double phototransistor from old mouse

Hello, I've been trying to make a printer out of computer junk using old cd drive tray mechanism for movement and old optical mouse to get the movement information. But turns out that the mouse always says: "Hey, you moved by 20 points!" But what I need is a precise and more importantly REAL TIME counter. So I decided to take a different approach and use dual optointerrupter out of a ball mouse.
After some research, I've learnt that those are in fact ir photodiodes and dual phototransisors with common cathode. (Or emmiter, if you wish so). I've connected an IR phototransistor to my Duino before, but I'm not sure about this special stuff. Do you guys think this is the way to do it?
If not, how should i do it? I don't wanna destroy my phototransistor. :~

dualpthookup.png

Nevermind, solved it. Seems like this one was actually common collector type. Weird.