Patent ID: 8247974
Filing Date: 2012-08-21
Classification: G03B,H01J

Abstract:
1. A high pressure discharge lamp comprising: an arc tube that includes: the enclosed mercury has a density of 0.2 to 0.4 [mg/mm3] inclusive, a distance W from a contact point S to a center O of the light-emitting part is 3.0 to 5.0 [mm] inclusive, where the contact point S represents a point where a tube axis Z of the arc tube intersects with an inner surface of the arc tube, a distance C the distance C a minimum thickness X [mm] of the arc tube in sealing part-side portions and a maximum outer diameter D [mm] of the light-emitting part satisfy a relation X/D≧0.2, the sealing part-side portions being portions of the light-emitting part that are close to the sealing parts.