Provided is a method for calculating a scanning pattern of light and an optical scanning apparatus which are capable of obtaining a high-quality image without imposing constraints on the hardware. The method according to a first aspect includes the steps of: detecting a resonance frequency and an attenuation coefficient of an oscillation part of an optical fiber which guides light from a light source and irradiates an object with the light and calculating a scanning pattern of the light, based on the detected resonance frequency and attenuation coefficient. The method according to a second aspect includes the steps of: detecting, using position data detected by a scanning position detector, a scanning pattern of light from an oscillation part of an optical fiber which guides the light from a light source and irradiates an object with the light and calculating an approximation coefficient of temporal change in phase shift of the oscillation part included in the scanning pattern. The apparatus according to a first aspect includes: an optical fiber which guides light from a light source and irradiates an object with the light a scanning part which drives an oscillation part oscillatably supported of the optical fiber a detector which detects a resonance frequency of the oscillation part a calculation part which determines an irradiation position of the light using a scanning pattern calculated based on the resonance frequency detected by the detector and the attenuation coefficient obtained in advance. The apparatus according to a second aspect includes: an optical fiber which guides light from a light source and irradiates an object with the light a scanning part which drives an oscillation part oscillatably supported of the optical fiber and a calculation part which calculates, using position data detected by a scanning position detector, an approximation coefficient of temporal change in phase shift of the oscillation part included in the scanning pattern.
