Quantity   Component name
1 × This Aliexpress Mouse for teardown - https://www.aliexpress.us/item/3256804999294357.html
1 × OR: A https://www.yspringtech.com/article/YS8205/ sensor, if you can find it
1 × Waveshare RP2040-Zero
1 × Red or IR LED
1 × Optional: 3mm biconvex laser focusing lens (Alternatively: cut down the lens the mouse came with)