PURPOSE: To improve resolution and to obtain a deeper focus depth by increasing the effective incidence diameter of a first optical integrator to be longer than the diameter of beams which are discharged from a light source part.
CONSTITUTION: An exposure optical system is provided with a first optical integrator 15 for forming a first secondary light source image by applying beams from a laser light source part 4 and a second optical integrator 18 for forming a secondary light source image by applying the light from the first secondary light source image. Then, the effective incidence diameter of the first optical integrator 15 is longer than the diameter of beams which are discharged from the laser light source part 4, thus improving resolution and obtaining a deeper focus depth by obtaining a uniform light intensity distribution even on the incidence pupil of a projection lens without causing the quantity of light to be lost even when there is a relative displacement between the laser light source part 4 and a lighting part.
SUZUKI HITOSHI
YOSHINO TOSHIKAZU
KUWABARA OSAMU
ISHIBASHI YORIYUKI
TOSHIBA CORP