| 摘要 |
PURPOSE:To reduce the deterioration in the S/N of a picture output signal due to the increase in a dark current at an external temperature, by placing a solid- state image pickup element and a part of a cooling means in a cavity and evacuate the cavity. CONSTITUTION:A thermal conduction shaft 8 is operated to contact a heat sink 11 on a semiconductor fitting base 2, allowing to dissipate heat sufficiently from a semiconductor base 1 provided with a CCD. The heat sink 11 is detached from the base 2. Since the cavity 13 is in this state, the bases 1, 2 are interrupted from the surrounding thermally almost completely. The CCD is exposed and picture information is read out. Since the time required for the readout is one frame period, the power application is performed during this period only, then the self-heating of the CCD is minimized. In operating a CCD camera several times, the temperature of the base 1 is increased due to the self-heating and a dark current level is increased, then the heat sink 11 is contacted on the base 2 for the heat dissipation. Thus, the deterioration in the S/N of a picture output signal is reduced and the picture having high resolution is obtained. |
