US 6,639,652 B1 · Illumination system for use in exposure apparatus · patentgrep

Loading patent…

Abstract

An illumination system includes an optical system, an optical integrator and a condenser. The optical system collects light from a light source and includes a mirror for reflecting the light. The mirror has an ellipsoidal reflection surface of a shape being out of axial symmetry for defining an aperture of rectangular or semicircular shape as seen in an optical axis direction. The optical integrator produces plural light beams by use of light from the optical system and includes an array of condensing elements having a light entrance surface of rectangular shape as seen in the optical axis direction. A lengthwise direction of the rectangular-shaped or semicircular-shaped aperture of the ellipsoidal reflection surface corresponds to a lengthwise direction of the rectangular-shape light entrance surface of the condensing elements. The condenser illuminates a surface to be illuminated by use of the plural light beams.

Claims45

Dependent claims

An illumination system, comprising:

an optical system for collecting light from a light source, said optical system including a mirror for reflecting the light, said mirror having an ellipsoidal reflection surface of a shape being out of axial symmetry, for defining an aperture of a rectangular or semicircular shape as seen in an optical axis direction;
an optical integrator for producing plural light beams by use of light from said optical system, said optical integrator comprising an array of condensing elements each having a light entrance surface of a rectangular shape as seen in the optical axis direction, wherein a lengthwise direction of the rectangular-shaped or semicircular-shaped aperture of the ellipsoidal reflection surface corresponds to a lengthwise direction of the rectangular-shaped light entrance surface of the condensing element;
and
a condenser for illuminating a surface to be illuminated, by use of the plural light beams.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said segmental elliptical mirror having a shape defined by cutting an elliptical shape along a plane parallel to a line which connects the first and second focal points, said segmental elliptical mirror being operable to reflect only a portion of light from said light source, which is in a solid angle range not greater than 2π, and (ii) a segmental spherical mirror having a curvature center defined at the first focal point position and having a shape defined by cutting a spherical shape along a plane parallel to a line that connects the first and second focal points, said segmental spherical mirror being operable to reflect light from said light source having a solid angle not less than 2π and not being reflected by said segmental elliptical mirror, and to deflect the reflected light toward said light source.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points, said segmental elliptical mirror being operable to reflect only a portion of light from said light source, which is in a solid angle range not greater than 2π, (ii) a segmental paraboloid mirror having a focal point defined at the first focal point position and having a shape defined by cutting a paraboloid shape along a plane parallel to a line which connects the first and second focal points, said segmental paraboloid mirror being operable to reflect light having a solid angle not less than 2π and not being reflected by said segmental elliptical mirror, and to deflect the reflected light in a predetermined direction, and (iii) a plane mirror having a reflection surface perpendicular to said predetermined direction, said plane mirror being operable to deflect light from said paraboloid mirror to turn back the deflected light to said paraboloid mirror.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points, said segmental elliptical mirror being operable to reflect only a portion of light from said light source which is in a solid angle range not greater than 2π, (ii) a first segmental paraboloid mirror having a focal point defined at the first focal point position and having a shape defined at the first focal point position and having a shape defined by cutting a paraboloid shape along a plane parallel to a line which connects the first and second focal points, said first segmental paraboloid mirror being operable to reflect light having a solid angle not less than 2π and not being reflected by said segmental elliptical mirror, and to deflect that reflected light in a direction parallel to the line connecting the first and second focal points, and (iii) a second segmental paraboloid mirror having a focal point defined at the first focal point position and having a shape defined by cutting a paraboloid shape along the plane, said second segmental paraboloid mirror being operable to reflect light having a solid angle not less than 2π and not being reflected by said segmental elliptical mirror, and to deflect that reflected light in a direction parallel to a line which connects the first and second focal points.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a first segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said first segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points, said first segmental elliptical mirror being operable to reflect only a portion of light from said light source which is in a solid angle range not greater than 2π, (ii) a second segmental paraboloid mirror having a first focal point defined at the first focal point position, for collecting light from said light source to a second focal point thereof, said second segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points thereof, said second segmental elliptical mirror being operable to reflect light from said light source which is in a solid angle range not less than 2π, toward the second focal point thereof, and (iii) a hyperboloids mirror having two focal points defined at the first and second focal point positions of the second segmental elliptical mirror, respectively, said hyperboloids mirror being operable to reflect light reflected by said second segmental elliptical mirror and to deflect that reflected light toward said light source.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a first segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said first segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points, said first segmental elliptical mirror being operable to reflect only a portion of light from said light source which is in a solid angle range not greater than 2π, (ii) a second segmental elliptical mirror having a first focal point thereof, said second segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points thereof, said second segmental elliptical mirror being operable to reflect light from said light source which is in a solid angle range not less than 2π, toward the second focal point thereof, and (iii) a spherical mirror having a curvature center defined at the second focal point position of the second segmental elliptical mirror, said spherical mirror being operable to reflect light reflected by said second segmental elliptical mirror and to deflect that reflected light toward said second segmental elliptical mirror.

1 more element

An illumination optical device comprising:

a collective optical system for collecting light from a light source;
and
an illuminating optical system for projecting light from said collective optical system onto a surface to be illuminated,
wherein said collective optical system includes (i) a first segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said first segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line that connects the first and second focal points, said first segmental elliptical mirror being operable to reflect only a portion of light from said light source which is in a solid angle range not greater than 2π, and (ii) a second segmental elliptical mirror having a first focal point defined at the light source position, for collecting light from said light source to a second focal point thereof, said second segmental elliptical mirror having a shape defined by cutting an elliptical mirror shape along a plane parallel to a line which connects the first and second focal points thereof, said second segmental elliptical mirror being operable to reflect light from said light source which is in a solid angle range not less than 2π, toward the second focal point thereof, and also to reflect and deflect light from the second focal point toward said light source.

1 more element

Dependencies are inferred from the claim text.