IRRADIATION APPARATUS, APPARATUS AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF DISPLAY DEVICE

PROBLEM TO BE SOLVED: To irradiate an object to be irradiated with laser light without being affected by an individual difference of a semiconductor laser or the like by attaining optimization of a focal position with respect to a required beam diameter. SOLUTION: In an irradiation apparatus which irradiates an object to be irradiated with emitted beam light from a semiconductor laser, when a radius of a radiation beam to the object to be irradiated is defined as (w), a ratio of a diffusion angle spreading individual difference of the semiconductor laser is defined as Δ and a beam wavelength of the semiconductor laser is defined as λ, a focal position of a radiation optical system interposed between the semiconductor laser and the object to be irradiated is defocused in such a way that a distance (z) between the focal position and the object to be irradiated becomes a value derived from (w) and Δ by a predetermined operational expression. COPYRIGHT: (C)2009,JPO&INPIT