Remote control and power system
A remote device such as a control value ( 4 ) is powered and controlled by optical energy, supplied by an intensity-modulated light source ( 8 ) and optical fiber ( 10 ). After conversion into electrical form, the light is detected at ( 12 ) and applied to a piezoelectric transformer ( 14 ). The output of the transformer powers and control an actuator ( 16 ) of the control value.
1. A system for controlling and providing electrical power to an electrical device at a remote point comprising: a light source operable to produce an intensity modulated optical signal in response to a control signal, an optical fibre for guiding said optical signal to a photodetector located at said remote point, said photodetector being operable to produce an electrical signal in response to said optical signal and a piezoelectric transformer connected to said photodetector for convening said electrical signal into a higher voltage second electrical signal for controlling and providing power to the electrical device.
2. A system according to claim 1 in which the electrical device comprises a piezoelectric mechanical actuator.
3. A system according to claim 1 in which the electrical device comprises a micro-machined electrical system.
4. A system according to claim 1 in which the electrical device comprises a gallium nitride semiconductor device.
5. A system according to any preceding claim in which the light source comprises a solid state laser.
6. A system according to claim 5 in which the optical signal is produced by directly modulating, the laser using the control signal.
7. A system according to claim 5 in which the laser is operable to produce a continuous optical output and further comprising optical modulation means operable to modulate said continuous optical output in response to said control signal.