METAL HALIDE LAMP

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PROBLEM TO BE SOLVED : To suppress occurrence of chromaticity change and crack leak, in a condition where mercury is not essentially included in a discharge space. SOLUTION : A discharge medium comprising a metal halide and a rare gas without containing mercury is enclosed in a discharge space 111 of a translucent airtight container 1 having sealing parts 121 and 122 formed at both ends of an arc tube part 11 for forming the discharge space 111. Metal foil pieces 21 and 22 are sealed in the sealing parts 121 and 122; a pair of electrodes 31 and 32 arranged oppositely to each other in the discharge space 111 are connected to one-side ends thereof; and, at ends on the sides of the metal foil pieces 21 and 22 of the electrodes 31 and 32, coils 41 and 42 are mounted in the direction of the discharge space 111 so as to contact peripheries thereof. When it is assumed that the length from ends on the discharge space 111 side of the coils 41 and 42 to boundaries between the sealing parts 121 and 122 and the arc tube part 11 is L, a relationship of 1 mm≤L≤5 mm is satisfied.