Patent US3892491A successfully refreshed from Google Patents.
US3892491A
Expired / Lapsed
US
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Comparator, optical inspection
Assignee: United States Department of the Army
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Filing: 1974-07-02
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Granted: 1975-07-01
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Expires: 1994-07-02
Abstract
Abstract Two identical thin lenses are placed side by side and in the same plane level above work being examined which is located at approximately the lenses focal length. Observer''s eye is at a controlled center between the lenses and at a distance about double their focal length. Observer sees alternately two magnified images of the work with one eye, so as to compare a standard with a sample.
Inventors
- 👤 Albert E Kanode
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:03
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G01N21/95607; G01B; G01B11/00; G01B11/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
268 words
A method of comparing a first object with a second object with the use of first and second lenses comprising the steps of aligning said first and second objects in predetermined spacial relationship to each other in a first plane; choosing first and second lenses which are identical in their optical and physical characteristics; aligning said first and second lenses in a second plane which is parallel to the first plane such that from a fixed point an image is formed due to the first lens which is a first portion of the first object and a second image is formed due to the second lens which is a portion of the second object which corresponds to said portion of said first object; placing said fixed point on a centerline between the two lenses and at a distance of double their focal lengths; locating said first and second planes at a distance equal to the focal length of the lenses; observing the two images alternately with a single observation means located at said fixed point; moving the plane of the first and second lenses relative to said first and second objects so as to provide for more precise focusing of the images to be viewed; moving the second lens in the second plane so as to provide precise alignment of the image of the portions of the second object with respect to the image of the portions of said first object viewed through said first lens; and moving said first and second objects simultaneously so that all corresponding portions of said first and second objects can be compared.
Claim 2
Independent Claim
268 words
A method of comparing a first object with a second object with the use of first and second lenses comprising the steps of aligning said first and second objects in predetermined spacial relationship to each other in a first plane; choosing first and second lenses which are identical in their optical and physical characteristics; aligning said first and second lenses in a second plane which is parallel to the first plane such that from a fixed point an image is formed due to the first lens which is a first portion of the first object and a second image is formed due to the second lens which is a portion of the second object which corresponds to said portion of said first object; placing said fixed point on a centerline between the two lenses and at a distance of double their focal lengths; locating said first and second planes at a distance equal to the focal length of the lenses; observing the two images alternately with a single observation means located at said fixed point; moving the plane of the first and second lenses relative to said first and second objects so as to provide for more precise focusing of the images to be viewed; moving the second lens in the second plane so as to provide precise alignment of the image of the portions of the second object with respect to the image of the portions of said first object viewed through said first lens; and moving said first and second objects simultaneously so that all corresponding portions of said first and second objects can be compared.
References Cited (Backward Citations)
US2040066A
Cited
US3753617A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |