虛擬實境是一項在教育、娛樂、訓練、軍事以及醫療領域逐漸被廣為應用的技術，近年來在虛擬實境的環境之下互動績效更是一個蓬勃發展的議題，早期與虛擬環境互動的方式大多是以2D的輸入設備去操作3D的場景，但是往往會造成3D空間操作上的效率問題，因此體感控制器、追蹤筆、動作擷取設備、3D滑鼠等3D輸入設備逐漸被發展出來，而其中又以指向姿勢為互動媒介進行遠端操作最為常見，然而在互動操作過程常常會有3D空間感知不良、手部的振顫、疲勞以及精確度方面的問題。綜合以上問題本研究旨為探討凝視(Gaze-directed)與非凝視(Hand-directed)兩種手部指向方式，對於不同立體視覺下的操作績效與使用者知覺之影響，以發展出在虛擬環境下之最佳績效的手部指向方式。其結果將做為未來立體虛擬環境下人電腦互動設計參考之用。
本研究可分為兩部分，分別探討在靜態物件點擊以及動態物件追蹤，結果顯示非凝視指向方式有較佳的整體績效且對於使用者的生理負荷較少，但是在動態追蹤任務中凝視指向方式則有助使用者進行深度軸上之微調瞄準降低失誤次數。而在立體視覺調整中，負視差(Negative parallax)的配置給予使用者較佳的深度知覺與似真實世界的距離感。此外本研究發現受測者在涉及深度軸上之移動較不精確且緩慢。再者根據視覺疲勞與工作心智負荷可得知本實驗條件設置沒有顯著的影響兩者的變化。本實驗結果可提供給開發者一項虛擬環境互動設計準則，以謀求更為人性化之發展。

Virtual reality has been applied into many fields, such as education, entertainment, medical, and military. However, since past applications focused on manipulation of 3D displays by 2D devices, they had problems of inaccuracy and inefficiency. Therefore, several 3D input devices have been developed, such as Kinect, Stylus, Motion capture, and 3D mouse. However, while participants are in virtual environments, there have been many interaction problems, including hand tremors, visual and body fatigues, and inaccuracies. This research aimed to explore the participants’ performances with negative and positive parallax by using gaze-directed and hand-directed pointing methods through Kinect.
There were two experiments in this research, including static and dynamic tasks. The result showed that the participants had better overall efficiency and less physiological loading using hand-directed pointing method. However, they had better depth perception and targeted with less errors using gaze-directed pointing method in tracking tasks. Furthermore, targets with negative but not positive parallax were more realistic and could provide participants with better depth perception. This research also showed that participants could track targets quickly and accurately in the frontal plane. This research contributes to provide a guideline for future researchers to explore issues of human interaction within stereoscopic environments.

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