OPTICAL APPARATUS

Provided is an optical apparatus having good lens positioning accuracy and excellent optical performance.The optical apparatus includes a straight-proceeding barrel configured to move on a lens group in an optical axis direction and a guide barrel having a guide groove part configured to guide the movement of the straight-proceeding barrel in the optical axis direction. In the guide groove part, a first guide groove part is formed in the optical axis direction so as to have a bottom on an outer diameter side, and a second guide groove part is formed in the optical axis direction as a through hole from the outer diameter side to an inner diameter side. The first guide groove part and the second guide groove part are connected to each other and have respective use regions configured to partially overlap each other in the optical axis direction.