Optical head devices for use in disc players

Claim 1

An optical head device for use in a disc player comprising a movable optical assembly (23; 71; 71′) which has a finite-magnification objective lens (11), light reflecting means (45), and a light beam generating and detecting unit (43) containing a semiconductor substrate (50) provided with photodetecting means (51,52) and light beam generating means (53), said finite-magnification objective lens (11), light reflecting means (45) and light beam generating and detecting unit (43) being supported by a common supporting member (22; 80; 80′), and a driving mechanism (20,21a,21b,24; 72,74) for moving the movable optical assembly (23; 71; 71) in both a first direction along an optical axis of the finite-magnification objective lens (11) and a second direction substantially perpendicular to the first direction, characterized in that additional light reflecting means (44; 44′) is provided in the movable optical assembly (23; 71; 71′) so that a light beam generated by the light beam generating means (53) is reflected by the additional light reflecting means (44; 44′) to be changed in its traveling direction, reflected further by the light reflecting means (45) to be changed again in its traveling direction, and focused by the finite-­magnification objective lens (11) at a position on the optical axis of the finite-magnification objective lens (11), and a light beam coming from the outside of the movable optical assembly (23; 71; 71′) is received by the finite-magnification objective lens (11) to pass therethrough to the light reflecting means (45), reflected by the second light reflecting means (45) to be changed in its traveling direction, reflected further by the additional light reflecting means (44; 44′) to be changed in its traveling direction, and guided to the photodetecting means (51, 52) contained in the light beam generating and detecting unit (43).