BACKGROUND OF THE DISCLOSURE

Field of the Disclosure

The present disclosure relates to a lens barrel having a circuit component that constitutes a power supply within a barrel. Specifically, the present disclosure relates to a lens barrel applied to an image pickup apparatus such as a digital still camera and a digital video camera

Description of the Related Art

An ultrasonic wave motor may be mounted on an optical device such as a digital camera, a video camera, and an exchangeable lens to increase speed of an autofocus function and achieve quiet performance.

A power supply for driving the ultrasonic wave motor requires a circuit component (hereinafter referred to as a booster transformer) that boosts a voltage supplied thereto and that applies a desired alternating voltage to the ultrasonic wave motor.

Meanwhile, leakage magnetic flux from the booster transformer becomes a cause of magnetic noise. Magnetic noise may be superimposed on image pickup signals and thus degrade image quality.

Thus, for such an optical device, reduction of magnetic noise is required to increase sensitivity and achieve higher image quality of an image pickup device mounted on the optical device.

Japanese Patent Application Laid-Open No. 2013-179787 discusses a driving device in which a booster unit is arranged at a position different from a position of a holding substrate, on which a control unit and a switching unit are mounted, to bring the booster unit close to a vibration actuator.

This configuration can shorten wiring for high voltage driving signals flowing between the booster unit and the vibration actuator and thus can curb the influence of leakage magnetic flux.

However, in the configuration discussed in Japanese Patent Application Laid-Open No. 2013-179787, the booster transformer required as the power supply for driving the vibration actuator is arranged outside a cam barrel, which is a driven member.

The booster transformer typically has a magnetic circuit such as a coil therein and has a relatively large outer shape as a circuit component. Thus, arranging the booster transformer outside the cam barrel may upsize the optical device.

SUMMARY OF THE DISCLOSURE

The present disclosure is directed to providing a lens barrel, in which a circuit component constituting a power supply can be arranged on a side surface of the lens barrel that moves in accordance with rotation of a cam barrel.

According to an aspect of the present disclosure, a lens barrel includes an image pickup optical system configured to form an object image on an image pickup device, a cam barrel configured to rotate around an optical axis of the image pickup optical system for driving a first lens that constitutes the image pickup optical system, a barrel that is configured to hold the first lens and to be cam-engaged with the cam barrel and that is arranged on an inner circumference side of the cam barrel, and a circuit component that is arranged on the inner circumference side of the cam barrel and constitutes a power supply for an actuator. The circuit component is arranged on a side surface of the barrel. The circuit component is configured to move in a direction of the optical axis together with the barrel in accordance with the rotation of the cam barrel.

Further features and aspects of the present disclosure will become apparent from the following description of example embodiments with reference to the attached drawings.

