A projection-type image display apparatus that enlarges and displays an image includes: a case, a laser light source, a cooling mechanism that includes a component that produces vibration during operation, a diffuser that diffuses light that is emitted from the laser light source, optics that shape light diffused by the diffuser to light having a uniform luminance distribution and rectangular cross-section, and an optical modulation element that modulates light shaped by the optics; wherein the component included in the cooling mechanism and the diffuser are connected by way of a vibration transmitting member.