1. A waveguide-type image transmission device comprising: a light illumination means having: a light illumination base member made of a light transparent material and transmitting a light beam by multiple reflection on said boundary faces thereof; a first grating pattern formed on a part of a surface of said light illumination base member and diffracting an inputted light beam in a predetermined direction; a second grating pattern provided on another part of the surface of said light illumination base member and diffracting and outputting the light beam transmitted in said light illumination base member in another predetermined direction for illuminating an object to be identified; and an image transmission means having: an image transmission base member made of a transparent material and transmitting a light beam by multiple reflection on the boundary faces thereof; a third grating pattern formed on a part of a surface of said image transmission base member and diffracting an input light beam which is reflected by said object in a predetermined direction; a diffraction lens pattern formed on another part of the surface of said image transmission base member for focusing the light beam which is transmitted in said image transmission base member; and a fourth grating pattern formed on still another part of the surface of said image transmission base member and diffracting and outputting the light beam which is transmitted in said image transmission base member and focused by said diffraction lens pattern in still another predetermined direction.