Patent ID: 7844188

Claim:
A light collecting device, comprising: an excitation light source that emits excitation light to one end of an optical fiber; a light condensing optical system that condenses the excitation light emitted from an input-output part at another end of the optical fiber to a light emission structure, and directs reflected light reflected in the light emission structure and emission light generated by the excitation light in the light emission structure to the input-output part, a wavelength of said emission light being different from a wavelength of the excitation light; a reflecting light detector that detects intensity of the reflected light; a first optical divider that divides the emission light and the reflected light propagating in the optical fiber based on a light wavelength, directs the emission light to the input-output part, and propagates the reflected light to the excitation light source; a second optical divider that is arranged at a position of the optical fiber closer to the excitation light source than to the first optical divider, propagates the excitation light to the first optical divider, and propagates the reflected light to the reflecting light detector; a position controller that controls a light condensing position of the excitation light to be irradiated to the light emission structure; a shape information acquisition unit that scans the light condensing position of the excitation light, and acquires a relationship between the intensity of the reflected light and the light condensing position of the excitation light; and a light condensing position optimizing unit that optimizes the light condensing position based on the intensity of the reflected light and the light condensing position of the excitation light.