To provide a high pressure discharge lamp capable of improving color temperatures suitable for color reproducibility of image projection, although it contains practically no mercury.
In the discharge lamp which is lighted with power of 80 W or more when it is stable, a pair of electrodes 151, 152 disposed face to face in a transparent bulb made of transparent quart glass is provided, coils 161, 162 are wound around the respective tips of them, and the distance between the electrodes is 3.5 mm or less. The discharge lamp contains a first halogen metal containing at least one of Dy, Nd, Sc, and In, a second halogen metal containing at least Zn, a noble gas with 3 atms or higher, and practically no mercury. The content of the first halogen metal is not less than 1.0×10-3 mg/mm3 and not more than 6.0×10-3 mg/mm3, and the content of the second halogen metal is not less than 6.0×10-3 mg/mm3 and not more than 16.0×10-3 mg/mm3.
TANAKA ICHIRO
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