An object of the present invention is to provide a small-sized polymerization apparatus which can be easily carried and carried, which can increase the intensity of light applied to an object to be polymerized, and which can perform stable and highly accurate polymerization curing. Kind Code: A1 Abstract: In a polymerization apparatus having a light irradiator having a light source chamber in which an LED package with a heat sink is disposed and a polymerization container for performing photopolymerization of an object, groove-shaped ventilation between heat radiation fins of a heat sink. An intake fan 250 and an exhaust fan 260 are disposed at both ends of the road, respectively, and by driving both fans in synchronization, the cooling efficiency is improved in a small space, and at the same time, the cooling air is blown so as not to hit the peripheral device with hot air. Regulate flow. [Selection] Figure 2
