A liquid crystal projector apparatus has a liquid crystal unit having a liquid crystal panel for modulating light, an incident side polarizing plate and an exit side polarizing plate disposed in front of and behind the liquid crystal panel along the optical axis, respectively, a first holder member for holding the liquid crystal unit, a first heat exchanger disposed in close proximity to the first holder member for dissipating heat generated by the liquid crystal unit and then conducted to the first holder member using a coolant liquid which passes through a first channel formed inside the first heat exchanger, a pump for circulating the coolant liquid, and a radiator for cooling the coolant liquid.