| 摘要 |
PROBLEM TO BE SOLVED: To favorably correct defocus of a lens system caused by ambient temperature change with a simple correcting mechanism in a zoom lens device.SOLUTION: A zoom lens device 1 includes a focusing system lens 2 arranged on a subject side and a variator system lens 3 next thereto, and also includes a temperature sensor 10. The focusing system lens 2 includes a focusing lens 2B, and a temperature-based correction lens 2A for correcting a change in a focal point caused by temperature of the focusing system lens 2. The temperature-based correction lens 2A is moved by a temperature-based correction lens driving mechanism 11 along an optical axis to a position which is determined by temperature detected by the temperature sensor 10, independently of the position of the focusing lens 2B or the position of the variator system lens 3. |
