Foreign substance removing apparatus
AssigneeCanon Kabushiki Kaisha
InventorKosuke Fujimoto
Life of this patent
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Abstract
A foreign substance removing apparatus that can provide the desired vibration amplitude to a light transmitting member, without using a large driving voltage. The foreign substance removing apparatus removes foreign substances adhered to a surface of an optical member disposed in a light ray incident path and includes a piezoelectric element fixed to a first plane of the optical member, a circular disk fixed to a second plane, opposite from the first plane, of the optical member so as to face the piezoelectric element, and a driving unit for applying an AC voltage to the piezoelectric element to cause the optical member to elastically vibrate in a direction perpendicular to the planes thereof, thereby removing the foreign substances adhered to the surface of the optical member.
Claims6
A foreign substance removing apparatus for removing foreign substances adhered to a surface of a plate-like light transmitting member disposed in a light ray incident path, comprising:
- an electromechanical energy conversion element bonded to a first plane of said light transmitting member;
- an elastic member bonded to a second plane of said light transmitting member so as to face said electromechanical energy conversion element, the second plane being opposite from the first plane, said elastic member enabling a bending neutral surface to be maintained inside of said light transmitting member by compensating for an amount of increase in rigidity due to said electromechanical energy conversion element being bonded to said light transmitting member;
- and
- an AC voltage applying circuit for applying an AC voltage to said electromechanical energy conversion element to cause said light transmitting member to elastically vibrate in a direction perpendicular to the planes thereof, thereby removing the foreign substances adhered to the surface of said light transmitting member;
- wherein
- said elastic member has a thickness thereof made smaller than that of said electromechanical energy conversion element when said electromechanical energy conversion element has its Young's modulus smaller than that of said elastic member so that said elastic member enables the bending neutral surface to be maintained of said light transmitting member.
Dependencies are inferred from the claim text.