Patent ID: 7656570
Filing Date: 2010-02-02
Classification: G02B

Abstract:
1. An optical deflector, comprising: a supporting member; a first movable element having a light deflecting element; at least one second movable element; at least one first torsion spring configured to support said first and second movable elements, for torsional oscillation about an oscillation axis; at least one second torsion spring configured to support said second movable element and said supporting member, for torsional oscillation about the oscillation axis; and a driving system configured to apply a driving force to at least one of said first and second movable elements; wherein said optical deflector has at least two natural oscillation modes of different frequencies; wherein a moment of inertia of said second movable element with respect to said oscillation axis is larger than a moment of inertia of said first movable element with respect to said oscillation axis, wherein a length of said second movable element in a direction perpendicular to the oscillation axis is equal to or less than a length of said first movable element in a direction perpendicular to the oscillation axis, and wherein only said second movable element has a permanent magnet.