optical axis; and rotating said hologram disk to deflect said laser beams simultaneously.