Lamp device and projector equipped with the same

Abstract

Aspects of the invention can provide a lamp device that is capable of avoiding concentration of stresses in a sub-mirror fixing portion of an arc tube. The lamp device can include an arc tube provided with a bulb portion encapsulating inside a pair of electrodes, and a pair of sealing portions formed continuously from the bulb portion and sealing inside electrode axes having the electrodes at tip ends and conductor foils to bring the electrode axes into conduction, a main reflection mirror, to which the sealing portion is fixed, to reflect lights emitted from the arc tube toward an illuminated region, and a sub-mirror fixed to the sealing portion in such a manner that a reflection surface opposes the main reflection mirror with the bulb portion in between. The sub-mirror can be bonded with a bonding agent to a surface region of the sealing portion present in a direction moving away from the bulb portion in reference to a position corresponding to a termination of the electrode axis.

1 . A lamp device, comprising: 
 an arc tube provided with a bulb portion sealing inside a pair of electrodes, and a pair of sealing portions formed continuously from the bulb portion and sealing inside electrode axes having the electrodes at tip ends and conductor foils to bring the electrode axes into conduction;    a main reflection mirror, to which one of the pair of sealing portions is fixed, that reflects light emitted from the arc tube toward an illuminated region;    a sub-mirror, disposed on the other one of the pair of sealing portions in such a manner that the bulb portion is between the sub-mirror and the main reflection mirror, that returns light emitted from the bulb portion to the main reflection mirror; and    the sub-mirror being bonded with a bonding agent to a surface region of the sealing portion present in a direction moving away from the bulb portion in reference to a position corresponding to a termination of the electrode axis.    
   
   
       2 . The lamp device according to  claim 1 , 
 the sub-mirror including a cup-shaped reflection base portion on which the reflection surface is formed, and a cylinder portion extending from the reflection base portion in an opposite direction of a reflection direction of the reflection surface in such a manner that the sealing portion is inserted therein; and    the sub-mirror being fixed to the sealing portion by utilizing a terminal portion of the cylinder portion.    
   
   
       3 . The lamp device according to  claim 2 , 
 the cylinder portion being located inside virtual lines linking an outermost portion of the reflection base portion and a tip-end outside portion of the sealing portion to which the cylinder portion is fixed.    
   
   
       4 . A projector, comprising: 
 a light source;    a light modulation device that forms an image by modulating a light emitted from the light source according to image information;    a projection lens that projects the image; and    the projector being characterized in that the lamp device according to  claim 1  is used as the light source.