IMAGE READER

PURPOSE:To prevent reflected light from a manuscript area readable from one picture element from entering other picture elements which exclude the reflected light and enhance the resolution (MTF) of an image sensor in a picture reader which integrates a light emitting element with a contact image sensor. CONSTITUTION:A photodetector 100 formed on a first substrate 10 and a light emitting element formed on a second substrate are laid out so that they may be opposed to each other with a transparent layer 300 clamped and light from the light emitting element 200 is applied to the surface of a source manuscript 400 laid out on the opposite side of the light emitting element 100 of the second substrate 20 and the reflected light is arranged to enter the light receiving element 100, thereby constituting an image reader. Since the transparent layer 300 is formed with a medium whose refractive index is smaller than that of the second substrate 20, the reflected light from the source manuscript 400, which is going to enter the transparent layer 300 at an incident angle which exceeds a critical angle which can be determined with a ratio of a refractive index between the second substrate 20 and the transparent layer 300, is totally reflected on the top of the transparent layer 300 and prevented from entering the light emitting element 100.