ILLUMINATING DEVICE AND EXPOSURE SYSTEM PROVIDED THEREWITH

PROBLEM TO BE SOLVED: To lessen a lighting device in size by a method wherein a tapered reflector tilted at a prescribed angle with a reference plane is provided to the surface of a shutter on which light is incident. SOLUTION: A shutter 34 possessed of a reference plane Ru generally vertical to the optical axis of illuminating light L and drive means 36 and 38 which enable the shutter 34 to be inserted into the optical axis when the light L is interrupted or to get out of the optical axis when the light L is not interrupted. Tapered reflectors 50a and 50b tilted at a prescribed angle with a reference plane Ru are provided to the surface of the shutter 34 on which light is incident. Two or more pairs of the tapered reflectors 50a and 50b may be formed. It is preferable that the angle of inclination of the tapered reflectors 50a and 50b is set at an angle of 10 deg. to 45 deg. with the reference plane Ru. The tapered reflectors 50a and 50b are formed like a cone in cross section so as to reflect light in two directions.