Light source device

The present invention addresses a high luminance light source device having discharge lamp, a low saturation voltage flowing through the lamp current becomes large. The light source apparatus according to the present invention comprises a pair of opposed electrodes disposed so that the discharge lamp and the discharge lamp after the start of work, the power supply device to provide a discharge current to the electrodes, both connected to each other, wherein said power supply means for controlling flow through the discharge lamp the current does not exceed a predetermined current limit value, immediately after initiation of starting of the discharge lamp to heat the discharge lamp reaches the said current limit value as a first limit value, after the above-described current limit value changes the time period before the full It is smaller than the first limit value of the second limit value.