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:
Oct. 16, 2012
Filed:
Jun. 02, 2005
Yoshiaki Kojima, Saitama, JP;
Yoshiaki Kojima, Saitama, JP;
NuFlare Technology, Inc., Numazu-shi, JP;
Abstract
It is an object of the present invention to make it possible to stably and correctly measure a changing amount of a beam position when a beam displacement is measured prior to a recording operation performed by an electron beam recording apparatus. A measuring device for measuring a displacement of an electron beam prior to a recording operation, comprises: a knife edge disposed at an irradiating position of the beam spot; detecting means (Farady cup or the like) for detecting an electron beam irradiating through the knife edge; filter means (high frequency cut filter or the like) for removing a changing frequency component of measurement subject from an output of the detecting means; and control means for controlling a reference position of the electron beam in accordance with an output from the filter means, in a manner such that the center of the beam spot will be at the front end position of the knife edge. A displacement of the beam spot is measured in accordance with an output change of the detecting means when the center of the beam spot deviates from the front end of the knife edge.