Mirror unit and image capturing apparatus

A device comprising:

• a movable mirror drive section that accumulates a bias force using a drive force of a drive force source, and causes a movable mirror to pivot between an observation position and a withdrawn position by releasing the accumulated bias force;
• an attachment drive section that accumulates bias force using the drive force of the drive force source, and drives a working section other than the movable mirror with a predetermined timing relative to the back and forth pivoting of the movable mirror by releasing the accumulated bias force;
• an interlocking section that interlocks with the movable mirror and the attachment drive section, accumulates the bias force in the attachment drive section while the movable mirror drive section releases the bias force, and releases the bias force from the attachment drive section while the movable mirror drive section accumulates the bias force;
• a light blocking wall that surrounds a periphery of the movable mirror and limits light incident to the movable mirror;
• a light blocking plate that moves between an open position, at which an opening formed in the light blocking wall is not blocked, and a closed position, at which the light blocking plate blocks the opening;
• a focus sensor that is disposed such that when the light blocking plate has moved to the open position, the focus sensor is exposed to the movable mirror through the opening;
• and
• an image capturing section that captures image light incident to the mirror unit.

An image capturing apparatus comprising:

• a movable mirror that pivots between an observation position and a withdrawn position;
• a movable mirror drive section that accumulates bias force using drive force of a drive force source, and causes the movable mirror to pivot between the observation position and the withdrawn position by releasing the accumulated bias force;
• an attachment drive section that accumulates bias force using the drive force of the drive force source, and drives a working section other than the movable mirror with a predetermined timing relative to the back and forth pivoting of the movable mirror by releasing the accumulated bias force;
• an interlocking section that interlocks with the movable mirror and the attachment drive section, accumulates bias force in the attachment drive section while the movable mirror drive section releases bias force, and releases bias force from the attachment drive section while the movable mirror drive section accumulates bias force;
• a light blocking wall that surrounds a periphery of the movable mirror and limits light incident to the movable mirror;
• a light blocking plate that moves between an open position, at which an opening formed in the light blocking wall is not blocked, and a closed position, at which the light blocking plate blocks the opening;
• and
• an image capturing section operable to capture light incident to the movable mirror.