Eyetracking is a technology to measure gaze and track eye movement. Sensors can be used to detect a person's eyes, calculate their gaze and track the eyes' movement. Studying a person's eye movement makes it possible to assess their alertness, attentiveness and focus, and thereby gauge the person's awareness and mental state.
Most eyetracking solutions in the market are based on the same principle whereby the eyes are illuminated with infrared light and cameras are used to register the reflection in the eyes. The reflections are analysed by image processing, with algorithms being applied to calculate the eye's position and the direction of gaze. Eyetracking can also be used to register biometrical data about the eyes, and also to gauge the head's position.
An eyetracking system often uses eyetracking together with an ordinary computer and screen, whereby eyetracking is either integrated in the screen, or is a free-standing element connected to the screen. More advanced eyetracking systems use several cameras for eyetracking of more than one person in a larger environment, such as an aircraft simulator. There are also examples of portable eyetracking whereby the technique is integrated with a forward-looking camera.
Today, eyetracking is an established technology used in a number of areas such as communication, computer interaction, behaviour analysis, market surveys and identification, and in vehicles and other specialist applications. Eyetracking can be used for several purposes:
- Analysing and understanding human behaviour and interaction with the surrounding world. By registering a person's gaze it is possible to analyse how the person perceives a situation, such as a digital interface, a film, an image or a physical situation such as a driving environment. Analysis of the pattern of a person's gaze provides important information about the situation and can e.g. form the basis for scientific analyses, interface design, advertising messages, or the design of a driving environment.
- Enabling interaction between man and machine. When a machine knows where a person is looking, this allows for expanded functionality and increased safety. Examples of where eyetracking can create increased functionality can be found within medical technology, where a surgeon whose hands are otherwise engaged can control functions with his or her gaze. Another area is within the automotive industry, where the vehicle can read off whether the driver is attentive or sleepy, and take action on this basis. Eyetracking is a key component of the development towards autonomous cars.
- Hands-free computer interaction A person’s gaze can replace a mouse or other input devices when using a computer, which increases opportunities for people who are unable to use their hands to interact with a computer. Eyetracking also makes it possible to create more effective user interfaces and better user experiences by combining gaze with traditional input methods such as a keyboard and mouse.