LIGHT IRRADIATION APPARATUS

An object is to provide a light irradiation apparatus irradiating a light to a sample in a reaction vessel while stirring the sample more efficiently. A rotating stage can rotate around a first axis being a central axis thereof. A holding mechanism holds reaction vessels whose longitudinal directions are a direction of the central axis on a circumference around the first axis on the rotating stage at equal intervals. Rotation mechanisms hold bottoms of the reaction vessels and rotate the reaction vessels around second axes being central axes of the reaction vessels, respectively. Light irradiation mechanisms are arranged on a circumference outside of the rotating stage and at least one light emitting diode is disposed in each light irradiation mechanism. Stirring mechanisms are arranged in the vicinity of the reaction vessels and rotate stir bars around axes of directions orthogonal to the second axes by magnetic force, respectively.