Abstract: In optical pickup apparatus, a laser beam generated from the laser source is reflected from a beam splitting means via an objective lens toward an optical disc. The beam reflected from the disc is received so that information is reproduced. An objective lens positioning system is located around the objective lens, and has rack gears, pinion gears, and a fixed supporting part having a guide rail formed thereon. A motor driving part detects a thickness of the disc to move the objective lens positioning system when the disc is changed in thickness.

Abstract: An integrated optical pickup system for reading information signals recorded on a recording surface of a selected optical disk, which is selected from both optical disks so as to be loaded on a disk tray, is comprised of a first glass substrate equipped with means for generating a first and a second focused light beams, letting one of the focused light beams impinge onto the recording surface of the selected optical disk and collimating the focused light beam reflected from the selected optical disk, wherein each of the focused light beams is focused onto the recording surface of a corresponding optical disk, respectively; and a second glass substrate, integrated therein with a detector capable of measuring the intensity of a light beam detected and a reflection layer, for reflecting a portion of the collimated light beam to the detecting lens, thereby allowing the integrated optical pickup system to read the information signals off the recording surface of the selected optical disk.

Abstract: An optical imaging system having a simple optical shading filter for reducing various aberrations is disclosed. The optical imaging system includes one or more lenses, a stop installed between the lenses, and an optical shading filter for reducing the extra axial aberrations. The optical shading filter is an gradual optical shading filter having a transmittance which deceases cuing toward the peripheral portions. The optical imaging system is simple in its structure, and is effective in its function. Further, the manufacturing is easy, and the manufacturing cost is low.

Abstract: An inventive method for producing an optical tape comprises the steps of sequentially depositing a label layer and a reflection layer on a substrate. The label layer and the reflection layer has a same reflexibility in a predetermined wavelength range of a laser beam, thereby providing a label image to a user as well as capability of information recording.