US5440423A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical illumination instrument
Assignee: NEC Corp
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Filing: 1994-01-10
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Granted: 1995-08-08
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Expires: 2014-01-10
Abstract
Abstract In an optical illumination instrument for use in photolithographic process of manufacturing semiconductor devices, a reflection type homogenizer is composed of an array of paraboloid mirrors of a same size arranged on a same plane.
Inventors
- 👤 Yukio Ogura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:20
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/09; G02B27/0938; G02B27/0977; G02B27/0983; B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/0604; B23K26/067; G02B19/00; G02B19/0004; G02B19/0028; G02B19/0033; G02B19/0047; G02B27/0905; G02B5/00; G02B5/02; G02B5/0205; G02B5/021; G02B5/0215; G02B5/0273; G02B5/0284; G02B5/08; G02B5/10; G03; G03F; G03F7/00; G03F7/70; G03F7/70058; G03F7/702
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
96 words
An optical illumination instrument comprising a reflection type homogenizer composed of an array of paraboloid mirrors and a light beam transformer for transforming a light beam to a suitable size for illuminating said reflection type homogenizer, wherein said light beam transformer comprises a first paraboloid mirror for focusing a parallel light beam received at its focal point, and a second paraboloid mirror with its focal point placed at the focal point of said first paraboloid mirror for reflecting said light beam from said focal point of said second paraboloid mirror to form a parallel light beam.
Claim 2
Dependent Claim
96 words
An optical illumination instrument comprising a reflection type homogenizer composed of an array of paraboloid mirrors and a light beam transformer for transforming a light beam to a suitable size for illuminating said reflection type homogenizer, wherein said light beam transformer comprises a first paraboloid mirror for focusing a parallel light beam received at its focal point, and a second paraboloid mirror with its focal point placed at the focal point of said first paraboloid mirror for reflecting said light beam from said focal point of said second paraboloid mirror to form a parallel light beam.
Claim 3
Dependent Claim
108 words
An optical illumination instrument comprising: a reflection type homogenizer comprising a number of paraboloid mirrors of a same size arranged on a same plane, a light beam transformer composed of a first paraboloid mirror for focusing a parallel light beam at its focal point, and a second paraboloid mirror with its focal point placed at the focal point of said first paraboloid mirror for reflecting a light beam from the focal point of said first paraboloid mirror as a parallel light beam of a size suitable for illuminating said reflection type homogenizer, and an illumination lense for illuminating a reticle by light reflected from said reflection type homogenizer.
Claim 4
Dependent Claim
108 words
An optical illumination instrument comprising: a reflection type homogenizer comprising a number of paraboloid mirrors of a same size arranged on a same plane, a light beam transformer composed of a first paraboloid mirror for focusing a parallel light beam at its focal point, and a second paraboloid mirror with its focal point placed at the focal point of said first paraboloid mirror for reflecting a light beam from the focal point of said first paraboloid mirror as a parallel light beam of a size suitable for illuminating said reflection type homogenizer, and an illumination lense for illuminating a reticle by light reflected from said reflection type homogenizer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-07 | 1999-02-06 | 1999-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-07 | 2003-02-06 | 2003-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-07 | 2007-02-06 | 2007-08-08 | $7700.00 | Window Closed / Lapsed |