| 摘要 |
PURPOSE:To provide a smaller insertion loss, smaller size and larger number of terminals by inserting a hologram element having >=1 pairs of holograms into an optical path. CONSTITUTION:The hologram element 5 is disposed between a single fiber plug 3 and a multifiber plug 13. The hologram element 5 is constituted by simmetrically inserting two hologram medium layers 7, 17 between three sheets of glass plates 8, 18, 28 and forming the plural holograms 6, 16 so as to make pairs respectively on the respective hologram medium layers 7, 17. Collimated beams of light refract merely when the collimated beams of light are made incident diagonally on the single hologram but the deflection effect thereof is offset by the passage through the holograms 6, 16 and the collimated beams of the light are eventually moved parallel. Not so much high positioning accuracy is, therefore, required if the holograms are previously formed sufficiently large to the luminous fluxes. The miniaturization of the device and the increase in the number of the switching terminals are possible in this way. |
