Performance

• Measurement technique: Video. Pupil and dual first Purkinje image
• Guaranteed sampling frequency: 250Hz with no dropped frames
• Resolution: 0.05°
• Accuracy: 0.125° - 0.25°
• Horizontal range: ±40°
• Vertical range: ±20°
• Allowable head movement: ±10mm
• Measurement units: Fick, Helmholtz coordinates in degrees and screen position in mm
• CPU utilization: 25% for eye tracking with mimic and camera window (typical)
• Software triggers: Implemented as Callback to user routine when subject looks into Region of Interest (ROI)
• Number of ROIs: Over 100

Optics

• Infrared illumination wavelength: 930nm
• Camera type: 250Hz digital camera
• Connection to PC: firewire

Eyetracker
Interface Box

• The eyetracker interface box is located near to the camera and is powered from a universal mains adaptor
• It provides 6 front panel BNC connectors for user connections and direct connection to a data acquisition system:
• Analogue (or 1 bit digital) trigger input time marker for synchronisation connection from external apparatus
• Configurable analogue eyeposition x, y and pupil diameter, and trigger output (delayed version of trigger input)
• Digital tracked/not tracked signal for each frame, plus two status leds providing visual indication of the trigger input and tracking status (leds can be disabled)
• 3 bit digital market input to record precise stimulus timing information direct from the ViSaGe (or other visual stimulus generator)

All outputs synchronously run at a constant latency and can therefore be fed directly to a data aquisition system

Supplied Software

• In process COM server: Dual interface support late and early binding, with complete type library
• Toolbox demonstration programs: For Delphi, Visual Basic, C++Builder and MATLAB. Full source code provided
• videoEyetrace: Complete eye tracking environment, with mimic display and scrolling eye position graph. Includes visual stimuli for saccade and smooth pursuit experiments, plus bitmap images for reading and visual scanning experiments

Minimum System Requirements

• Processor: 3GHz Pentium 4 or AMD Athlon (the faster the better)
• Memory: 512MB RAM
• Hard disk drive 1GB
• Stimulus Display: ViSaGe visual stimulus generator or dual VGA display
• Free USB 1.1 or USB 2 socket
• Free Firewire socket (or spare slot for adaptor card). The EIB will automatically power the camera if the host firewire socket does not provide power.
• Motherboard: A free PCI slot is necessary if the optional visual stimulus generator is used. A free PCI slot is necessary if a firewire card is required.
• Windows: Windows XP