| 摘要 |
PURPOSE: An optical recording/playback device with a near field is provided to shorten access time by reducing the weight and volume of an optical head, to promote easy servo control such as tracking and to inhibit error in action remarkably. CONSTITUTION: The optical recording/playback device with a near field includes an optical source(1), a photo detector(3) for converting reflected beam of a disk(2) into electric signals, a beam splitter(4) for splitting beam of the optical source, a collimating lens(5) for projecting the beam parallel from the beam splitter and a parabola lens(7) for transmitting the parallel beam of the collimating lens. In the parabola lens, a plane portion(7a) is formed on the upper portion of the parabola lens and fixed to the lower portion of a head slider(6). A parabola surface portion(7b) is provided on the lower outer circumference of the parabola lens to reflect all beams incident onto the parabola lens. A focus-keeping plane portion(7c) is formed in the center of the parabola surface portion. The parabola surface portion has a reflecting coating and the focus-keeping plane portions have an opening on a side.
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