The new generation of speech generating devices offers several improvements based on customer feedback and technological advances that build on the success of its C-Series. Tobii Technology, which has led the charge for eye tracking and gaze interaction technology for individuals that are nonverbal and with limited ability to physically interact, announced that its new Tobii I-Series is now available.
Opening up the world of communication for a nonverbal child or adult can be a challenge, but today, technology continues to amaze. Eye tracking is also used to create actions, such as the ones used to operate a wheelchair without the use of limbs. The technology provides a voice to people that previously had little way to express his or her thoughts.
You can search our database of over 9000 EyeLink publications and see how people in your field are using eye-tracking data.Tobii I-Series Eye Tracking Communication Device Opens World of Communication for Non-Verbal IndividualsĮye tracking, a fairly new technology, makes use of the iris to give commands to a computer system that in turn speaks for the user. If you’d like to learn more about eye tracking and how it could help your research, check our Eye Tracking Solutions page and blog posts. In “Pupil-CR” tracking, the change in CR position is essentially “subtracted” from the change in Pupil position, thus making it possible to disambiguate movements in the pupil center on the camera sensor that are the result of genuine rotations of the eye, from movements of the pupil center on the camera sensor that are the result of shifts in head position. Modern video-based eye trackers exploit this difference in the Pupil-CR relationship in order to compensate for head movements. So how do eye trackers distinguish between changes in pupil position on the camera sensor that result from rotations of the eye from those that result from movements of the head? Critically, with head movements the relationship between the center of the pupil and the center of the corneal reflection remains the same, whereas when the eye rotates, the relationship changes. Why the Corneal Reflection is so ImportantĪs you can see, in this case, both the pupil *and* the corneal reflection move on the camera sensor. The corneal reflection is simply the reflection of a fixed light source (the infrared illuminator) that sits next to the camera, as illustrated below.
So how is this done? The eye-tracking software uses image processing algorithms to identify two key locations on each of the images sent by the eye-tracking camera – the center of the pupil, and the center of the corneal reflection. Within 3 ms from the image of the eye being taken, EyeLink systems work out where on the screen the participant is looking, and relay this information back to the computer controlling stimulus presentation.
Both the EyeLink 1000 Plus and EyeLink Portable Duouse single cameras that are capable of taking up to 2000 images of both eyes every second.
So how do video-based eye trackers actually work?Īt the heart of all video-based eye tracking is a camera (or cameras) that takes a series of images of the eye. All SR Research EyeLink systems employ video-based eye-tracking, as do most other commercially available eye trackers. One of the biggest technological changes over the last couple of decades has been the near-universal adoption of video-based eye tracking as the technique of choice.