微中子望遠鏡之光學系統

Abstract

微中子望遠鏡是設計來偵側τ微中子的。假使它被觀察到，就證明了μ微中子與τ微中子之間的振盪。另外偵測微中子也可用來分析高能宇宙射線的起源。 望遠鏡中的光學系統是用來收集τ微中子在地表中衰變所造成的契倫斜夫光的空氣簇射，接著這些光會被傳到後面電子系統來分析。 我們使用光學模擬軟體來設計及最佳化我們的光學系統。首先我們試著設計了一些菲涅爾透鏡的光學系統，另外我們也買了一片商業用型的菲涅爾透鏡來分析它的模型。但菲涅爾透鏡系統不能達到我們的要求，所以接著我們設計了一個斯密特光學系統，而它能符合微中子望遠鏡的要求，所以它就被採用為微中子望遠鏡的光學系統。此外，我們也做了蒙地卡羅模擬來分析光的損失量。最後，我們製作出了望遠鏡，並且對其系統內的透鏡、反射鏡及整個望遠鏡做了一些測試。我們量了透鏡的曲率半徑，非球面透鏡的成像位置以及整個望遠鏡的光點大小，這三者的量測結果都有符合我們的設計要求。

The neutrino telescope (NuTel) is designed to detect the tau neutrino. If it is observed, the oscillation,muon neutrino to tau neutrino is proved. Also detecting neutrinos can be used to analyse the origin of UHECR (ultra high energy cosmic ray). The optical system is used to watch the Cherenkov light of the air shower particles which arose from decay of tau neutrino in the earth. Then the signal will be transferred to the rear electronic system for analysis. Primarily we used optical simulation software to design and optimize. Fresnel lens system design was the first try and a commercial Fresnel lens was bought to analyse its model to use at the same time. The second type of design is Schmidt mirror system and it matched the requirement of NuTel. Therefore it is adopted as the optical system of NuTel. Also some Monte Carlo simulations of transmittance were done to evaluate the loss of light. Finally, we constructed the telescope and performed measurments for the lens, the mirror, and the telescope. The imaging position of the aspherical lens was measured. The radius of curvature of the mirror was measured. The spot size of the whole system was measured. All the measrement results satisfied the design goals.