基片傳輸型全像結構之多波段波長區分解多工元件

Abstract

本論文利用基片型全像片提出一個多波段波長區分解多工器的疊層結構 . 此結構為多個基板疊層而成, 具有垂直耦合輸入及輸出, 穩定不受干 擾, 和高的波長頻寬等優點; 實驗上, 每一層基片型全像片是對不同的中 心波長所設計的, 而且利用重鉻酸銨明膠的體基型全像片和短波長拍製長 波長重建技術來製作. 所製作的基片型全像片單元具有高效率 ,與入射光 偏極無關, 和波長密分的特性. 此一疊層結構的第一層可將某一中心波段 的光訊繞射和密分而讓其它波段的光訊不受影響的通過,而另一層的可對 另一中心波段的光訊繞射密分. 每一層基片負責一個波長光訊的密分. 利 用這種結構, 我們可以提升光學傳輸系統, 光纖感測網路, 和多波長光學 連接的容量. A compact multiband wavelength-division-demultiplexer using subst rate-mode holograms is presented. It has the advantages of reduci ing alignment sensitivity over cinventional holographic optical e lemants,stable,free from EMI,and high wavelength bandwidth. Each SMH is designed for a central wavelength and fabricated with volu holograms formed in dichromated gelatin emulsioms. The fabricated SMH unit has the characteristics of polarization independent, hig h efficiency, easy alignment, and dense wavelength division. Casc aded SMH structure can diffract one band of signal in first layer and others pass uneffected.The second layer diffract another band of signal.The diffracted band of signal propagate and separate through the substrate by total internal reflection and grating dispersion effect. Every layer is responsible for one band of wavelength division. Using this structure,we can improve the capacity of optical transmission system, optical fiber senser network, and optical multi-wavelength interconnection.