An optical pickup for reading out information from an information recording medium, such as an optical diskette, comprises a light source (11) for irradiating a light beam (L,) onto an optical diskette (D), an optical sensor (15) for detecting a light beam (L 10 ) reflected from the optical diskette, and an optical system including a wave plate and two hologram lenses (12,13). The first hologram lens (13) diffracts the light beam (L 7 ) from the light source, and the second hologram lens (12) transmits the same light beam (L 7 ). On the other hand, the second hologram lens (12) diffracts the reflected light beam (L 10 ) from the optical diskette (D) towards the optical sensor (15), and the first hologram lens (13) transmits the same reflected light beam. (L 10 ). The light and compact- sized hologram lenses (12,13) enable a reduction in the access time to the optical diskette (D).
A hologram lens assembly, suitable for use in an optical pickup, is also disclosed.