Patent ID: 7656596

Claim:
A lens apparatus comprising: a fixed lens-barrel including a plurality of fixed-side first guide grooves extended straight and which are formed on an outer peripheral surface in parallel to each other and a plurality of second guide grooves extended straight and which are formed on an inner peripheral surface in parallel to each other; a first movable lens-barrel to hold a first lens at the outside of said fixed lens-barrel and which includes a plurality of movable-side first guide grooves extended straight, said plurality of movable-side first guide grooves being opposed to said fixed-side first guide grooves with a predetermined gap in parallel to each other; a second movable lens-barrel to hold a second lens of which optical axis is coincident with that of said first lens at the inside of said fixed lens barrel and which includes a plurality of movable-side second guide grooves extended straight, said plurality of movable-side second guide grooves being opposed to said fixed-side second guide grooves with a predetermined gap in parallel to each other; more than two first rolling element units including a plurality of rolling elements being provided between said fixed-side first guide grooves and said movable-side first guide grooves so as to become able to freely roll and which supports said first movable lens-barrel to said fixed lens-barrel such that said movable lens-barrel can be moved in the optical axis direction of said lens; and more than two second rolling element units including a plurality of rolling elements provided between said fixed-side second guide grooves and said movable-side second guide grooves so as to become able to freely roll and which supports said second movable lens-barrel to said fixed lens-barrel such that said second movable lens-barrel can be moved in the optical axis direction of said lens, wherein said first and second movable lens-barrels are supported to said fixed lens-barrel such that they can be independently moved in the optical axis directions of said first and second lenses.