Polarization-Independent Filter Based on 2-D Crossed Grating Under Oblique Incidence
The existing polarization-insensitive filters based on two dimensional (2-D) grating are mostly under normal incidence. However, in filtering optical devices, the normal incidence regime is usually avoided because it requires the use of beam separators which yields a loss of efficiency. Herein, we p...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2018-01-01
|
| Series: | IEEE Photonics Journal |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/8466960/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The existing polarization-insensitive filters based on two dimensional (2-D) grating are mostly under normal incidence. However, in filtering optical devices, the normal incidence regime is usually avoided because it requires the use of beam separators which yields a loss of efficiency. Herein, we present a compact method to realize polarization-independent filter under oblique incidence, which is implemented on 2-D crossed grating in the telecommunication region. Plane of incidence is set to be in <italic>xz</italic> plane and three different polarization angles (0°, 45°, and 90°) are used to demonstrate the polarization-insensitivity. Realization of the polarization-insensitivity of the 2-D filter is based on the split feature under oblique incidence, according to the analysis of the physical mechanism. The location of the polarization-independent resonance is mainly determined by the grating period along x-axis and will right shift with increasing the period. Results show that the polarization-insensitive resonances occur at 1356.9 nm, 1372.6 nm and 1398.5 nm when the grating periods along x-axis are 830 nm, 850 nm and 870 nm, respectively. Moreover, the results and methods provided herein can be applied to search for the polarization-insensitive resonances of the 2-D grating with other planes of incidence. |
|---|---|
| ISSN: | 1943-0655 |