Modular cross connect system with 3D-MEMS for optical telecommunication networks
A modular cross connect system for optical telecommunication networks has the optical unit divided in at least two main bodies with one section for connection comprising the collimators and a main commutation section with MEMS devices. The first section is a fixed part while the second section is a readily removable section. The two sections face each other through a window and, in the first section, optics are provided for steering all or part of the optical signals from and to the main MEMS unit to a MEMS standby or protection plane to allow replacement of the main MEMS unit without interrupting service.
1. A cross connect system for optical telecommunication networks, comprising: input and output ports interconnected by means of switching members; and a connecting section including, in turn, said ports and a main switching section having the switching members as MEMS devices, the switching section being contained in a removable box, and the connecting section including optical steering means for intercepting on command optical paths between the two sections from and to the connecting section to steer them from the main switching section towards a protective switching section, the MEMS devices being supported in the box by a support system arranged to provide controlled movement of the MEMS devices for alignment of the MEMS devices with the optical paths.
2. The system in accordance with claim 1 , in that the protective switching section comprises additional switching members as MEMS devices which are housed in an additional removable box.
3. The system in accordance with claim 2 , in that at least the switching means are housed in a removable box for replacement.
4. The system in accordance with claim 1 , and sensors in the switching section, for detecting input optical power to, and output optical power from, the main switching section.
5. The system in accordance with claim 4 , and sensors in the connecting section, for detecting input optical power to, and output optical power from, the main switching section.
6. The system in accordance with claim 5 , in that the sensors are illuminated CCDs intercepting part of the optical paths with semireflecting mirrors.
7. The system in accordance with claim 1 , in that the switching sections are a plurality, and in that the connecting section comprises a unit made up of an array of collimators and optical steering means for each switching section.
8. The system in accordance with claim 7 , in that each collimator array and optical steering means unit is in turn housed in a replaceable box.
9. The system in accordance with claim 8 , in that each removable box comprises means for alignment detection and means for alignment adjustment.
10. The system in accordance with claim 7 , in that at least the steering means of each unit are housed in replaceable removable boxes.
11. A telecommunication system comprising a cross connect system in accordance with claim 1 .
12. The system in accordance with claim 1 , in that the support system is arranged to align the optical paths in an approach direction and in two directions transverse to the approach direction.
13. The system in accordance with claim 1 , further including guides extending in an approach direction to the connecting section along which the switching section is arranged to run to provide said alignment
14. The system in accordance with claim 1 , in that the MEMS devices include planes of mirrors, and in that the system includes a single plate on which the planes of mirrors are fixed.
15. The system in accordance with claim 14 , in that the plate is arranged to be moveable in relation to the switching section in two directions transverse to an approach direction.
16. The system in accordance with claim 15 , including actuators for moving the plate.
17. The system in accordance with claim 16 , including control logic for controlling the actuators.
18. The system in accordance with claim 17 , in that the control logic is arranged to control actuators by means of a closed loop to compensate continuously for mechanical shifts.
19. The system in accordance with claim 1 , further comprising a laser position sensing system for sending a laser beam between the connecting section and the switching section for verification of the alignment.
20. The system in accordance with claim 19 , in that the laser position sensing system includes a position sensor which comprises four quadrants for monitoring a position of the laser beam.
21. A cross connect system for optical telecommunication networks, comprising: input and output ports interconnected by means of switching members; and a connecting section including, in turn, said ports and a main switching section having the switching members as MEMS devices, the switching section being contained in a removable box, and the connecting section including optical steering means for intercepting on command optical paths between the two sections to steer them from the main switching section towards a protective switching section, the optical steering means being arranged on optical paths between collimators and optical connection windows with the main switching section.
22. A cross connect system for optical telecommunication networks, comprising: input and output ports interconnected by means of switching members; and a connecting section including, in turn, said ports and a main switching section having the switching members as MEMS devices, the switching section being contained in a removable box, and the connecting section including optical steering means for intercepting on command optical paths between the two sections to steer them from the main switching section towards a protective switching section, the main switching section box and the protective switching section box being arranged side by side and facing each other with a respective optical path passage window on a corresponding connecting section window.