Generate Eye diagram for system response

I am able to generate the response of a system (laser) in what is called the oscilloscope mode. I wanted to know if there is a nice way to generate an eye diagram of the same. Input: bit sequence [ on off off on...] output from my prog is the response of system (laser) to this bit sequence I would like to generate an eye diagram for the same instead. I am not using simulink to generate the response.

Exactly like how its is in this website

http://www.tek.com/support/faqs/it-possible-display-eye-pattern-my-oscilloscope

Thanks