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:
Nov. 06, 2012
Filed:
Jun. 15, 2009
Ken Minoda, Utsunomiya, JP;
Ken Minoda, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A projection exposure apparatus includes an aperture stop that includes a light attenuation part that is located between a light shielding part and an opening part, and has a transmittance larger than that of the light shielding part and smaller than that of the opening part. A width of the light attenuation part is set within a range from a wavefront splitting period of the wavefront splitting device or a value of Z×tan(arcsin(α))/2 to a length that is five times as long as the wavefront splitting period of the wavefront splitting device, where α is a numerical aperture on an exit side of the wavefront splitting device, and Z is a distance between the focal plane of the wavefront splitting device on the exit side and the aperture stop.