To prevent autofocus operation time from getting longer depending on ambient temperature.
A drive module has drive modes such as: a first drive mode in which, after a focal point is searched by moving a lens frame across an entire range of movement by energizing a shape memory alloy body and gradually increasing its temperature, the temperature of the shape memory alloy body is decreased to move the lens frame to a focusing position; and a second drive mode in which, after the focal point is searched by moving the lens frame across the entire range of movement by energizing the shape memory alloy body and gradually decreasing its temperature, the temperature of the shape memory alloy body is increased to move the lens frame to the focusing position. A control means detects the ambient temperature, selects the first drive mode if the ambient temperature is lower than threshold temperature, selects the second drive mode if the ambient temperature is higher than the threshold temperature, and controls energizing of the shape memory alloy body according to the selected drive mode, to allow driving of a drive means.
NOBE TETSUYA
Noriaki Uchino
Nobuyuki Kimura
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