以光學模擬檢驗視線追蹤方法精確度

視線追蹤系統因為能直接量測使用者感興趣的點，所以視線追蹤系統變得越來越受歡迎。在目前所發展出的視線追蹤系統中，鮮少有能夠適用於眼鏡配戴者的視線追蹤系統，但目前配戴眼鏡的比率已經日漸增高，解決眼鏡折射問題的視線追蹤方法變得越來越重要。在本篇論文中，我們建構一套有加入眼鏡模型的模擬系統來檢驗視線追蹤方法精確度。我們測試了基於亮點特徵的視線追蹤方法，透過LED 點光源經反射和折射後所產生的亮點和瞳孔輪廓經折射在攝影機中的影像座標位置，來推估出視線。在實驗中加入雜訊，並使用不同度數的眼鏡來觀察視線追蹤方法精確度變化。根據實驗數據的結果，我們發現視線精確度確實會因度數和雜訊增加而使誤差增大。實驗中所檢驗的視線追蹤方法因為受到鏡片影響使得估測結果十分不準確，因此驗證了視線追蹤方法必須要考慮鏡片折射才能讓眼鏡配戴者使用。

關鍵字

視線追蹤；幾何光學；非接觸式視線追蹤；角膜折射；角膜反射；亮點；瞳孔輪廓；眼鏡鏡片；眼鏡

並列摘要

Gaze tracking is becoming more and more popular because it can directly measure the point of interest of a user. At present, only a few regression-based gaze tracking methods can be used to track the fixation point of a user wearing eyeglasses. As the increasing of the prevalence of myopia, gaze tracking methods that can solve the refraction problem of the spectacle lenses are becoming more and more important. In this thesis, an optical simulation system is developed to study the influences of spectacle lens refraction in gaze tracking. We tested accuracy of a glint-feature-based (GFB) gaze tracking method which uses the corneal refractions of IR LEDs and the refracted pupil center to estimate the line of sight of a user. In the experiment, image noises are added and a spectacle lens with several diopter values is introduced to test robustness of the GFB method against the image noises and the spectacle lens refraction. Experimental results show that the gaze tracking errors are directly proportional to both the image noise level and the absolute value of the spectacle lens diopter. When the spectacle lens refraction is not properly treated, the gaze tracking results will become very inaccurate. Therefore, gaze tracking methods should take the spectacle lens refraction into account to improve gaze tracking accuracy for users wearing eyeglasses.

並列關鍵字

Gaze Tracking ； Geometrical Optics ； Non-Contact Gaze Tracking ； Cornea Refraction ； Cornea Reflection ； Glint ； Pupil Contour ； Spectacle Lens ； Eyeglasses