← Back to Patent Explorer
US4794263A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for measuring crystal diameter

Assignee: SEH America Inc
•
Filing: 1987-10-19
•
Granted: 1988-12-27
•
Expires: 2007-10-19
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus for measuring the diameter of a crystal in which an optical sensor scans along a sensing line which crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; the picture element position corresponding to a maximum luminance is discriminated when the optical sensor scans; the mean value of the picture element position is calculated over at least one revolution of the crystalline rod; and the diameter D of the crystalline rod at a portion thereof interfacing with the melt is calculated from the mean value and the level of the melt. Similarly, the minimum crystal diameter can be calculated by obtaining the picture element position corresponding to the minimum crystal diameter instead of obtaining the mean of the picture element position.

Inventors

  • 👤 Nobuo Katsuoka
  • 👤 Yoshihiro Hirano
  • 👤 Atsushi Ozaki
  • 👤 Masahiko Baba

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 20:53
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/08; Y; Y10; Y10T; Y10T117/00; Y10T117/10; Y10T117/1004; Y10T117/1012

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 139 words
An apparatus for measuring the diameter of a crystal comprising: an optical sensor whose sensing line crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; peak luminance position discriminating means for determining a picture element position P corresponding to a maximum luminance, by making said optical sensor scan; mean peak luminance position calculating means for calculating a mean value P of said picture element position P over at least one revolution of said crystalline rod; level detecting means for detecting the level H of said melt; and crystal diameter calculating means for calculating from said mean value P and said level H the diameter D of said crystalline rod at the portion thereof interfacing with said melt, said crystal diameter calculating means outputting a signal corresponding to said diameter D.
Claim 2
Independent Claim 139 words
An apparatus for measuring the diameter of a crystal comprising: an optical sensor whose sensing line crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; peak luminance position discriminating means for determining a picture element position P corresponding to a maximum luminance, by making said optical sensor scan; mean peak luminance position calculating means for calculating a mean value P of said picture element position P over at least one revolution of said crystalline rod; level detecting means for detecting the level H of said melt; and crystal diameter calculating means for calculating from said mean value P and said level H the diameter D of said crystalline rod at the portion thereof interfacing with said melt, said crystal diameter calculating means outputting a signal corresponding to said diameter D.
Claim 3
Dependent Claim 34 words
An apparatus according to claim 1, wherein the optical axis of said optical sensor is in a plane which contains the center axis of said crystalline rod or in the vicinity of said plane.
Claim 4
Dependent Claim 15 words
An apparatus according to claim 2, wherein said optical sensor is an one-dimensional image sensor.
Claim 5
Dependent Claim 23 words
An apparatus according to claim 2, wherein said optical sensor is a two-dimensional image sensor which makes use of a specific scanning line.
Claim 6
Dependent Claim 30 words
An apparatus according to claim 3, wherein said mean peak position calculating means calculates a mean value P of said picture element position P over an integral number of revolutions.
Claim 7
Dependent Claim 70 words
An apparatus according to claim 3, wherein said level detecting means has: means for detecting the initial position of the surface of said melt; means for detecting the distance through which a crucible which contains said melt is lifted; means for detecting the weight of a raise part of said crystalline rod; and means for calculating the level of said melt from said initial position, said distance and said weight.
Claim 8
Independent Claim 155 words
An apparatus for measuring the diameter of a crystal comprising: an optical sensor whose sensing line crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; peak luminance position discriminating means for determining a picture element position P corresponding to a maximum luminance by making said optical sensor scan; minimum diameter peak position discriminating means for obtaining a picture element position Pm corresponding to a minimum crystal diameter Dm by using data on said picture element position P over at least one revolution of said crystalline rod; level detecting means for detecting the level H of said melt; and crystal diameter calculating means for calculating from said picture element position Pm and said level H said minimum crystal diameter Dm of said crystalline rod at a portion thereof interfacing with said melt, said crystal diameter calculating means outputting a signal corresponding to said minimum crystal diameter Dm.
Claim 9
Independent Claim 155 words
An apparatus for measuring the diameter of a crystal comprising: an optical sensor whose sensing line crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; peak luminance position discriminating means for determining a picture element position P corresponding to a maximum luminance by making said optical sensor scan; minimum diameter peak position discriminating means for obtaining a picture element position Pm corresponding to a minimum crystal diameter Dm by using data on said picture element position P over at least one revolution of said crystalline rod; level detecting means for detecting the level H of said melt; and crystal diameter calculating means for calculating from said picture element position Pm and said level H said minimum crystal diameter Dm of said crystalline rod at a portion thereof interfacing with said melt, said crystal diameter calculating means outputting a signal corresponding to said minimum crystal diameter Dm.
Claim 10
Dependent Claim 34 words
An apparatus according to claim 7, wherein the optical axis of said optical sensor is in a plane which contains the center axis of said crystalline rod or in the vicinity of said plane.
Claim 11
Independent Claim 15 words
An apparatus according to laim 8, wherein said optical sensor is an one-dimensional image sensor.
Claim 12
Independent Claim 15 words
An apparatus according to laim 8, wherein said optical sensor is an one-dimensional image sensor.
Claim 13
Dependent Claim 23 words
An apparatus according to claim 8, wherein said optical sensor is a two-dimensional image snnsor which makes use of a specific scanning line.
Claim 14
Dependent Claim 42 words
An apparatus according to claim 9, wherein said minimum diameter peak position calculating means calculates said picture element position Pm corresponding to said minimum crystal diameter Dm by using data on said picture element position P over an integral number of revolutions.
Claim 15
Dependent Claim 70 words
An apparatus according to claim 9, wherein said level detecting means has: means for detecting the initial position of the surface of said melt; means for detecting the distance through which a crucible which contains said melt is lifted; means for detecting the weight of a raised part of said crystalline rod; and means for calculating the level of said melt from said initial position, said distance and said weight.

References Cited (Backward Citations)

US4207293A Cited
US3958129A Cited
US4617173A Cited
US4710258A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-12-27 1992-06-27 1992-12-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-12-27 1996-06-27 1996-12-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-12-27 2000-06-27 2000-12-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag