The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 23, 1989
Filed:
Oct. 29, 1986
Applicant:
Inventor:
Friedrich W Thomas, Gelnhausen, DE;
Assignee:
Leybold-Heraeus GmbH, Cologne, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356384 ; 356 72 ; 356375 ;
Abstract
A method and apparatus for measuring the diameter of a monocrystal during crucible drawing determines the brightness profile at the melt/monocrystal change-over point. The spacial position of maxima in the brightness profile in relation to a reference point indicates the diameter. The brightness profile is obtained by optically scanning the melt/monocrystal change-over point with a mirror rotating about a horizontal axis, applying the optical beam reflected by the rotating mirror to a row of photosensitive elements in parallel with the axis, and analyzing the outputs corresponding to the brightness profile for determining the diameter.