OPTICAL HEAD FOR OPTICAL CARD RECORDING AND REPRODUCING DEVICE

• Main Author: KAWAGUCHI BUNRO
• Format: Patent
• Language: English
• Published: 05.10.1988
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

PURPOSE:To obtain an inexpensive optical head for an optical card recording and reproducing device by using one and the same lens for a collimeter lens and an objective lens. CONSTITUTION:The titled optical head is provided with a semiconductor laser 11, a 1st optical means 2 converting a light beam radiated from the semiconductor laser 11 into a parallel beam, a 2nd optical means 4 converging the parallel beam onto the information recording medium 82 of an optical card, and a detecting means 7 detecting the reflected laser beam from the medium 82. The 1st and 2nd optical means 2, 4 are constituted of the same optical system. The parallel planar plate 11 of the beam projecting window of the laser 11 and a transparent substrate 81 can be sufficiently corrected at their aberration by using the same lens, so that one and the same lens can be used for the collimeter lens and the objective lens. Consequently, the kind of components constituting the optical head can be reduced.