Daifs Corneal Visual Center (CVC) Localizer (Locator) is a point Light Source of Infra Red (IR) light, attached and fixed to any eximer laser machine, located at equal distance and in exactly opposite direction from the middle of a detecting camera that detects IR light reflection from the corneal surface and the pupillary margin of the iris with a point fixation target or its virtual extension, perpendicular to the plan containing the localizer and the middle point the inlet of the detecting camera, exactly in the middle of the distance between the localizing point light source and the middle point the detecting camera. With the Localizer in position and activated, the CVC will be seen on the screen of IR eye tracking as a white dot somewhere inside the white circle that represents the detected pupillary margin. The center of the pupil is automatically detected by the eye tracking software system and is marked on the screen by a cross which will considered by treatment software of the machine as the center of the refraction correction laser treatment. After accurate in-focus positioning of eye to be treated with the patient fixing the fixation target, the position of this cross could be manually changed to the position of the white dot representing the CVC and confirming by OK button. The relation between the CVC and the pupillary margin image is automatically fixed by the eye tracking system all over the whole laser treatment of this particular eye.
