Abstract: A multi-band antenna includes a substrate with a first surface and a second surface, a first antenna structure with a first antenna coupling segment, a second antenna structure with a second antenna coupling segment, a first grounding section, a coupling section, a via hole, and a second grounding section. Both of the first antenna structure and the second antenna structure are disposed on the first surface. The first grounding section is connected to the first antenna coupling segment. The coupling section is disposed on the second surface and projected onto the first surface to form a coupling region. Both of the first antenna coupling segment and the second antenna coupling segment at least partially overlap the coupling region. The via hole penetrates through the substrate and is connected between the coupling section and the second antenna coupling segment. The second grounding section is connected to the coupling section.

Abstract: A test system for testing electrostatic testers, is used to test at least one electrostatic tester each including a voltage test terminal and a connection test terminal. The test system includes at least one optical coupler circuit and a chip. Each optical coupler circuit is coupled the voltage test terminal and the connection test terminal of one corresponding electrostatic tester, and each optical coupler circuit converts voltages of the voltage test terminal and the connection test terminal respectively to a voltage test signal and a connection test signal. The chip is couple to the at least one optical coupler circuit, and receives the connection test signal and the voltage test signal produced by the at least one optical coupler circuit, and determines whether the corresponding electrostatic tester connected to each optical coupler circuit is worked normally according to the connection test signal and the voltage test signal.

Abstract: A test system for testing electrostatic testers, is used to test at least one electrostatic tester each including a voltage test terminal and a connection test terminal. The test system includes at least one optical coupler circuit and a chip. Each optical coupler circuit is coupled the voltage test terminal and the connection test terminal of one corresponding electrostatic tester, and each optical coupler circuit converts voltages of the voltage test terminal and the connection test terminal respectively to a voltage test signal and a connection test signal. The chip is couple to the at least one optical coupler circuit, and receives the connection test signal and the voltage test signal produced by the at least one optical coupler circuit, and determines whether the corresponding electrostatic tester connected to each optical coupler circuit is worked normally according to the connection test signal and the voltage test signal.

Abstract: A multimode filter in an optical storage device is used for filtering an error signal and outputting a frequency signal. The multimode filter comprises a CLV and CAV mode filter and a switch. The CLV mode filter is used for filtering the error signal and extracting a narrow bandwidth signal, whereas the CAV mode filter is used for filtering the error signal and extracting a wide bandwidth signal. The switch is used for selecting either the CLV mode filter or the CAV mode filter according to the recording mode of the optical storage device.

Abstract: An optimal power calibration (OPC) method calibrates writing power for an optical disc. The optical disc includes a power calibration area, with a plurality of counting units and test blocks. The OPC method includes generating a plurality of first power levels by using an indicated power, selecting a plurality of second power levels from the first power levels, recording test data onto test blocks with the second power levels, reading the test blocks, and generating data signals and first beta values. The method further includes generating estimated optimal power by a calculating algorithm, generating a plurality of third power levels by using the estimated optimal power, recording test data onto test blocks with the third power levels, reading the test blocks, and generating data signals and second beta values. Optimal power is calculated by using the estimated optimal power, the first beta values, and the second beta values.

Abstract: An optimal power calibration (OPC) method calibrates writing power for an optical disc. The optical disc includes a power calibration area, with a plurality of counting units and test blocks. The OPC method includes generating a plurality of first power levels by using an indicated power, selecting a plurality of second power levels from the first power levels, recording test data onto test blocks with the second power levels, reading the test blocks, and generating data signals and first beta values. The method further includes generating estimated optimal power by a calculating algorithm, generating a plurality of third power levels by using the estimated optimal power, recording test data onto test blocks with the third power levels, reading the test blocks, and generating data signals and second beta values. Optimal power is calculated by using the estimated optimal power, the first beta values, and the second beta values.

Abstract: A multimode filter in an optical storage device is used for filtering an error signal and outputting a frequency signal. The multimode filter comprises a CLV and CAV mode filter and a switch. The CLV mode filter is used for filtering the error signal and extracting a narrow bandwidth signal, whereas the CAV mode filter is used for filtering the error signal and extracting a wide bandwidth signal. The switch is used for selecting either the CLV mode filter or the CAV mode filter according to the recording mode of the optical storage device.