Limbus/pupil switching for wearable eye tracking under variable lighting conditions

ABSTRACT

We present a low-cost wearable eye tracker built from off-the-shelf components. Based on the open source openEyes project (the only other similar effort that we are aware of), our eye tracker operates in the visible spectrum and variable lighting conditions. The novelty of our approach rests in automatically switching between tracking the pupil/iris boundary in bright light to tracking the iris/sclera boundary (limbus) in dim light. Additional improvements include a semi-automatic procedure for calibrating the eye and scene cameras, as well as an automatic procedure for initializing the location of the pupil in the first image frame. The system is accurate to two degrees visual angle in both indoor and outdoor environments.

References

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Index Terms

• Applied computing

  • Law, social and behavioral sciences

    • Psychology

• Human-centered computing

  • Accessibility

  • Human computer interaction (HCI)

    • Empirical studies in HCI