使用全像空間偏離偏極器之波長交織雙向光學循環器

Abstract

利用耦合波理論設計出全像空間偏離偏極器，並以短波長拍攝長波長重建技術加上感光乳劑厚度收縮與折射率變化的修正條件，製造出品質良好可取代傳統的晶體式偏離偏極器；且將它應用於傳統的四埠循環器，進而將此四埠循環器加以改良，提出新型多埠偏極獨立準循環器。其次結合Lyot-Őhman filter的波長交織術，提出新的四埠偏極獨立波長交織雙向循環器；又將此循環器加以改進，進一步提出效能更高的多埠偏極獨立波長交織雙向準循環器，接著討論各循環器的操作原理及其功能。為了驗證這些新穎循環器的效能，利用所製造的全像偏離偏極器、半波片、法拉第旋轉器、薄玻璃片、面鏡，以及Lyot-Őhman filter組裝這四種循環器並測量其特性；所提出的元件均具有與偏極無關、低偏極模色散、高隔絕性、易製作及易成模組等優點。

Based on the coupled-wave theory, a new type of holographic spatial walk-off polarizer is designed. It can be fabricated by using the shorter-wavelength construction for longer-wavelength reconstruction technology and the compensation method to physically correct the influences due to the thickness shrinkage and refractive-index shift of the recordingmaterial. It is better than the conventional one made of crystals. It is applied to improve the conventional 4-port optical circulator. This new type of 4-port optical circulator is modified and applied to develop a new multiple-port polarization-independent optical quasi-circulator. Next, a novel 4-port polarization-independent wavelength-interleaving bidirectional circulator is proposed with the wavelength-interleaving characteristics of the Lyot-Őhman filter and the fabricated holographic spatial walk-off polarizers. Then, it is introduced to develop a functional multiple-port polarization-independent wavelength-interleaving bidirectional quasi-circulator. In addition, the prototypes of these four circulators are assenbled and experimentally tested. Their operating principles and performances are discussed. They have such merits as polarization-independence, compactness, high isolation, lack of polarization mode dispersion and ease of fabrication.