Although these devices track the eyes only within certain limits (the so-called headbox), the freedom of movement is still sufficiently large for respondents to be relatively unrestricted (at least in terms of a normal range of movement while watching screen-based stimuli). Screen-based devices require respondents to sit in front of a monitor and interact with screen-based content. Screen-based eye trackers (which are also called desktop, stationary or remote).LetвЂ™s have a look at the key features of each: Screen-based eye trackers They are used across variety of fields and research areas, but how they are used and the data they provide as a result can differ. While there are many different eye trackers, there are two principal types: screen-based and glasses. The relative difference in location of the pupil center and corneal reflection allows for deduction of the gaze direction.Дў Types of Eye Tracking: Screen-Based Eye Tracking and Eye Tracking Glasses Additionally, as infrared light is not visible to humans it doesnвЂ™t cause any distraction while the eyes are being tracked.

Light from the visible spectrum is likely to generate uncontrolled specular reflection, while infrared light allows for a precise differentiation between the pupil and the iris вЂ“ while the light directly enters the pupil, it just вЂњbounces offвЂќ the iris. The relative distance between the two areas allows the calculation of the direction of the gaze. The center of the eye (pupil center) is tracked in relation to the position of the corneal reflection. Normal light sources (with ordinary cameras) arenвЂ™t able to provide as much contrast, meaning that an appropriate amount of accuracy is much harder to achieve without infrared light. This isВ the optical tracking of corneal reflections, known as pupil center corneal reflection (PCCR).ДЄn infrared light source (and thus detection method) is necessary as the accuracy of gaze direction measurement is dependent on a clear demarcation (and detection) of the pupil as well as the detection of corneal reflection. These reflections вЂ“ the vector between the cornea and the pupil вЂ“ are tracked by an infrared camera. Near-infrared light is directed towards the center of the eyes (pupil), causing detectable reflections in both the pupil and the cornea (the outer-most optical element of the eye). These measurements are carried out by an eye tracker, that records the position of the eyes and the movements they make. Eye tracking refers to the process of measuring where we look, also known as our point of gaze.

Pc head tracking and voice type