Bend information computation apparatus includes: an input unit having detected light quantity information representing a relation between a wavelength in a predetermined wavelength band and a light quantity, the detected light quantity information being acquired using a light guide having at least one light absorber for changing a light quantity of light transmitted through the light guide according to a bent state of the light absorber to detect a light quantity after a change； and an arithmetic operator for computing bend information representing a bend direction and a bend magnitude of each light absorber based on the detected light quantity information, an absorption spectrum of each light absorber, a bend coefficient of each light absorber that varies according to a bend direction and a bend magnitude of each light absorber, and a unique characteristic value of each light absorber including a value for a correction relating to the bend coefficient.
