| 摘要 |
The apparatus comprises a blocking/shielding means for changing the extent to which the earth's magnetic filed is experienced at a region. A power generator at the region generates power in response to the changing magnetic field at the region. In some embodiments, the blocking/shielding means is arranged to reverse the magnetic filed experienced at the region. Additional embodiments not involving the earth's magnetic field are disclosed in respect of charging laptop computers via a capacitive load and include piezo-electric keys, piezo-electric layer under keyboard, key drive magnet and coil or key driven pneumatic system. The piezo-electric system can also act as pressure transducers to monitor computer access or manners of use e.g. warning of repetitive strain injury. |
