Abstract: In an optical pickup device for recording information onto and/or reading out information from an optical recording medium, comprising a light beam source for generating a light beam to be projected toward the optical recording medium, and a light beam detector for receiving the light beam reflected by the optical recording medium so that the information is read out from the light beam after reflected by the optical recording medium, a container houses therein the light beam source and includes an aperture through which the light beam proceeds toward the optical recording medium, and a light beam guide member is mounted on an outer surface of the container and covers the aperture to guide the light beam after reflected by the optical recording medium toward the light beam detector.

Abstract: An optical pickup device has a single light beam path in which at least one or either of a plurality of kinds of light beams (different from each other in, for example, wavelength) for respective recording densities and/or recording-medium-thicknesses proceeds toward a surface of an optical recording medium and proceeds to a light beam detector after being reflected by the surface.

Abstract: An optical pickup device has a single light beam path for common use in treating or passing either of a plurality of kinds of light beams for respective recording densities and/or recording-medium-thicknesses different from each other, in other words, at least one or either of the plurality of kinds of light beams is introduced into the common single light beam path which may includes a single quarter-wave plate and/or single collimator and/or single objective.

Abstract: In an optical pickup, an optical guide member is provided in an optical path of light from a light source, and has a plurality of inclined surfaces inclined with respect to a light beam emitted from the light source. A light-receiving element is provided for receiving light and for converting the received light into an electrical signal. The optical guide member and the light-receiving element are contained in a packaging member. The light beam from the light source is reflected by the plurality of inclined surfaces of the optical guide member, and then are directed to a recording medium. The reflected light from the recording medium is directed to the light-receiving element. At least one of dry air and inert gas such as nitrogen gas is charged in the interior of the packaging member at a pressure of 0.5 atm to 1.5 atm, thereby preventing the optical characteristics from being degraded.