| 摘要 |
PURPOSE:To attain operations such as write, storage and readout as an optical signal without being converted into an electric signal by circulating an inputted signal light to an annular optical circuit and controlling the polarized wave state depending on the input state of a control section to a polarized wave rotating element. CONSTITUTION:A signal light is made incident in an input terminal of a polarized wave beam splitter 1 at write and introduced to the annular optical circuit 3, and made incident in a polarized wave rotating element 2. In this case, a control signal CTL is inputted to the polarized wave rotating element 2, a signal light is converted from the Y polarized wave state into the X polarized wave state, radiates to the annular circuit 3 via an output terminal of the polarized wave beam splitter 1 again and the write is finished. Moreover, when the signal light of X polarized wave circulat ing in the annular optical circuit 3 is made incident in the polarized wave rotating element 2 at readout, the control signal CTL is inputted to the polarized wave rotating element 2, the signal light is converted into the Y polarized wave and the incident light into the polarized beam splitter 1 comes out of the annular circuit 3. Thus, operations such as write, storage and readout as an optical signal are implemented without being converted into an electric signal. |
