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:
Jun. 23, 1992
Filed:
May. 24, 1990
Olivier Hignette, St Germain les Corbeil, FR;
Micro-Controle, , FR;
Abstract
The width of a line projecting out of or recessed on a medium such as an integrated circuit is measured. A device for that purpose includes a confocal optical assembly having a monomode light source delivering a beam having a flat wave front. An optical deflector scans the surface of the medium transversely to the line width of the beam. A separator separates the light beam directed towards the medium carrying the line from the beam reflected by the medium. A detector includes a blade placed at a position conjugate with the focal point of the optical assembly and orthogonal to the line whose width is to be measured and a differential sensor placed at a position conjugate with the pupil of the optical assembly and delivering a signal responsive to the difference of lighting on each side of the blade for comparison with a threshold.