optical sensors from projection TV

I have a *lot* of junk from old TVs -  projection lenses, a fresnel lens and pcbs.
so far I've only used caps and resistors in small projects.

recently I came across a set of 4 optical sensors anchored to the inside of a projection TV, I believe they are used for auto alignment of the RGB images on the mirror.

What is a good project to use these in? could I use them to possibly build some sort of solar tracker ? perhaps using an arduino ?

any ideas appreciated.