Lamp unit and image projection apparatus

摘要

A lamp unit includes a lamp provided with a mirror and a house for holding the lamp provided with a mirror. The lamp provided with a mirror includes a discharge lamp including a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively; and a reflecting mirror for reflecting light emitted from the discharge lamp and having a front opening for emitting the reflected light. The lamp provided with a mirror is formed so as to have a non-airtight structure. The house includes a transmission window made of a material for transmitting light emitted from the front opening and positioned forward in the emission direction of the front opening of the reflecting mirror.