To suppress a deterioration of a non-heating type electronic component due to a heat generated from a heating type electronic component while a housing is reduced in size and weight and to suppress a deterioration of the heating type electronic component due to a heat storage in an electronic circuit module for discharge lighting, etc.

Barriers 8 used for thermal insulation are each formed of a magnesium alloy having a low thermal conductivity, a light weight and easy thinning, and hence the barriers 8 can be reduced in thickness and the weight. Further, even when the barriers 8 are thinned, a heat generated from a self-heating type electronic component 31 is shut off by the barrier 8, and the deterioration of the non-self-heating type electronic component 32 can be suppressed. Further, a hollow part 7 is provided in this barrier 8, and hence the heat transferred from the component 31 to the barrier 8 can be dissipated from the hollow part 7. Accordingly, the heat storage of the component 31 is prevented, and hence the deterioration of the component 31 can be suppressed.