The invention includes an irradiation nozzle which radiates a line scanning beam, an irradiation position sensor which detects an irradiation position of the line scanning beam, an arithmetic processing circuit unit which measures the stationary time of the line scanning beam at the irradiation position detected by the irradiation position sensor, and an irradiation control unit which performs scanning control of the line scanning beam by utilizing the irradiation position measured by the irradiation position sensor and the stationary time detected by the arithmetic processing circuit unit. According to this line scanning apparatus, scanning control of the line scanning beam is performed by utilizing the irradiation position of the beam and the stationary time corresponding to the irradiation position, so that irradiation of the beam to an erroneous position or excessive irradiation of the line scanning beam can be more reliably prevented, and thereby the reliability of the line scanning apparatus can be improved.
