用於中、遠距離之光學測距法

Optical Measurement Method for Middle- and Long-Distance Depths

蔡承樺(Cheng-Hua Tsai)

指導教授 ： 蔡睿哲

國立臺灣大學/電機資訊學院/光電工程學研究所/博士(2015年)

https://doi.org/10.6342/NTU.2015.10903

摘要

本論文期望能建立一個能夠辨識中、遠距離之光學測距法來獲得物體的相對深度資訊，論文中將會分別介紹目前各種不同量測深度資訊的方式並說明近、中、遠距離量測深度資訊方法的優點及需要改善的地方。在架構出中、遠距離之光學測距法的過程中，首先會先提出整個研究方法的概念及理想的實驗架構，並藉由波動光學的方式來推測及評估實驗的可行性。在實驗的進行前，所有將在實驗使用的光學元件的特性及尺寸大小，也將由模擬後的理想參數來決定並放置在成像系統中。

實驗架構主要是在待測物體的前方架設一組影像成像系統，隨後在影像的成像面上放置針孔，藉由針孔的結構觀測影像發散程度的不同及發散趨勢，來反推並獲取深度資訊。實驗中所使用的光學元件也一併會在論文中討論，包括待測物的選擇方式、照射光源的類型、CMOS (Complementary Metal Oxide Semiconductor)影像感測器的選擇、影像處理的方式及過程。最後分別再對每個實驗中所遇到的問題提出各種解決的方式和建議。

關鍵字

光學測距法 ； 相對深度資訊 ； 波動光學 ； 光學成像系統 ； 影像處理

並列摘要

In this dissertation, an optical measurement method for middle- and long-distance depths is expected to be established with benefits of distinguishing the relative depth between different objects. Besides, advantages and shortcomings of several methods for acquiring the depth information will be discussed by classification of different observing distance from short-distance, middle-distance to long-distance, respectively. In the process of building the optical measurement method for middle- and long-distance depths, the concept of whole research and the ideal experimental structure will firstly be brought up. Secondly, all the ideas of experiments will be verified by simulations within the the wave optics. Before all the experiments begin, the diameters of optical devices and components are chosen by simulations for achieving purposes we set.

The main structure of this research is to set up an imaging system in front of an observed object. After that, a pinhole will be placed in the focal plane of the focused image. By the structure of pinhole, we could observe the difference of image and the trend of divergence. Thus, the depth information is able to be gained by all the data we measured. All the optical devices and components like the observed objects, types of light sources, the Complementary Metal Oxide Semiconductor (CMOS) image sensor and the process of analyzing images will also be discussed. In the long run, solutions and suggestions in each experiment will be bought up in the last chapter.

並列關鍵字

Optical Measurement Method ； Relative Depth Information ； Wave Optics ； Optical Imaging System ； Image Processing

參考文獻

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