Patent ID: 7109435
Filing Date: 2006-09-19
Classification: B23K,C21D

Abstract:
1. A light irradiator comprising: a laser source which emits a laser beam; a beam splitting means for splitting a laser beam emitted from the laser source into a plurality of laser beams; and an irradiating means for receiving the plurality of laser beams incident thereupon and irradiating the incident laser beams to an object to be irradiated with the laser beams; the beam splitting means including: k (k is a natural number larger than 1) beam splitters each having a beam splitting surface which splits an incident laser beam into two laser beams, namely, reflected and transmitted parts, by reflecting and transmitting, the beam splitting surfaces being disposed in parallel to each other; and a reflecting mirror having a light reflecting surface parallel to the beam splitting surface of each beam splitter and upon which the reflected parts from all the beam splitters is incident; the laser beam emitted from the laser source being incident upon the first one, counted from the laser source, of the beam splitters; the laser beam transmitted through the m-th beam splitter and the laser beam reflected by the m-th beam splitter and then by the reflecting mirror being incident upon the (m+1)th (m is a natural number) beam splitter; the k-th beam splitter providing 2 the reflecting mirror reflecting 2 the distance between the beam splitting surface of the first beam splitter and that of the (m+1)th beam splitter, and the distance between the beam splitting surface of the first beam splitter and the reflecting surface of the reflecting mirror, being adjusted for an optical path difference between 2 the distance between the beam splitting surface of the m-th beam splitter and that of the (m+1)th beam splitter is larger than (2