| 摘要 |
PURPOSE:To easily increase the power at the time of macrophotography by extending a 1st lens group by more than the extension quantity of focus adjusting operation. CONSTITUTION:When a zoom ring 10 is rotated, a 1st holding frame moves forth and a swing arm 26 rotates a lock gear 32 about a support shaft 26c through a rotary intermediate gear 34. Consequently, the claw part 38b of a lock lever 38 abutting on the lock gear 32 engages a lock gear 32c to stop further rotation. When the swing arm 26 stops rotating, a 2nd holding frame 22 abutting on the 2nd cam surface 26b is stopped from moving further forth. When the zoom ring 10 is rotated continuously, only the 1st holding frame 20 moves forth while the 2nd holding frame 22 stops. Macrophotography is therefore possible over the entire range from the wide angle photography to the telephotography. |
