Yes this was my first choice,but with optical isolation
how will it work ?

You apply the input signal to the relay coil - when the signal is "ON", the relay opreates; when the signal is "OFF", the relay releases.
Obviously, you need to choose the coil rating to suit the input signal.

It should also be obvious that the input signal is completely isolated from the microcontroller - there is no need for an opto isolator! (unless you have some special requirement for a double isolation barrier...?)