1. An endoscope apparatus comprising: an endoscope including an elongated insertable portion, a light guide extended through said elongated insertable portion and transmitting illuminating light, an objective optical system attached to a distal end of said insertable portion and forming an image of an object, an image guide extended through said insertable portion and having an incident end surface at a focal plane of said objective optical system, said image guide transmitting an optical image, and an eye-contact portion opposing a light emitting end of said image guide; a video converter mounted on said eye-contact portion, said video converter including an image forming optical system forming the optical image transmitted through said image guide, and a solid-state imaging device disposed at a position where said optical image is formed by said image forming optical system; a signal processing means for processing output signals from said solid-state imaging device to form a video signal; display means for displaying an object image by the video signal output from said signal processing means; a light source unit supplying illuminating light to said light guide; and a light control device including level judging means for determining whether output signals, from a plurality of pixels on said solid-state imaging device, exceed a predetermined level, correction signal generating means for generating, in accordance with an output signal from said level judging means, a photo-sensing area correction signal corresponding to an actual imaging area on said solid-state imaging device on which an end area of said image guide is actually formed, and light control signal generating means for generating a light control means for controlling the illuminating light output from said light source unit by dividing the output signals from said solid-state imaging device by said correction signal.