廣角多層光學鍍膜擴增實境光波導眼鏡

Abstract

本文介紹了一個新概念-擴增實境領域中的多層光學鍍膜光波導。實際上，隨著數十年來的蓬勃發展，擴增實境已經建立了與眾不同的功能，使其在各個領域中得到廣泛應用。將虛擬圖像疊加到外部現實世界的視野上，擴增實境促進了諸多領域的應用，例如教育，醫療手術，工程，娛樂，圖像導航，甚至軍事應用。然而，AR仍然存在兩個主要缺點：（1）擴增實境頭戴式顯示器設備的龐大笨重帶來的不便； （2）有限的視角。為了改善上述缺點，我們引入了多層光學鍍膜光波導，其厚度比擴增實境頭戴式顯示器的傳統設計要薄。我們將光波導分為兩部分：（1）基於non-pupil forming system的自由曲面准直儀，該系統由三個高階項extended polynomial表面構成，（2）波導後段直接接合了多層光學鍍膜耦合輸出反射層。傳統上，FOV的寬度取決於單一一個耦合輸出反射層的尺寸，因為單一一個表面決定了所有反射進入觀察者瞳孔的反射光。我們的多層塗層表面使光波的反射更加靈活。每個塗層都具有一個臨界角，該臨界角過濾並反射具有匹配之入射角的光波。換句話說，具有不同入射角的光波在相應的塗層表面處反射或穿透。因此，與傳統光波導眼鏡相比，我們通過光學鍍膜光波導眼鏡達到了40°的超廣角，其厚度也被壓縮到了3 mm。

This thesis studies a design methodology- a multiple coating surface waveguide in the field of augmented reality (AR). In fact, with its blooming developments over decades, AR has established distinguishing features that makes it widely applicable among various fields. Overlapping the virtual image onto the external view, AR has contributed to applications, such as education, medical surgery, engineering, entertainment, image-guided navigation and even military. However, there are still two major drawbacks for AR: (1) The inconvenience brought by the bulkiness of AR head mounted display (HMD) devices; (2) The limited magnitude of the field of view (FOV). To overcome the above drawbacks, we investigate a multiple coating surface waveguide that is thinner than the traditional designs of the AR HMD devices, We separate our waveguide into two parts: (1) The free-form surface collimator based on the non-pupil forming system, constructed by three high order term extended polynomial surfaces, (2) The multiple coating surface directly attached after the waveguide. Traditionally, the width of FOV relies on the size of the single couple out surface as the single surface determines all wave reflections. Our multiple coating surface allows more flexibility on the reflections of optical waves. Each coating possess a critical angle that filters and reflects the optical waves that have a matching incident angle. In other words, the optical waves with different incident angles are reflected at corresponding coating surfaces. Thus, we have achieved a large FOV with a waveguide, which thickness is estimated to be 3 mm, when compared to the traditional waveguide.