Troubleshooting eye tracking difficulties

If you are using eye gaze and experiencing difficulty calibrating or making accurate selections there are a few things that you can try yourself before contacting our Support Team.

Environment and Positioning

Eye tracking all works through reflections of infrared (IR) light off of your eyes. As such, there are some environmental and positioning factors that might impact tracking performance:

Bright light sources – the sun, spotlighting, and even windows can all add extra reflections, sometimes only when the eyes are looking in a certain direction.

Try moving into shade, dimming or turning off lights, and closing curtains and blinds to minimise reflections.
If these changes help, you could consider keeping things this way, or moving to another location with fewer external light sources.

Most older trackers are not designed to cope with usage outdoors due to the levels of IR coming from the sun. Recent improvements in technology have made outdoor usage more accessible.

Poor positioning – eye tracking all relies on the tracker being able to see your eyes clearly, if you are too close, too far, or at an unusual angle relative to the device it may struggle to detect you.

• Most eye trackers work best at around 55-60 cm (22-24 inches) – an arm’s length is usually a good approximate for this. Grid’s positioning guide changes colour to give an indication of whether you’re at a good distance or might need to move – where possible, always move the device, not the user.
• The top edge of the device should be in line with your eyes, with the screen angle perpendicular to the gaze direction. If the device is too low, your eyes may be partially covered by your eyelids. Moving the device higher can help to make your eyes clearer.

Using Grid’s settings to improve eye gaze access

You can make use of the features in Grid’s settings to get the best chance of success with eye gaze. These settings are accessed from Grid’s Menu – Settings – Access – Eye gaze.

• Calibrating within settings will give feedback after completion. Ideally you should aim for most points to be green for the best accuracy. Some trackers support improving specific points by directly selecting them.
• As a general rule, more calibration points will give better accuracy – a 9 point calibration is more likely to give accurate access than a 5 point calibration.
  
• If your tracker supports showing a video feed, this can be a useful tool to see what the camera sees.
  Look out for additional reflections or glare on the eyes or glasses if they’re worn. If the video feed isn’t supported, sometimes using the device webcam can give a good approximation.
  
• If accuracy is challenging only in certain areas of the screen, ask the user to look in those tricky areas whilst you monitor Grid’s positioning guide. Look out for eyes flickering or tracking being lost completely. You may need to move the device or change location to reduce the impact.