Measuring Screen_Phys_Coords; Figure 8-4: Measuring Screen_Phys_Cords - SR Research EyeLink 1000 Installation Manual

screen_pixel_coords = 0.0, 0.0, 1024.0, 768.0
screen_distance – specifies the distance to the top and bottom of the display surface from the
participant's eye, respectively. This setting is not applicable to EyeLink remote tracker. The
default values read as following:
screen_distance = 600 660

8.4.1 Measuring screen_phys_coords

All screen physical coordinate measurements are in millimeters. It is recommended that a
straight ruler be used.
If your screen is centered in front of the subject, a quick method for obtaining the
measurements below is to measure the screen width in mm and the screen height in mm, and
then to divide each of these by two to yield the distances S1, S3 (width/2) and S2/S4
(height/2).
The new settings for the screen_phys_coords in the PHYSICAL.INI file are determined by:
screen_phys_coords = -S1, S2, S3, -S4
In the screen_phys_coords, measure the distance from the center of the dot to the end of the
active part of the monitor screen. Start on the left side (S1) and follow round to the top (S2),
right (S3) and bottom (S4). This is illustrated in Figure 8-4.

Figure 8-4: Measuring screen_phys_cords

Testing the Host PC Installation 69
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