A liquid crystal element is provided as a polarization plane rotating device between a laser beam source and a beam splitter. Light emitted from the laser beam source passes through the liquid crystal element and the beam splitter, and is converted into parallel light by a collimating lens. The collimated light is incident on a first light-selection device, is reflected at a flat first reflecting surface or a concave second reflecting surface, and is then incident on a super-resolution cut-off filter as a second light-selection device. The light having passed through the second light-selection device is incident on an objective lens, and is converged onto a recording surface. The selection of the reflecting surface of the first light-selection device is determined based on an operation mode of the liquid crystal element.

 
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> Information recording medium and method for producing the same, and method for recording/reproducing information thereon

> Medical laser apparatus

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