Patent US4671981A successfully refreshed from Google Patents.
US3872575A
Expired / Lapsed
US
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Optical transducer scale
Assignee: Control Data Corp
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Filing: 1974-03-25
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Granted: 1975-03-25
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Expires: 1994-03-25
Abstract
Abstract An optical grating which has a preselected coefficient of thermal expansion can be made by attaching grating bars to a slotted plate having the desired coefficient of thermal expansion in a position making the bars visible through the slot. The grating bars are transverse to the slot and firmly bonded to its edges, and are carried by a transparent sheet whose effect on thermal expansion of the plate is negligible.
Inventors
- 👤 Charles Benjamin Lee
- 👤 Franz Ucko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:57
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/008; G01; G01B; G01B3/00; G01B3/002; G01B3/004; G02B5/00; G02B5/18; Y; Y10; Y10S; Y10S359/00; Y10S359/90; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1056; Y10T156/1062; Y10T156/1064; Y10T156/1074
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
135 words
A method for forming an optical grating having the thermal expansion characteristics of a preselected material, comprising the steps of a. forming a flat plate of material having the thermal expansion characteristics of the preselected material; b. cutting a slot of preselected width piercing the plate; c. forming a thin flat sheet wider in a first direction than the slot, whose elongation per unit length per unit tension perpendicular to the first direction is substantially greater than for the plate along the direction of its slot, said sheet having a transparent layer; d. forming on the sheet a plurality of slits generally lying in the first direction which form the desired grating pattern, and e. bonding the sheet to the plate in a position situating at least a portion of each slit within the slot.
Claim 2
Independent Claim
135 words
A method for forming an optical grating having the thermal expansion characteristics of a preselected material, comprising the steps of a. forming a flat plate of material having the thermal expansion characteristics of the preselected material; b. cutting a slot of preselected width piercing the plate; c. forming a thin flat sheet wider in a first direction than the slot, whose elongation per unit length per unit tension perpendicular to the first direction is substantially greater than for the plate along the direction of its slot, said sheet having a transparent layer; d. forming on the sheet a plurality of slits generally lying in the first direction which form the desired grating pattern, and e. bonding the sheet to the plate in a position situating at least a portion of each slit within the slot.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein the bonding step includes the step of simultaneously applying tension to the sheet during the bonding step.
Claim 4
Dependent Claim
13 words
The method of claim 1, wherein the slit-forming step follows the sheet-bonding step.
Claim 5
Dependent Claim
13 words
The method of claim 1, wherein the slit-forming step precedes the sheet-bonding step.
Claim 6
Dependent Claim
30 words
The method of claim 1, wherein the thin flat sheet-forming step further includes the step of dimensioning the sheet to completely overlap the slot in the plate on all sides.
Claim 7
Dependent Claim
20 words
The method of claim 1, wherein the plate-forming step includes the step of forming the plate from the preselected material.
Claim 8
Dependent Claim
36 words
The method of claim 1, wherein the sheet-forming step comprises forming a sheet having an opaque layer and a transparent layer and the slit-forming step comprises removing portions of the opaque layer to form the slits.
Claim 9
Dependent Claim
24 words
The method of claim 1, wherein the slit-forming step comprises the step of depositing opaque bars on the sheet defining the slits between them.
References Cited (Backward Citations)
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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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |