Requirements for the eyetracker to work properly

Below is a checklist for you to use if the eye tracker stops functioning in any of the following ways: 

  • The eye tracker seems to be turned off although everything else is running.
  • The eye tracker seems to be turned on, but it suddenly stops working during calibration or the test.
  • All icons are green, yet the eye tracker does not seem to pick up eye movement from the pupil in front of it.

An eye tracker has a lifetime of approximately 10 years. It's therefore rare that these devices break or stop functioning. In most cases, what has caused the eye tracker to malfunction can be traced to the other hardware or the software. 

Are all devices connected properly?

  • It's important that the eye tracker is mounted in the center, on the bottom of the external monitor.
  • Both your laptop and external monitor need to be plugged into the wall for the main power supply.
  • The external monitor is connected to the laptop with either an HDMI, VGA or USB cable. 
  • The eye tracker is connected to the laptop with a USB cable.

Is there enough power provided?

  • The eye tracker and its software require a lot of power. Make sure the eye tracker is connected to the laptop with a USB cable.
  • Make sure both the laptop and the external monitor are connected to the wall with the power cable.
  • If the laptop has more than one USB port, try switching the eye tracker to a different port.
  • Connect the eye tracker to a powered USB hub, which is then connected to the laptop.
  • How old is the Laptop/PC?
    • It is possible that although the PC is connected to the power outlet in the wall, it may be old and unable to transfer enough power to the eye tracker via the USB port. Try a different and preferably newer laptop/PC.

Is the software downloaded?

  • Are you running on the latest version of the Lexplore Testing Application?
    Check the number in the bottom left corner of your Testing Application and make sure it matches the number on the latest release. You can find that number here:
    Look below the Title of the page (example picture below):

  • The Tobii Service Software is usually downloaded when you initially set up everything and prepare for testing the first time. Any newly available update of the Tobii Software Service is communicated by Lexplore. If you are experiencing a problem, try updating the service by downloading it again. 

To download the Tobii Service Software, you need administrative rights on your laptop, so you will need to involve IT personnel in order to proceed.

🔁If you update either the Testing Application or the Tobii Service Software, make sure to reboot the Testing Application as well as the laptop/PC.

If you have Tobii 4C eyetracker please contact for help with software distribution.

How are the surroundings?

  • Detecting eye movements is a sensitive procedure. It is important that the lighting in the room is not too heavy or strong. For instance, if the external monitor is in front of a window and it is very sunny outside, this can impact the eye tracker. It is possible that the rays of light coming through the window are preventing the eye tracker from detecting eye movements. The same thing may occur with heavy lighting in the room.
  • Is the pupil sitting comfortably in their chair?  Perhaps all icons in the Testing Application have been checked and they are all marked green. The calibration with the pupil went well and you begin the test. Suddenly, it appears that eye movements are no longer being detected, and/or perhaps the post-assessment results inform you of this same thing. It is highly likely that the pupil moved a lot during the test, or significantly changed position after the calibration.

Ultimately, a BIOS update on the laptop is recommended to boost the power supply. For that, you will probably need to contact your internal IT helpdesk.


If all of the above have been checked and you are still experiencing a problem, please contact your local Lexplore Support for further assistance.

🛎️Here at Lexplore, we love to help our users with their questions and provide self-help guides for quicker service. Please vote below in the Question whether or not this article was helpful. 😊