摘要:
An optical pickup device and a focusing control method thereof are provided which can determine a DC offset caused by cross-talk of a focus error signal, eliminate the DC offset based on the determination, correct errors in a focus error signal of a main beam, which is caused by interference of side beams, so that optimal focus tracking can be performed. For this, the optical pickup device has at least one or more light sources, a diffraction optical element which diffracts light from the light source into a plurality of beams, an objective lens which condenses the plurality of beams diffracted by the diffraction optical element, a photo detector which detects the plurality of beams reflected from discs, and an auxiliary photo detector which detects the plurality of beams reflected from the discs to perform error correction of focus error detection signals obtained by the photo detector.
摘要:
An optical pickup apparatus according to an embodiment of the present invention, comprises an optical unit for projecting a plurality of wavelengths of light, the light including a celadon light, toward a recording medium and receiving the light reflected from the recording medium to thereby detect an information signal and an error signal, and a compatible objective lens for focusing a light projected from the optical unit to thereby form an optical spot on a recording surface of the recording medium and applying at least three light having different wavelength ranges to be compatibly used for both the high-density and the low-density recording mediums. Accordingly, the optical pickup apparatus is capable of compatibly employing a high-density recording medium, which uses a celadon light and is slimmer than a digital versatile disc (DVD), and at least one low-density recording medium.
摘要:
An optical pickup apparatus according to an embodiment of the present invention, comprises an optical unit for projecting a plurality of wavelengths of light, the light including a celadon light, toward a recording medium and receiving the light reflected from the recording medium to thereby detect an information signal and an error signal, and a compatible objective lens for focusing a light projected from the optical unit to thereby form an optical spot on a recording surface of the recording medium and applying at least three light having different wavelength ranges to be compatibly used for both the high-density and the low-density recording mediums. Accordingly, the optical pickup apparatus is capable of compatibly employing a high-density recording medium, which uses a celadon light and is slimmer than a digital versatile disc (DVD), and at least one low-density recording medium.
摘要:
A memory module, a memory unit, and a hub with a non-periodic clock and methods for using the same. An example memory module may include a phased locked loop, receiving an external, periodic clock and generating one or more internal periodic clocks and a plurality of memory units, receiving one of the internal periodic clocks or a non-periodic clock from an external source.
摘要:
A semiconductor memory module and a semiconductor memory device are disclosed. In one embodiment, the invention provides a semiconductor memory module comprising a circuit board, a plurality of semiconductor memory devices adapted to operate during a test mode and a normal operation mode and mounted on the circuit board, a first signal line set comprising a plurality of first signal lines connected to the plurality of semiconductor memory devices, and a plurality of second signal line sets. Each semiconductor memory device comprises first terminals adapted to receive first signals from the first signal lines, second terminals connected to a corresponding one of the second signal line sets, a third terminal adapted to receive an enable signal during the test mode, and a signal transmitting unit adapted to output second signals to the second terminals in response to the enable signal.
摘要:
A memory module includes a first memory group including a plurality of memory devices, a second memory group including a less number of memory devices with respect to the memory devices in the first memory group, a register configured to provide a command/address signal to the first memory group and a delayed command/address signal to the second memory group, a first signal line configured to transfer the command/address signal to the first memory group, and a second signal line configured to transfer the delayed command/address signal to the second memory group.
摘要:
A memory module includes a first memory group including a plurality of memory devices, a second memory group including a less number of memory devices with respect to the memory devices in the first memory group, a register configured to provide a command/address signal to the first memory group and a delayed command/address signal to the second memory group, a first signal line configured to transfer the command/address signal to the first memory group, and a second signal line configured to transfer the delayed command/address signal to the second memory group.
摘要:
An optical pickup actuator and a method of assembling the same is provided. The method of assembling the optical pickup actuator comprises the steps of providing a blade having at least one objective lens mounting area and an aberration correcting mechanism mounting area, arranging an objective lens in the objective lens mounting area, positioning an aberration correcting mechanism in the aberration correcting mechanism mounting area such that the central point of the aberration correcting mechanism coincides with the central point of the objective lens, tuning the aberration correction mechanism, and adhering the aberration correcting mechanism using an adhesive.
摘要:
A memory module and related method are disclosed. The memory module comprises a clock generator configured to generate first and second internal clock signals in relation to an external clock signal, and a register configured to receive the first and second internal clock signals. The register stores an external control/address signal in response to the first internal clock signal and transmits an internal control/address signal derived from the external control/address in response to the second internal control/address signal.
摘要:
An optical pickup actuator and a method of assembling the same is provided. The method of assembling the optical pickup actuator comprises the steps of providing a blade having at least one objective lens mounting area and an aberration correcting mechanism mounting area, arranging an objective lens in the objective lens mounting area, positioning an aberration correcting mechanism in the aberration correcting mechanism mounting area such that the central point of the aberration correcting mechanism coincides with the central point of the objective lens, tuning the aberration correction mechanism, and adhering the aberration correcting mechanism using an adhesive.