Patent ID: 7361221
Filing Date: 2008-04-22
Classification: B23K,G03F,H01L,Y10T

Abstract:
1. A light irradiation apparatus comprising: a light modulation element which has at least one unit phase modulation area having at least one basic pattern for modulating a light beam; an illumination system which illuminates the unit phase modulation area of the light modulation element with a light beam; and an image formation optical system which causes a light beam having on an irradiation target surface a light intensity distribution having an inverse-peak-shaped pattern formed based on the light beam phase-modulated by the phase modulation element to fall on an irradiation target object, wherein dimensions of the basic pattern of the unit phase modulation area are not greater than a point spread function range of the image formation optical system converted in terms of the light modulation element, and the unit phase modulation area is configured in such a manner that a phase distribution in a light complex amplitude distribution on the irradiation target surface becomes a saw-tooth-like distribution along a line segment in a lateral direction.