Patent ID: 7929127
Filing Date: 2011-04-19
Classification: B23K,G01J

Abstract:
1. A laser energy measuring unit comprising: a mask having a plurality of mask holes with different diameters, said mask being configured so that one of said mask holes is selectively positioned within an optical path of a laser beam; an attenuating member within the optical path of the laser beam downstream of said mask so as to attenuate energy of the laser beam having passed through said mask, said attenuating member having: a measuring device for measuring the energy of the laser beam having passed through said attenuating member such that a center part of an energy of the laser beam has been blocked by said circular shading portion of said attenuating member to thereby minimize the energy of the laser beam; and a condenser lens located at one side of said attenuating member, said condenser lens being configured to condense the laser beam having passed through said mask to said measuring device.