US3749052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tilting variable speed rotary shadower
Assignee: LADD RES IND
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Filing: 1971-11-15
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Granted: 1973-07-31
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Expires: 1991-11-15
Abstract
Abstract Method and apparatus for completely and uniformly coating a specimen for examination by a scanning electron microscope. The specimen is rotated and precessed for exposure of all upper portions to the beam of coating vapor, and is variably shielded from the beam to ensure uniformly thick coating of all portions.
Inventors
- 👤 J Porter
- 👤 W Ladd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:31
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/50; C23C14/505
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
203 words
Apparatus for rotating and precessing a specimen for uniform exposure to an incident beam whose direction of incidence defines a beam axis comprising a rotatable support table adapted to hold the specimen at a location spaced from the axis of the table, and mechanism for moving said table bodily about a second axis inclined to the axis of said table while simultaneously rotating the table about its own axis, for precessional movement of said rotating table between a first position in which said beam is incident normally upon the surface of said table for exposure of the top of said specimen to said beam, and a second position in which said beam is parallel to said table surface for exposure of side portions of said specimen to said beam, and shielding means for shielding from said beam a specimen held on said table during a part of each revolution of said specimen about said axis of said table, said part increasing from nothing in said second position to approximately 3/4 of a revolution in said first position, whereby the total exposure of the specimen to said beam during said precessional motion is uniform for all areas of the upper portion of said specimen.
Claim 2
Dependent Claim
203 words
Apparatus for rotating and precessing a specimen for uniform exposure to an incident beam whose direction of incidence defines a beam axis comprising a rotatable support table adapted to hold the specimen at a location spaced from the axis of the table, and mechanism for moving said table bodily about a second axis inclined to the axis of said table while simultaneously rotating the table about its own axis, for precessional movement of said rotating table between a first position in which said beam is incident normally upon the surface of said table for exposure of the top of said specimen to said beam, and a second position in which said beam is parallel to said table surface for exposure of side portions of said specimen to said beam, and shielding means for shielding from said beam a specimen held on said table during a part of each revolution of said specimen about said axis of said table, said part increasing from nothing in said second position to approximately 3/4 of a revolution in said first position, whereby the total exposure of the specimen to said beam during said precessional motion is uniform for all areas of the upper portion of said specimen.
Claim 3
Dependent Claim
147 words
The apparatus of claim 1 wherein said specimen support table provides peripheral support means, and said mechanism includes a first shaft supporting said table, a rotatable second shaft inclined to said first shaft and rotatably supporting it, power means to rotate said second shaft, a drive track concentric with said second shaft, said first shaft having cooperative drive means engaging said drive track, said drive means comprising an annulus of elastomeric material surrounding a conical portion of said first shaft for adjustable frictional engagement of said drive track, providing a variable ratio of angular speed about said first shaft to angular speed about said second shaft, whereby, when said second shaft is rotated, said drive means engages said drive track for rotation of said first shaft about an axis that rotates about said second shaft for precessional motion of said first shaft and said specimen support table.
Claim 4
Dependent Claim
28 words
The apparatus of claim 2 wherein said specimen support table rotates about said first shaft more than once while said first shaft rotates once about said second shaft.
Claim 5
Dependent Claim
35 words
The apparatus of claim 1 wherein said shielding means comprises first and second shields, said first shield being rotatable about said second axis, and said second shield being fixed with respect to said second axis.
Claim 6
Dependent Claim
62 words
The apparatus of claim 1 wherein said first shield is generally planar, extends coplanar with said specimen support table and spaced therefrom, covering less than one-half of the area of said support table but more than one-quarter of said area, and said second shield is generally planar and extends parallel to said second axis to a point just below said beam axis.
Claim 7
Dependent Claim
44 words
The apparatus of claim 5 wherein said first shield extends over approximately 7/16 of said support table area, and the portion of said second shield proximate to said beam terminates in a point bounded by two straight edges including an angle of about 83*.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |