US3853398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mask pattern printing device
Assignee: Canon Inc
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Filing: 1973-06-04
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Granted: 1974-12-10
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Expires: 1993-06-04
Abstract
Abstract In the mask pattern printing device disclosed an optical system forms an illuminating beam and directs the illuminating beam through a mask onto a photosensitive surface and thereby forms a reflected beam. An observation system for aligning the mask image with the photosensitive surface is composed of a polarizer, a delay for delaying the polarized light one-quarter wavelength, and an analyzer. The observation system locates the polarizer in the illuminating beam before it reaches the mask to polarize the beam passing through the mask and the delay between the mask and the surface while the analyzer protrudes into the reflected beam for observation. Preferably the observation system is capable of moving at least the analyzer and the polarizer into and out of the illuminating beam. The observation system eliminates harmful reflected light from the mask and observes only the reflected light from the photosensitive plate.
Inventors
- 👤 I Kano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:50
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7065
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
137 words
A mask pattern printing device for a mask having a prescribed pattern, a photo-sensitive plate on which the pattern of the mask is photographed and printed, optical means for passing an illuminating beam of light along a path through the mask and onto the plate and a reflected beam from the plate, and a mask pattern observation means, being characterized by a means to polarize the illuminating light through the Mask at the time of observation, said observation means including means in the optical path between the mask and the photo-sensitive plate to virtually delay the polarization state of the polarized luminous beam by a quarter wavelength, and said observation means including analyzer means in the reflected path, for eliminating the harmful reflected light from the mask and observing the reflected light from the photo-sensitive plate only.
Claim 2
Dependent Claim
137 words
A mask pattern printing device for a mask having a prescribed pattern, a photo-sensitive plate on which the pattern of the mask is photographed and printed, optical means for passing an illuminating beam of light along a path through the mask and onto the plate and a reflected beam from the plate, and a mask pattern observation means, being characterized by a means to polarize the illuminating light through the Mask at the time of observation, said observation means including means in the optical path between the mask and the photo-sensitive plate to virtually delay the polarization state of the polarized luminous beam by a quarter wavelength, and said observation means including analyzer means in the reflected path, for eliminating the harmful reflected light from the mask and observing the reflected light from the photo-sensitive plate only.
Claim 3
Dependent Claim
25 words
The mask pattern printing device in claim 1, in which said analyzer means include rotatable means for making the contrast of the mask pattern variable.
Claim 4
Dependent Claim
120 words
The mask pattern printing device in claim 1 in which the optical means includes an imaging lens having an exit pupil at or almost at infinity and the reflective photo-sensitive plate is positioned conjugate with the mask at the exit end of the imaging lens and an illumination optical system in the path before the mask, said observation means including a beam splitter and an alignment optical system between said mask and the illumination optical system and an optical means for condensing characteristics between said beam splitter and said illumination optical system so that the numerical aperture of the illumination optical system at the time of observation is increased to a greater value than that at the time of printing.
Claim 5
Dependent Claim
79 words
The mask pattern printing device in claim 1, in which said observation means includes an alignment optical system and a beam splitter to pass the light passing toward the mask and deflect the light reflected back through the mask to the alignment optical system and said polarizing means form part of said observation means and a means to rotate said analyzer means within a plane perpendicular to the reflected beam, thus making the contrast of the mask pattern variable.
Claim 6
Dependent Claim
39 words
The mask pattern printing device in claim 1, in which said observation means includes an alignment optical system and a beam splitter to split the light beam to the alignment optical system between said mask and the illuminating means.
Claim 7
Dependent Claim
65 words
The mask pattern printing device in claim 1, in which said illuminating means includes a light source and a tubular shaped member having reflective inner walls and an incident end plane coinciding with the light source and an exit end plane, said exit end plane forming a secondary light source so that unevenness of the intensity of illumination of the first light source is eliminated.
Claim 8
Dependent Claim
82 words
The mask pattern printing device in claim 1, in which said observation means includes a beam splitter in the path of the reflected light for deflecting light and an alignment optical system in the path of the deflected light, an observation filter between said optical means and the mask, said optical means including an optical system having a shifting objective lens between the above mentioned beam splitter and the illuminating optical means, thus always concentrating the luminous flux to an observation point.
Claim 9
Dependent Claim
129 words
A mask pattern printing device for printing the pattern of a mask on a photosensitive surface, including optical means for furnishing an illuminating beam and directing the illuminating beam through the mask onto the surface so as to form a reflected beam, polarizing means for polarizing light, delay means for delaying polarized light one-quarter wavelength, analyzer means for analyzing incident light, and observation means for locating said polarizing means in the illuminating beam before the illuminating beam reaches the mask to polarize the illuminating beam passing through the mask and placing said delay means in the illuminating beam between the mask and the photosensitive surface and for causing said analyzer means to protrude into the reflected beam between the polarizing means and the mask to analyze the reflected light.
Claim 10
Dependent Claim
129 words
A mask pattern printing device for printing the pattern of a mask on a photosensitive surface, including optical means for furnishing an illuminating beam and directing the illuminating beam through the mask onto the surface so as to form a reflected beam, polarizing means for polarizing light, delay means for delaying polarized light one-quarter wavelength, analyzer means for analyzing incident light, and observation means for locating said polarizing means in the illuminating beam before the illuminating beam reaches the mask to polarize the illuminating beam passing through the mask and placing said delay means in the illuminating beam between the mask and the photosensitive surface and for causing said analyzer means to protrude into the reflected beam between the polarizing means and the mask to analyze the reflected light.
Claim 11
Dependent Claim
47 words
A device as in claim 8, wherein said observation means movably couples said polarizer means and said analyzer means relative to said optical means so as to allow movement of said polarizing means and said analyzer mEans into and out of the path of the illuminating beam.
Claim 12
Dependent Claim
27 words
A device as in claim 8, wherein said analyzer means includes a half mirror for deflecting the reflected beam transversely and allowing passage of said illuminating beam.
Claim 13
Dependent Claim
27 words
A device as in claim 9, wherein said analyzer means includes a half mirror for deflecting the reflected beam transversely and allowing passage of said illuminating beam.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |