Patent ID: 6456445
Filing Date: 2002-09-24
Classification: G02B

Abstract:
A zoom lens comprising:a cam barrel driven to rotate about an optical axis; a first cam groove and second cam groove formed on an inner peripheral surface of said cam barrel, said first cam groove and second cam groove having different profiles; a first lens frame having a first cam follower which is engaged with said first cam groove; and a second lens frame having a second cam follower which is engaged with said second cam groove; wherein said first cam groove comprises: a first zoom section for moving said first lens frame between a telephoto position thereof and a wide-angle position thereof in accordance with a rotation of said cam barrel; a first leading section for leading said first cam follower from a first cam follower insertion opening, which is open at an end of said cam barrel, to said first zoom section; and a cam dead end positioned on the opposite side of said first zoom section with respect to said first leading section, wherein said first cam follower does not enter said cam dead end during operation of said zoom lens; wherein said second cam groove comprises: a second zoom section for moving said second lens frame between a telephoto position thereof and a wide-angle position thereof in accordance with said rotation of said cam barrel; and a second leading section for leading said second cam follower from a second cam follower insertion opening, which is open at an end of said cam barrel, to said second zoom section; wherein said cam dead end of said first cam groove and said second cam follower insertion opening of said second cam groove are formed at the same circumferential position in a circumferential direction of said cam barrel, and wherein, upon assembly of said first lens frame and said second lens frame to said cam barrel, said first cam follower is inserted into said first leading section via said first cam follower insertion opening, and subsequently, said second cam follower is inserted into said second leading section via said second cam follower insertion opening.