Illumination device and projector using it

摘要

An illumination device comprises:an integrator (20) that transmits light from an incident side (20a) thereof to an emitting side (20b) thereof; a light source (12) that supplies the light to the incident side (20a) of the integrator (20), the light source (12) including a reflector (14) and a lamp (13) located on a center axis (14c) of the reflector (14); and a center mirror (30) located on a line connecting the center of the incident side (20a) of the integrator (20, 21) and the lamp (13), the center mirror (30) being capable of reflecting light from the integrator (20, 21) back to the integrator (20, 21). The center mirror (30) has a diameter smaller than that of an opening (14a) of the reflector (14).