Light amount adjusting apparatus, lens barrel, and imaging apparatus

A lens barrel having a light amount adjusting apparatus,

• wherein the light amount adjusting apparatus comprises:
• a base member having an opening formed therein;
• a driving source having a rotary shaft to which a first contact part is fixed;
• a blade driving member that has a second contact part which is adapted to contact with the first contact part and to which a driving force from the driving source is transmitted and a plurality of first blade engaging parts formed around the circumference of the opening and is pivotally joined to the base member in the circumferential direction of the opening;
• and
• a plurality of light amount adjusting blades which is arranged around the circumference of the opening and each having a second blade engaging part which is adapted to engage with the first blade engaging part,
• wherein the base member has a plurality of supporting parts for supporting the plurality of light amount adjusting blades which is arranged around the circumference of the opening and the second contact part is located outside a circle extending through the plurality of supporting parts,
• wherein the contact part between the second contact part and the first contact part is constituted at the other surface of the base member with respect to a surface having a jointing part between the blade driving member and the base member, and
• wherein, when the blade driving member is pivoted in the circumferential direction of the opening, a part of the blade driving member overlaps at least one of the supporting parts for supporting the light amount adjusting blades at a position offset in a direction parallel to the center axis of the opening.

An imaging apparatus having a light amount adjusting apparatus,

• wherein the light amount adjusting apparatus comprises:
• a base member having an opening formed therein;
• a driving source having a rotary shaft to which a first contact part is fixed;
• a blade driving member that has a second contact part which is adapted to contact with the first contact part and to which a driving force from the driving source is transmitted and a plurality of first blade engaging parts formed around the circumference of the opening and is pivotally joined to the base member in the circumferential direction of the opening;
• and
• a plurality of light amount adjusting blades which is arranged around the circumference of the opening and each having a second blade engaging part which is adapted to engage with the first blade engaging part,
• wherein the base member has a plurality of supporting parts for supporting the plurality of light amount adjusting blades which is arranged around the circumference of the opening and the second contact part is located outside a circle extending through the plurality of supporting parts,
• wherein the contact part between the second contact part and the first contact part is constituted at the other surface of the base member with respect to a surface having a jointing part between the blade driving member and the base member, and
• wherein, when the blade driving member is pivoted in the circumferential direction of the opening, a part of the blade driving member overlaps at least one of the supporting parts for supporting the light amount adjusting blades at a position offset in a direction parallel to the center axis of the opening.