← Back to Patent Explorer
US4683524A Expired / Lapsed US ⏱️ 0.0 years remaining

Illumination apparatus

Assignee: Canon Inc
•
Filing: 1986-10-16
•
Granted: 1987-07-28
•
Expires: 2006-10-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An illumination apparatus for illuminating a surface, having formed thereon a pattern, to transfer the pattern onto a semiconductor wafer. The apparatus includes an elliptic mirror for forming an image of a light source, an imaging system for re-imaging the image of the light source, formed by the elliptical mirror, while causing a curvature of field, a multi-beam generating system disposed relative to the imaging system so that the optimum focus located at the off-axis position of the imaging system is coincident with an input surface of the multi-beam generating system, and a collimator for directing to the pattern surface a number of discrete light beams generated by the multi-beam generating system to illuminate the pattern surface. Whereby a uniform intensity distribution of the light illuminating the pattern surface and a high light-collecting efficiency are assured.

Inventors

  • 👤 Masakatsu Ohta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 06:39
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70058

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 100 words
An illumination apparatus, comprising: a light source; an elliptical mirror for forming an image of said light source; an imaging system for re-imaging the image formed by said elliptical mirror, while causing a curvature of field; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 2
Dependent Claim 100 words
An illumination apparatus, comprising: a light source; an elliptical mirror for forming an image of said light source; an imaging system for re-imaging the image formed by said elliptical mirror, while causing a curvature of field; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 3
Dependent Claim 30 words
An apparatus according to claim 1, wherein an optimum focus point at an off-axis position of said imaging system is located on said input surface of said multi-beam generting system.
Claim 4
Dependent Claim 35 words
An apparatus according to claim 2, wherein the optimum focus point at the off-axis position of said imaging system is located at the outermost off-axis portion on said input surface of said multi-beam generating system.
Claim 5
Independent Claim 84 words
An apparatus, comprising: a light source; an imaging system for forming an image of said light source, while causing a curvature of field; a multi-beam generating system for generating, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed at an optimum focus point at an off-axis position of said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 6
Independent Claim 84 words
An apparatus, comprising: a light source; an imaging system for forming an image of said light source, while causing a curvature of field; a multi-beam generating system for generating, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed at an optimum focus point at an off-axis position of said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 7
Dependent Claim 35 words
An apparatus according to claim 4, wherein the outermost off-axis portion of said input surface of said multi-beam generating system is coincident with the optimum focus point at the off-axis position of said imaging system.
Claim 8
Dependent Claim 98 words
An illumination apparatus, comprising: a light source; an elliptical mirror for forming an image of said light source; an imaging system for re-imaging, in a predetermined state, the image formed by said elliptical mirror; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 9
Dependent Claim 98 words
An illumination apparatus, comprising: a light source; an elliptical mirror for forming an image of said light source; an imaging system for re-imaging, in a predetermined state, the image formed by said elliptical mirror; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and a collimating system for collimating each of the discrete light beams emerging from said multi-beam generating system.
Claim 10
Dependent Claim 31 words
An apparatus according to claim 6, wherein said imaging system is effective to define, between an on-axis portion and an off-axis portion, optimum focus positions which are displaced from each other.
Claim 11
Dependent Claim 97 words
An illumination apparatus for illuminating a plane, said apparatus comprising: a light source; an imaging system for forming an image of said light source, while causing a curvature of field; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and optical means for directing each of the light beams from said multi-beam generating system to the plane to be illuminated.
Claim 12
Dependent Claim 97 words
An illumination apparatus for illuminating a plane, said apparatus comprising: a light source; an imaging system for forming an image of said light source, while causing a curvature of field; a multi-beam generating system for producing, from a light beam emitted from said light source, a number of discrete light beams, said multi-beam generating system having an input surface disposed in a predetermined relation to the image of said light source formed by said imaging system; and optical means for directing each of the light beams from said multi-beam generating system to the plane to be illuminated.

References Cited (Backward Citations)

US3795446A Cited
US3815493A Cited
US3988066A Cited
US3941475A Cited
US4023904A Cited
US3981590A Cited
US4241392A Cited
US4375315A Cited
JPS56813A Cited
US4441817A Cited
US4523806A Cited
US4497013A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-07-27 1991-01-26 1991-07-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-07-27 1995-01-26 1995-07-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-07-27 1999-01-26 1999-07-28 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag