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. 12, 2001
Filed:
Dec. 21, 1998
Peter C. Tiemeijer, Eindhoven, NL;
Philips Electron Optics B.V., Eindhoven, NL;
Abstract
particle-optical apparatus at a comparatively low acceleration voltage (from 0.5 kV to 5 kV). This lens defect cannot be eliminated by means of rotationally-symmetrical fields. In order to enhance the resolution nevertheless, it has already been proposed to mitigate said lens defect by means of a corrector of the Wien type. This known configuration consists of a number of electrical and magnetic multipoles. In order to adapt the corrective capacity of the corrector,to the strength of the objective,to be corrected and to achieve less severe requirements in respect of mechanical tolerances, according to the invention the corrector,is excited in such a manner that the trajectory of the electrons constitutes a sinusoid of a length which does not deviate more than 10% from a full sine period, upstream and downstream from the correction device there being arranged an n-pole, where n=4, 6, . . . (,), at a distance which is less than,of the length of the corrector.