Abstract: A magnetic restoring device of actuator provides a sufficient magnetic restoring force for stably holding a movable part of actuator in a neutral position. The actuator acts as an objective lens driving device in an optical pickup. A non-contact magnetic restoring mechanism is provided for causing pickup to return to a neutral position after a focusing or tracking operation. The magnetic restoring device comprises magnets, two magnetic inductive members, and two yokes wherein magnets and yokes are opposite; one arc-shaped surface is formed on the magnet in the focusing direction; and the other one is formed on the magnet in the tracking direction. The magnetic inductive members are provided between the magnets and the yokes to form a magnetic circuit, thereby increasing a magnetic field intensity and sensitivity of actuator. The device increases a magnetic restoring force in the focusing and tracking directions respectively.

Abstract: An objective lens holding apparatus includes an upper supporting portion and a bottom supporting portion not parallel with each other. The upper supporting portion and the bottom supporting portion have respectively one end connecting to an objective lens holder and another end connecting to a supporting arm anchor dock. The objective lens is mounted to the objective lens holder and is prevented from incurring an inclined angle while the objective lens is yawing. The elastic supporting arm anchor dock can keep the high resonant frequency within a desired range to enhance the stability of the optical pick-up head during reading and writing operations.

Abstract: A dual optical pick-up for accessing CD, CD-R and DVD discs is provided. The provided dual optical pick-up uses an objective lens and a laser source for DVD discs, and uses another objective lens and another laser source for CD and CD-R discs. Spirit of the invention is that both objective lenses are located in the same lenses holder, which connect to a guide rod, and the lenses hold moves only along a radius of the corresponding disc. Moreover, the laser beam produced by any laser source is transmitted through corresponding objective lens to a disc, and the reflected laser beam is transmitted through corresponding objective lens to a PDIC and then a spot is formed and detected. Hence, the location of each objective lens must satiate the requirement that any spot that corresponds to a specific track of disc does not mix with other spots that correspond to other track of disc.

Abstract: An apparatus with ring shape sleeve is provided. The apparatus is attached to a shaft and moves around the shaft, the varieties of the apparatus comprise objective lens holder of pick-up head. The characteristic of the invention is that apparatus and shaft are attached by ring shape sleeves where not only thickness of any ring shape sleeve is thin enough such that draft angle effect is negligible but also ring shape sleeve can be inlayed in the apparatus or be molded integrally with the apparatus. Therefore, not only shaft and apparatus are rigorously attached but also the space between shaft and apparatus is significant decreased. Thus, dynamic behavior of the apparatus is more controllable and yield of the apparatus is improved.

Abstract: A magnetic coil actuator which can provide a higher output but maintains the original volume and the same power consumption is disclosed. The coil actuator uses a movable magnetic coil which is adjusted of its shape to meet the magnetic field of a static magnet. The coil is suitably bent to have its two diametric sections falling into the magnetic lines of the magnet, so as to maximize the usage rate of the coil to the magnetic field. Therefore, the coil actuator provides a higher output applicable to a tracking or focusing device of a pickup head, and meets the requirements of high speed optical recording devices.

Abstract: The present invention provides a tilt angle adjusting mechanism for adjusting the tilt angle of the optical axis of a pickup head relative to the optical disc. The pickup head is furnished with an elongated hole, a slot or an L-shape base, several pre-loaded pressing elements and adjusting elements for a three-point mounting on two guide rods. The adjusting elements make the optical pickup head rotatably on two axes so as to adjust the tilt angle. An adaptive mechanism can also be incorporated for adjusting the tilt angle of the pickup head without modifying the original structure of an optical disc driver.

Abstract: A dual optical pick-up head for accessing CD, CD-R and DVD discs is provided. The provided dual optical pick-up head uses an objective lens and a laser source for DVD discs, and uses another objective lens and another laser source for CD and CD-R discs. Spirit of the invention is that both objective lenses are located in the same lenses holder which connect to a guide rod, and the lenses hold moves only along a radius of the corresponding disc. Moreover, the laser beam produced by any laser source is transmitted through corresponding objective lens to a disc, and the reflected laser beam is transmitted through corresponding objective lens to a PDIC and then a spot is formed and detected. Hence, the location of each objective lens must satiate the requirement that any spot that corresponds to a specific track of disc does not mix with other spots that correspond to other track of disc.

Abstract: The present invention provides a tilt angle adjusting mechanism for adjusting the tilt angle of the optical axis of a pickup head relative to the optical disc. The tilt angle adjusting mechanism includes two guide rods supported by a fixed holder and an adjusting holder. The adjusting holder receives an adjusting element for adjusting the guide rod moving toward or away from the optical disc. By adjusting one or both adjusting elements to move the guide rods in different axes, the correct tilt angle can be attained.