High-voltage discharge lamp, lamp unit, projection image display device, and method for manufacturing high-voltage discharge lamp

A high-pressure discharge lamp comprising:

• a glass arc tube including a light-emitting part and a sealing part connected to the light-emitting part, the light-emitting part enclosing a discharge space;
• a pair of electrodes, one end of each of the electrodes facing one end of the other electrode in the discharge space;
• and
• a metal foil embedded in the sealing part with the other end of each electrode connected thereto, wherein
• the metal foil includes at least one projection.

A method of manufacturing a high-pressure discharge lamp, the method comprising the steps of:

• (a) preparing a glass including a light-emitting part and a sealing part connected to the light-emitting part, the light-emitting part enclosing a discharge space;
• (b) preparing an electrode provided with a main body and a rod-shaped part having high melting-point metallic particles interspersed on a surface thereof, the metallic particles having been treated with an acidic solution;
• (c) inserting the rod-shaped part into the sealing part so that the main body protrudes into the light-emitting part;
• and
• (d) sealing the rod-shaped part by fusing and then pressure welding the sealing part.