Low voltage communication between subsystems in a laser eye surgery system
A laser eye surgery system comprises subsystems which communicate with one another through low voltage differential signaling (LVDS). The laser eye surgery system may comprise a first subsystem interface, including an LVDS driver or transmitter coupled to and in communication with an LVDS receiver of a first subsystem of the laser eye surgery system. The first laser eye surgery subsystem itself may comprise an LVDS transmitter coupled to and in communication with an LVDS receiver to return data to the first subsystem. Further laser eye surgery subsystems may also include the same arrangement of drivers and receivers with respective subsystem interfaces. LVDS lowers power consumption and the risk of error in communication between laser eye surgery systems, leading to safer and more reliable surgical procedures performed.
1. A laser eye surgery system, comprising:
a first subsystem;
a processor; and
a first subsystem interface connected to the processor and connected to the first subsystem and configured for providing bidirectional communication with the first subsystem, the first subsystem interface including:
a first subsystem interface differential transmitter for transmitting a first differential signal to the first subsystem for controlling the first subsystem, and
a first subsystem interface differential receiver for receiving data from the first subsystem via a second differential signal separate from the first differential signal;
wherein the first subsystem comprises first subsystem control electronics in communication with the first subsystem interface, wherein the first subsystem control electronics includes:
a first subsystem differential receiver, separate from the first subsystem interface differential receiver, the first subsystem differential receiver having a load and being in communication with the first subsystem interface differential transmitter to receive from the first subsystem interface differential transmitter the first differential signal for controlling the first subsystem, and
a first subsystem differential transmitter, separate from the first subsystem interface differential receiver, the first subsystem differential transmitter being in communication with the first subsystem interface differential receiver for transmitting the data to the first subsystem interface differential receiver via the second differential signal.
2. The laser eye surgery system of claim 1 , further comprising:
a second subsystem; and
a second subsystem interface connected to the processor and connected to the second subsystem, the second subsystem interface including:
a second subsystem interface differential transmitter for transmitting a third differential signal from the processor to the second subsystem for controlling the second subsystem, and
a second subsystem interface differential receiver for receiving second data from the second subsystem via a fourth differential signal;
wherein the second subsystem comprises second subsystem control electronics in communication with the second subsystem interface, wherein the second subsystem control electronics includes:
a second subsystem differential receiver having a load and being in communication with the second subsystem interface differential transmitter to receive from the second subsystem interface differential transmitter the third differential signal for controlling the second subsystem, and
a second subsystem differential transmitter for transmitting the second data to the second subsystem interface differential receiver via the fourth differential signal.
3. The laser eye surgery system of claim 1 , wherein the first subsystem comprises a vacuum subsystem, a ranging subsystem, a laser subsystem, a laser interface subsystem, a power distribution subsystem, a patient interface subsystem, or an XY-scanning subsystem.
4. The laser eye surgery system of claim 3 , wherein the ranging subsystem comprises an OCT imaging device.
5. The laser eye surgery system of claim 3 , further comprising a plurality of subsystems.
6. The laser eye surgery system of claim 5 , wherein each subsystem of the plurality of subsystems, except for the power distribution subsystem, communicates with at least one other subsystem through differential signaling having a power consumption at each load of 1.2 mW.
7. The laser eye surgery system of claim 5 , wherein the plurality of subsystems comprises a vacuum subsystem, a ranging subsystem, a laser subsystem, a laser interface subsystem, a patient interface subsystem, and an XY-scanning subsystem, and wherein each subsystem of the plurality of subsystems communicates with at least one other subsystem using differential signaling having a power consumption at each load of 1.2 mW.
8. The laser eye surgery system of claim 1 , wherein the first subsystem interface differential transmitter includes a current source configured to supply a constant current onto a differential pair.
9. The laser eye surgery of claim 8 , where the current source is configured to supply the constant current of 3.5 mA.
10. The laser eye surgery system of claim 1 , wherein the first subsystem interface differential receiver has a pair of differential input terminals, the first subsystem interface differential receiver further comprising a resistor connected across the pair of differential input terminals.
11. The laser eye surgery of claim 10 , where the resistor has a resistance of 100 Ω.