Abstract: An optical pickup device includes a beam shaping mirror. The mirror has a first optical surface on which a wavelength selection film is formed and a second optical surface on which a diffraction grating is formed. The wavelength selection film transmits a first laser beam and reflects a second laser beam. Light intensity distribution of the first laser beam is converted from an elliptic shape to a circular shape by reflecting the first laser beam transmitted by the wavelength selection film and input to the beam shaping mirror by the diffraction grating, then transmitting it by the wavelength selection film and outputting it from the beam shaping mirror. The diffraction grating diffracts the first laser beam in order that directions of the first and second laser beams which are output from the beam shaping mirror become the same.

Abstract: An optical pickup device in which light via a beam shaping mirror is input to an objective lens and the light is directed to an optical disc, includes a collimator lens which changes the light input to the beam shaping mirror into infinite system light and the beam shaping mirror includes a diffraction grating which changes the infinite system light into finite system light.

Abstract: An optical pickup device for reducing comma aberration, spherical aberration, and astigmatism while entering a beam light having an ideal intensity distribution to the objective lens is provided. In an optical pickup device for emitting beam lights having different wavelengths from light sources, transmitting the beam lights through a common collimator lens and an objective lens and irradiating the beam lights onto an optical disc, one of the beam lights is converted to an infinite light and exit from the collimator lens, and the other beam light is converted to a finite light and exit from the collimator.

Abstract: An optical pickup device includes a plurality of light sources for emitting light beams having different wavelengths; an objective lens for focusing the light beams emitted from the light sources on a recording surface of an optical recording medium; and a photo detector for receiving the light beams reflected from the recording surface.