Packaged optical device stack
View Patent ↗A packaged stack of optical devices includes two or more WDM optical devices, the stack having a reduced per-channel manufacturing cost and an improved mean time between failure relative to individual optical devices. WDM optical devices, which may be contained in a packaged stack, include wavelength selective switches, optical add-drop multiplexers, and dynamic gain equalizers. The optical switching devices in the stack may be configured so that one or more optical elements are shared by multiple switching devices. Optical components that may be shared between the switching devices contained in the stack include cylindrical lenses, diffraction gratings, mirrors, and beam steering units.
1. A packaged optical device comprising:
a first WDM optical device;
a second WDM optical device; and
a common housing in which the first and second WDM optical devices are stacked,
wherein light beams transmitted through the first WDM optical device travel along a first set of optical paths and light beams transmitted through the second WDM optical device travel along a second set of optical paths, and wherein the optical paths in the first set do not intersect the optical paths in the second set and wherein the first WDM optical device and the second WDM optical device share one or more optical elements, including a common beam polarization and steering unit having a liquid crystal array and a birefringent element.
2. The packaged optical device according to claim 1 , wherein the first WDM optical device and the second WDM optical device are wavelength selective switches and share a common diffraction grating.
3. The packaged optical device according to claim 1 , wherein the shared optical elements include a beam polarization unit.
4. The packaged optical device according to claim 3 , wherein the beam polarization unit includes an LC cell.
5. The packaged optical device according to claim 1 , wherein each of the first WDM optical device and the second WDM optical device has N input ports and M output ports, and wherein N is any positive integer and M is any positive integer greater than or equal to 2.
6. A packaged optical device comprising:
a first WDM optical device having N input ports and M output ports;
a second WDM optical device having N input ports and M output ports; and
a common housing in which the first and second WDM optical devices are stacked,
wherein the first WDM optical device and the second WDM optical device share one or more optical elements, including a common beam polarization and steering unit having a liquid crystal array and a birefringent element, and wherein N is any positive integer and M is any positive integer greater than or equal to 2.
7. The packaged optical device according to claim 6 , wherein light beams transmitted through the first WDM optical device travel along a first set of optical paths and light beams transmitted through the second WDM optical device travel along a second set of optical paths, and the optical paths in the first set do not intersect the optical paths in the second set.
8. The packaged optical device according to claim 7 , wherein the first WDM optical device and the second WDM optical device are wavelength selective switches and share a common diffraction grating.
9. The packaged optical device according to claim 7 , wherein the shared optical elements include a beam polarization unit.
10. The packaged optical device according to claim 9 , wherein the beam polarization unit includes an LC cell.
11. The packaged optical device according to claim 6 , wherein the first and second WDM optical devices are optical communication devices of the same type.
12. The packaged optical device according to claim 11 , wherein the first and second WDM optical devices comprise wavelength blockers.
13. A wavelength selective switch comprising:
a first set of input and output ports;
a second set of input and output ports;
a light dispersing element for dispersing a first input light beam received through the first set of input and output ports into a first set of multiple wavelength components and a second input light beam received through the second set of input and output ports into a second set of multiple wavelength components;
a first optical switch for receiving the first set of multiple wavelength components and directing them to one of multiple directions; and
a second optical switch for receiving the second set of multiple wavelength components and directing them to one of multiple directions,
wherein the first and second sets of input and output ports are stacked within a common housing and the first and second optical switches are stacked within the common housing and the first and second optical switches share one or more optical elements, including a common beam polarization and steering unit having a liquid crystal array and a birefringent element.
14. The wavelength selective switch according to claim 13 , wherein the light dispersing element is configured to receive the first set of multiple wavelength components that passed through the optical switch and combine them into a single output light beam and to receive the second set of multiple wavelength components that passed through the optical switch and combine them into a single output light beam.
15. The wavelength selective switch according to claim 13 , wherein each of the first optical switch and the second optical switch comprises a beam polarization unit and a beam steering unit that switches the optical path of the multiple wavelength components based on their polarization state.
16. The wavelength selective switch according to claim 15 , wherein the beam steering unit comprises one of a birefringent crystal and a Wollaston prism.
17. The wavelength selective switch according to claim 13 , wherein light beams transmitted through the first optical switch travel along a first set of optical paths and light beams transmitted through the second optical switch travel along a second set of optical paths, and the optical paths in the first set do not intersect the optical paths in the second set.
18. The wavelength selective switch according to claim 13 , wherein the first set of input and output ports includes N input ports and M output ports and the second set of input and output ports includes N input ports and M output ports, and wherein N is any positive integer and M is any positive integer greater than or equal to 2.
19. The wavelength selective switch according to claim 13 , wherein the first and second sets of input and output ports are vertically stacked within the common housing and the first and second optical switches are vertically stacked within the common housing.