| 摘要 |
PURPOSE:To perform monitoring operation effectively, by detecting the signal generated in the 1st image pickup mode of a pyroelectric type image pickup device, controlling the rotation of a chopper disposed on the front surface of the pyroelectric image pickup device in accordance with the detected signal and converting the mode to the 2nd image pickup mode. CONSTITUTION:If there is an abrupt change in the movement of an object having a certain temp. or the temp. of a still object in front of a photographic lens, an instantaneous electric signal 17 corresponding to said change is outputted by a waveform circuit 5 in a signal processing circuit. The signal is applied as a trigger signal 17 for changing over of image pickup modes to a change-over circuit 13 for image pickup modes. A logical circuit operates so as to shift the 1st image pickup mode (panning mode) to the 2nd image pickup mode (chopper mode). The output of the circuit 13 is applied to a chopper driving motor 14, which rotates a chopper 15 to a chopper mode. The camera is monitored in the panning mode and when the change in the temp. state arises, the panning mode is changed over to the chopper mode in parallel with alarming; therefore, the efficiency in the monitoring operation is improved, the deterioration in the chopper mechanism is prevented and the electric power consumption for driving the chopper is reduced. |
