Tobii X2-30, Руководство пользователя

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Studio and include either five or nine points. The calibration points can be drawn on a paper, marked on a cali-
bration board, or marked on objects in the scene. Make sure that the corners of the calibration grid are exactly
90 degrees and that the center point is exactly in the middle of the grid. It is also good to include the 25% larger
Active Display Area around the grid to make it easier to measure the parameters required in the X Configuration
Tool.
How to calculate the 25% larger Active Display Area for the setups that use an external calibration grid is de-
scribed below:
– Active Display Area Height = 1.25 × Calibration grid height.
– Active Display Area Width = 1.25 × Calibration grid width.
• A A — eye tracker angle. Calibrate the digital angle gauge supplied with the Tobii X2 Eye Tracker desk stand package
before measuring the angle between the eye tracker and the vertical plane. To calibrate the digital angle meter, place
it on a flat, vertical surface and press the
“ Zero ” button. To measure the angle, place the digital angle gauge on the
front surface of the eye tracker. In many setups the angle is commonly around 25 degrees.
• B B — display angle. Measure the angle between the vertical plane and the active display using the digital angle meter.
In a scene camera setup measure the angle between the vertical plane and the calibration grid. If the display is tilted
forward you should enter a negative angle (use
“ - ” in front of the value). If the active display is completely vertical the
angle value is 0. In a scene camera setup where you want to track objects on a horizontal table the angle would be
90 degrees.
• C C — Height difference between lowest row of pixels on the display and the measuring point of the eye tracker (read
5.1 Reference Measurement Point of the Tobii X2 Eye Tracker, page 15). Measure the height difference between
the measuring point on the eye tracker and the bottom of the active display area. If the active display is located below
the measuring point on the eye tracker (for example, in a projector setup) the value will be negative. Enter the value
in the X Configuration Tool with a
“ - ” in front to signify it as a negative value.
• D D — distance between the measuring point of the eye tracker (read 5.1 Reference Measurement Point of the Tobii
X2 Eye Tracker, page 15) and the display. Measure the distance from the measuring point on the Tobii X2 Eye Track-
er to the front of the active display on the monitor, projection screen, or TV screen, or in a scene camera setup to the
virtual screen. If the measuring point on the eye tracker is located behind the active display, enter a negative distance
(use
“ - ” in front of the value).
Always make sure that the distance to the active display is long enough for the eye tracker to track the en-
tire area. Please read section
6 Positioning, page 19.
Tobii X2-30 Eye TrackerUser ’ s manual v.1.0.3 - en-US
5 The X Configuration Tool
17