u/CODEnight8

I took this part from an old mouse, it was located next to the mouse wheel, it is an encoder for the wheel to know when the wheel moves, in front of it there was an infrared led, this part in the pic is the receiver of the infrared led light i believe it is a dual photo-transistor but im not sure and ai couldn't help me at all, is there anyway that could help me to know what is it exactly and helps me to know what are the pins for

Excuse me for my bad English