| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a front converter equipped with a vibration-proof function attached to the object side of an underwater camera, for example, having a wide angle function and capable of correcting the positional fluctuation of an image caused by the shake of the camera. SOLUTION: This front converter FC whose afocal magnification is smaller than 0.9 is freely detachably attached to the object side of an objective lens used in an ambient medium whose refractive index is substantially larger than 1.0. At least the surface of the front converter FC which is the most proximate to the object side comes into contact with the ambient medium, and the front converter FC is equipped with a displacing means 1 for displacing a part of a lens group GL out of an optical system constituting the front converter FC in a direction nearly orthogonally crossed with an optical axis in order to correct the positional fluctuation of the image formed through the objective lens.</p> |
