Modulated light (image light) which has been modulated by passing through a liquid crystal display panel passes through an apical angle variable prism (so-called, a vari-angle prism) and then is enlarged and projected by a projection lens. The apical angle variable prism is configured to change the prism apical angle with, for example, an electromagnetic actuator. The microcomputer calculates a projection optical axis correction value based on hand shake detection signals from a sensor and controls the aforementioned actuator based on the correction value. With this control, shakes of projected images due to hand shakes are prevented.