1 × 2 Optical Router With Control of Output Power Level Using Twisted Nematic Liquid Crystal Cells

Broadband 1×2 liquid crystal router with low thermal dependence for polymer optical fiber networks

“…The proposed PR design allows a significant improvement of the spectral response of LC optical routers, as in those previously reported [10,11,19,20], in a broadband range, and may even improve the response of LC devices reported recently [23]. The experimental results show that the proposed router has quite similar values of IL in both outputs (OFF and ON states) in the range from 400-nm, as well as CT values lower than À18.68 dB.…”

“…Usually, and especially in applications where channel equalization is needed, LC-ORs use twisted nematic (TN) LC cells, acting as polarization rotators (PRs) with a continuous operation mode (intermediate transmission levels) [19,20]. However, their performance is optimum only for specific wavelengths (Mauguin Minima) [21].…”

Recent Advances in Wavelength-Division-Multiplexing Plastic Optical Fiber Technologies

“…10.b additionally provides the possibility of stabilizing the optical power that is transmitted by each port. This feature was reported in [62]. In that scheme, TN-LC 2 and 3 have both an input and an output crossed polarizer, with the input polarizer parallel to the respective polarization component transmitted by the PBS.…”

“…Figure 12 shows an example of the performance of the broadband 1×2 LC-OR reported in [69]. The proposed design illustrated above is composed by 3 LC cells and allows a significant improvement of the spectral response of LC optical routers, compared to those previously reported [43,62,70] in a broadband range. The proposed router has quite similar insertion loss values in both outputs in the range from 400 nm to 700 nm, as well as crosstalk values lower than -18.7 dB, as shown in Fig.…”

“…Fig. 11 shows an example of the power stabilization capacity of the router reported in [62]. LC-OR based on nematic LC cells cannot respond faster than several microseconds.…”