Tobii data in QTM

The Gaze vector data is displayed in the 3D view of the window as a vector, for example color and length can be modified on the 3D view settings page in Project options.

There are two different types of data available for the Tobii eye trackers in QTM.

  1. The eye tracker device data.

    • For Tobii Pro Glasses 2, the device data is stored as Eye tracking data in QTM, containing the measured pupil diameters.

    • For Tobii Pro Glasses 3, the device data is stored in QTM as analog data, containing all data channels retrieved from the eye tracker device.

  2. The gaze vector data.

Gaze vector data

The gaze vector is provided by the Tobii recorder and then transformed in QTM to global 3D coordinates through the pose of the associated rigid body. The gaze vector data can be viewed in a Data Info window as Gaze Vector data.

The gaze vector data includes:

  • Device
    The device is the name of the Gaze vector. (L) and (R) stands for left and right eye.

  • X Pos
    This is the X position (mm) for the origin of the Gaze vector in the Global coordinate system.

  • Y Pos
    This is the Y position (mm) for the origin of the Gaze vector in the Global coordinate system.

  • Z Pos
    This is the Z position (mm) for the origin of the Gaze vector in the Global coordinate system.

  • X Vec
    This is the X value of the Gaze vector in the Global coordinate system.

  • Y Vec
    This is the Y value of the Gaze vector in the Global coordinate system.

  • Z Vec
    This is the Z value of the Gaze vector in the Global coordinate system.

  • Frame Number
    This is the frame number of the Tobii data. Since the frame rate of the Tobii data is mostly lower than the marker data, it means that the Tobii data is updated less often than the marker data.

Eye Tracker data

Tobii Pro Glasses 2

The eye tracker data from Tobii Pro Glasses 2 devices can be viewed in a Data Info window as Eye Tracker data. The eye tracker data for Tobii Pro Glasses 2 includes:

  • Device
    The name of the Tobii eye tracker device under Input devices. The name for a single Tobii device is by default "Tobii". Additional Tobii devices are numbered with 2, 3, etc.

  • L Pupil D
    The diameter of the left pupil in mm.

  • R Pupil D
    The diameter of the right pupil in mm.

  • Frame Number
    Frame number of the Tobii data. Note that the Tobii frame number is not the same as the QTM frame number.

Tobii Pro Glasses 3

The eye tracker data from Tobii Pro Glasses 3 devices can be viewed in a Data Info window as Analog data. The eye tracker data for Tobii Pro Glasses 3 includes:

  • Channel
    Channel name indicating the type of data.

  • Value
    Value of the recorded data including the units.

  • Board Name
    Name of the Tobii Glasses 3 device (serial number of the Recorder unit).

  • Channel No
    Analog channel number.