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. 10, 1988
Filed:
Jun. 13, 1986
Applicant:
Inventor:
Roland Thoms, Mullheim, DE;
Assignee:
BMC Industries, Inc., St. Paul, MN (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
313402 ; 313403 ;
Abstract
An aperture mask having a grade side and a cone side with a plurality of openings of substantially the same size with the plurality of openings having a grade side partially etched region and a cone side partially etched region surrounding the plurality of openings, the grade side partially etched region surrounding the plurality of openings decreasing from the center of the mask to the periphery of the mask.