OPTICAL ELEMENT, AN ABERRATION COMPENSATING ELEMENT, A CONDENSING ELEMENT, AN OBJECTIVE LENS SYSTEM, AN OPTICAL PICKUP DEVICE, AND AN OPTICAL INFORMATION RECORDING/REPRODUCING DEVICE, SPECIALLY RELATED TO REDUCING OPTICAL PARTS TO THE MAXIMUM BY COMMONLY USING AN OPTICAL SYSTEM FOR A HIGH DENSITY DISK AND AN OPTICAL SYSTEM FOR A CD

摘要

PURPOSE: An optical element, an aberration compensating element, a condensing element, an objective lens system, an optical pickup device, and an optical information recording/reproducing device are provided to include a high-density optical disk employing a bluish-purple laser light source and a DVD, and to properly record and/or reproduce information on plural optical information recording media using different wavelengths. CONSTITUTION: An optical element for an optical pickup device comprises as follows. The first optical surface is made of concentric circles at an optical axis, and is in overlay diffracted scheme including plural circular bands configured in plural stepwise structures. The second optical surface is made of concentric circles at an optical axis, and is in diffracted scheme including plural circular bands divided by each step difference in order to generate diffracted rays of a diffracted order where an absolute value is not smaller than 1 with regards to a light velocity.