TUBUS FUER EIN ZOOMOBJEKTIV

摘要

A zoom lens barrel has front and rear lens groups (A, C) for zooming and central lens group (B) for focussing and a cam ring with two cam grooves (14a, 14b) for lens groups (A and B) which has a zooming section (???1) and a lens accommodation section (???2) and which rotates to control the position of the lens groups. Two lens groups (A and C) move together in the zooming section via engaging portions (23a, 30a). Portions (30a, 23a) are disengaged when rollers (C') reach bottom of guide groove (18c) so that in the lens accommodation section the front lens group (A) and central lens group (B) come close to the rear lens group (C) and thus decrease the overall length of a zoom lens in a compact camera. There is also disclosed a barrier mechanism (Figs. 7 and 8) of the lens barrel including a pair of barrier plate assemblies which open and close an opening of the lens barrel. <IMAGE>