Lens barrel having a piezoelectric actuator for moving optical elements
AssigneeMinolta Co., Ltd.
InventorsMasayuki Ueyama, Minoru Kuwana, Hideki Nagata
Life of this patent
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Abstract
The present invention discloses a lens barrel moving an optical system by a linear actuator using a piezoelectric element. The actuator is provided with the constitution whereby a driving member is driven by an extension displacement and a contraction displacement having different velocities caused by applying drive pluses to the piezoelectric element and a driven member frictionally connected to the driving member is linearly moved. The focusing operation is conducted by moving the optical system directly in the optical axis direction by the linear actuator.
Claims21
A lens barrel performing a focusing operation by moving a lens in an optical axis direction by means of an actuator in the lens barrel, said lens contributing to the focusing operation among a plurality of lenses, said actuator comprising:
- a piezoelectric element;
- a moving member holding the lens contributing to the focusing operation and connected to the piezoelectric element for moving the lens contributing to the focusing operation in the optical axis direction by a displacement caused in the piezoelectric element;
- and
- a supporting unit supporting the piezoelectric element and the moving member;
- wherein said supporting unit is arranged along the optical axis direction and an end portion of the supporting unit in the optical axis direction has a shape which is inclined such that a height of the end portion decreases from an inner side of the supporting unit toward an outer side thereof.
A lens barrel performing a focusing operation by moving a lens in an optical axis direction by means of an actuator in the lens barrel, said lens contributing to the focusing operation among a plurality of lenses, said actuator comprising:
- a piezoelectric element;
- a moving member holding the lens contributing to the focusing operation and connected to the piezoelectric element for moving the lens contributing to the focusing operation in the optical axis direction by a displacement caused in the piezoelectric element;
- and
- a supporting unit supporting the piezoelectric element and the moving member;
- wherein said supporting unit is arranged along the optical axis direction and an end portion of the supporting unit in the optical axis direction has an approximately semicircular shape.
A lens barrel performing a focusing operation by moving a lens in an optical axis direction by means of an actuator in the lens barrel, said lens contributing to the focusing operation among a plurality of lenses, said actuator comprising:
- a piezoelectric element;
- a moving member holding the lens contributing to the focusing operation and connected to the piezoelectric element for moving the lens contributing to the focusing operation in the optical axis direction by a displacement caused in the piezoelectric element;
- a drive circuit causing the displacement in the piezoelectric element;
- and
- a film type electric wiring electrically connecting the piezoelectric element to the drive circuit;
- wherein said electric wiring is arranged such that a film face thereof at a position crossing the optical path in the lens barrel is in parallel with said optical path to minimize a portion of the optical path blocked by the electric wiring.
A reflection type lens barrel projecting a light from an object incident on the lens barrel via a lens on an image plane by reflecting the light by a primary mirror and a secondary mirror, said lens barrel comprising in the lens barrel:
- a piezoelectric element;
- a drive circuit causing a displacement in the piezoelectric element;
- a secondary mirror moving member holding a secondary mirror for moving said secondary mirror in an optical axis direction by the displacement of the piezoelectric element caused by driving the drive circuit, said secondary mirror moving member being connected to the piezoelectric element;
- and
- a supporting unit integrally supporting the piezoelectric element and the secondary mirror moving member;
- wherein in said supporting unit, the piezoelectric element is arranged on an object side and the secondary mirror moving member is arranged on an image plane side along the optical axis direction and an end of the supporting unit on the image plane side in the optical axis direction is formed in an inclined shape such that an optical path whereby the light from the object reflected by the primary mirror reaches the secondary mirror is not blocked.
Dependencies are inferred from the claim text.