A continuous lighting lamp irradiates a semiconductor wafer held by a quartz susceptor with light from below to perform preliminary heating, and then irradiation of a flash of light is performed by a flash lamp from above. A light absorption ring is provided so as to be close to a peripheral portion of the semiconductor wafer held by the susceptor. The light absorption ring absorbs infrared light and transmits visible light through itself. During preliminary heating, the light absorption ring absorbs light emitted from the continuous lighting lamp to be increased in temperature so that heat radiated from the peripheral portion of the wafer is compensated to cause in-plane temperature distribution of the semiconductor wafer to be uniform. Meanwhile, the flash of light is transmitted through the light absorption ring, so that the light absorption ring is prevented from being damaged by the irradiation of the flash of light.