A light amount is increased and an analyzing accuracy can be kept in accordance with an enlargement of a load angle, however, a scattered light tends to be loaded in an analysis accompanying the scattered light and a dynamic range of a concentration which can be measured becomes narrow. A light is dispersed by a light dispersing portion, a load angle of the received light is changed per wavelength, the load angle is made larger in the light of a wavelength having a small light amount, and the load angle is made smaller in the light a wavelength having a large light amount and used for an analysis accompanying a scattered light. Accordingly, it is possible to gain a dynamic range of a concentration which can be measured in the analysis accompanying the scattered light, while increasing the light amount and maintaining the analyzing accuracy.