Binocular with rotation transmitting system

摘要

A binocular includes first and second swingable bodies respectively accommodating telescope systems. The binocular further includes two drive rings respectively provided to the swingable bodies and an operation knob. A transmission unit is provided to transmit the rotation of the operation knob to the drive rings. The transmission unit includes two pairs of a first gear and a second gear. The first gear and the second gear engage with the other so that a contact point of pitch circles thereof is located on each of the swing axis.