EP0242066A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Wafer positioning system
Assignee: Varian Medical Systems Inc
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Filing: 1987-03-23
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Granted: —
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Expires: 2007-03-23
Abstract
Abstract In order to compensate for worn or distorted wafer cassettes and missing wafers, the cassette of wafers is scanned through a beam. The timing of the interruptions of the beam is used to inventory the wafers present and measure the exact position of each wafer relative to the base of the cassette.
Inventors
- 👤 Frederick P. Layman
- 👤 Michael J. Kuhlman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 20:03
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/50; H10P72/53; H10P72/30; H10P72/32; H10P72/3218; Y; Y10; Y10S; Y10S414/00; Y10S414/135; Y10S414/137; Y10S414/139
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
77 words
A system for handling a cassette of workpieces comprising: transmitter means for sending a closely collimated beam of radiation; receiver means for detecting the closely collimated beam of radiation; transport means for moving the cassette past the collimated beam of radiation at a constant speed; signal processing means for translating interruptions in the collimated beam of radiation as a function of time into position information; computer means for receiving and storing information from said signal processing means.
Claim 2
Independent Claim
77 words
A system for handling a cassette of workpieces comprising: transmitter means for sending a closely collimated beam of radiation; receiver means for detecting the closely collimated beam of radiation; transport means for moving the cassette past the collimated beam of radiation at a constant speed; signal processing means for translating interruptions in the collimated beam of radiation as a function of time into position information; computer means for receiving and storing information from said signal processing means.
Claim 3
Dependent Claim
26 words
A system as in claim 1 wherein said transport means is an elevator which raises and lowers the cassette with the wafers in a horizontal plane.
Claim 4
Dependent Claim
19 words
A system as in claim 2 wherein said transmitter and said detector are matched to operate with infrared radiation.
Claim 5
Dependent Claim
19 words
A system as in claim 2 wherein said transmitter and said detector are matched to operate with visible radiation.
References Cited (Backward Citations)
No citation records indexed.
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