Method and apparatus for illuminating a surface using a projection imaging apparatus

An illumination optical system for a projection imaging apparatus, comprising:

• a light source that emits an illumination light having a predetermined wavelength;
• a wavefront dividing type optical integrator that forms a substantially planar light source;
• a condenser that guides the light from the wavefront dividing type optical integrator into a mask surface or a mask conjugate surface, in a superposing manner;
• and
• a light beam converter, disposed between said light source and said wavefront dividing type optical integrator, having a diffractive optical device that diffracts the light from the light source and divides the wavefront of the light from the light source, and an optical device that converts the light from the light source into light having a predetermined sectional shape at a predetermined plane,
• wherein an entrance surface of said wavefront dividing type optical integrator is substantially disposed in said predetermined plane, and
• wherein the predetermined sectional shape at the predetermined plane comprising a sectional shape differs in light intensity between a central region of said predetermined plane and a peripheral region of said predetermined plane and the sectional shape with a nearly even light intensity distribution.

An illumination optical system for a projection imaging apparatus, comprising:

• a light source that emits illumination light;
• a light beam converter having a diffractive optical device that diffracts the light from the light source, and converts the light into light having a predetermined sectional shape at a predetermined plane;
• an optical integrator that forms a substantially planar light source based on light from the light beam converter;
• and
• an optical system that guides light from the optical integrator;
• wherein said diffractive optical device is disposed in an enclosed space formed by a pair of covering optical members.

An illumination optical system for a scanning projection imaging apparatus, comprising:

• a light source that emits an illumination light;
• a diffractive optical device that diffracts the light from the light source;
• and
• an optical integrator that forms a substantially planar light source based on light from the diffractive optical device,
• wherein said optical integrator includes a plurality of optical elements having a first direction corresponding to a scanning direction, a second dimension crossing the first direction, a first dimension along the first direction and a second direction along the second direction, the first direction differs from the second direction,
• wherein said diffractive optical device forms an illumination region on said plurality of optical elements, and
• wherein said illumination region has an edge that inclines in a direction corresponding to the scanning direction.