| 摘要 |
<p>PURPOSE:To easily self-correct time at a low cost by correcting the display time to a reference time, when it is detected that the present time is the reference time determined in advance by an input value from a control solar battery. CONSTITUTION:Sunshine to each control solar battery 103 - 105 is shut off at each different time which tunes with a motion of the sun by a light shielding member 106. Therefore, an output PB of the solar battery 104 placed in the center takes the minimum value at a transit time t0, and each output PA, PC of the solar batteries 103, 105 placed on both its sides takes the minimum value at about the same time of the transit time t0. A time correcting device 312 detects each output PA(t) - PC(t) of the solar batteries 103 - 105, monitors one or both values of PB(t)/PA(t) and PB(t)/PC(t), and when one or both values of PB(t)/PA(t) and PB(t)/PC(t) become a threshold or below, it is decided that the time of t0 and a control signal 313 for setting a display time of a time display part 101 as t0 is outputted and a time correction is executed.</p> |
