ASTIGMATISM GENERATING OPTICAL ELEMENT, OPTICAL PICKUP INTEGRATED ELEMENT, OPTICAL PICKUP AND OPTICAL INFORMATION RECORDING AND REPRODUCING DEVICE

摘要

PROBLEM TO BE SOLVED: To correct astigmatism to be generated on an optical information record medium, etc., and to easily perform accurate positioning of the astigmatism generating optical element. ;SOLUTION: The astigmatism generating optical element 10 is equipped with two transparent optical members 11 and 13, each having a triangle pole shape and a transparent platelike optical member 12 disposed to be held by these two optical members 11 and 13 between them. A refractive index of the optical member 12 is different from refractive indexes of the optical members 11 and 13 respectively. Light from a light source is passed through the optical members 11 and 12, and is reflected by the surface of the optical member 12 on the side of the optical member 13 and passed through the optical members 12 and 11, and is given prescribed astigmatism and then emitted out of the astigmatism generating optical element 10.;COPYRIGHT: (C)1998,JPO