dc42:
Please explain the voltage requirements for the lense. Have you a specification or datasheet for the lense?The +9V is where you connect the incoming power. You need to provide 9V or a little more at 250mA. You can use the same supply to power the Arduino if the supply can handle the extra current for the Arduino + anything running from its 5V supply.
The lens operates between 2-3kV, but we aim to be able to control it with a system.
Can the roles of the resistors prior to the op-amp and the role of the op-amp be explained in more detailed?
The resistors coming off the HVM i am assuming is to make safe the connection back to arduino ground?
(sorry im quite a beginner trying to attempt a complex project)