Optical head device
AssigneesCanon Kabushiki Kaisha, Canon Denshi Kabushiki Kaisha
InventorsTetsuro Kuwayama, Shigeyuki Suda, Yasuo Nakamura
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Abstract
An optical head device comprising a light source unit, a deflecting element for changing the direction of travel of a light beam emitted from the light source unit, and a condensing element for condensing the light beam on a recording medium. A movable portion is formed so that the deflecting element and the condensing element move substantially together with each other relative to the recording medium, and the deflecting element is designed such that the variation in direction of the emergent light beam from the movable portion caused by the rotative displacement of the movable portion with respect to at least one axis can be decreased.
Claims5
An optical head device comprising a light source unit, deflecting means for varying the direction of travel of a light beam emitted from said light source unit, condensing means for condensing the light beam from said deflecting means on a recording medium, and moving means for moving said deflecting means and condensing means relative to said recording medium, said deflecting means consisting of plural reflecting surfaces having a predetermined fixed angle therebetween and said fixed angle being set so that the variation of an angle in the direction of the light beam from said deflecting means to said condensing means, resulting from rotative displacement of said deflecting means with respect to at least one axis, be extinguished.
An optical head device comprising a fixed light source unit, deflecting means for varying the direction of the light beam from said light source unit, condensing means for condensing the light beam from said deflecting means on a recording medium, a housing for holding said deflecting means and said condensing means, and means for moving said housing relative to said recording medium, said deflecting means consisting of plural reflecting surfaces having a predetermined fixed angle therebetween and said fixed angle being set so that the axis of the light beam travelling from said deflecting means to said condensing means is always maintained perpendicular to the recording medium irrespective of rotative displacement of said deflecting means with respect to at least one axis.
Dependencies are inferred from the claim text.