GC0308 Infrared Camera ($17)
This is one of the least expensive cameras available that works practically well for near-eye tracking. It can be attached to glasses, used in AR/VR displays, and is UVC (USB) plug-and-play. Though tracking accuracy is slightly lower than with more expensive cameras, it is usable for most interactive applications.
Pros
- Inexpensive
- Small form-factor
- UVC/USB Plug-and-play
Cons
- Red-eye effect affects accuracy
- One cable needed per camera
- Heat can be a problem if enclosed