mems optical switches xiaobo hou ecee 641 march. 13, 2003
TRANSCRIPT
Introduction
Why optical switches– Explosive network traffic– Rapidly growing data rate and port count– Bottleneck due to conventional OEO switches
(bandwidth, bit error rate and capacity mismatch)
– Cost effective• Competition is in the
high date rate range
MEMS Optical Switches
What is MEMS– Micro-Electro-Mechanical System
What is MEMS optical switches– Steerable micromirror array to direct optical
light from input port to its destination port.
– System-in-a-chip
3D MEMS Switches
Mirrors can be tilted to any angles
N or 2N mirrors accomplishing non-block switching
Good scalability
How to design
Paraxial Gaussian beam model
Optimize beam size W0, Given separation between mirror arrays
0w
Z R
2
00
2
0 11)(
w
zw
z
zwzw
R
2
1
)(0
z
w opt
Actuating Mechanism (I)
Electrostatic– mirrors are tilted by electrostatic force
between opposite charged plates
Actuating Mechanism Comparison
Actuating Mechanisms
Advantages Disadvantages
Electrostatic Well understood Good repeatability
Nonlinearity in force-voltage relationship,
High driving voltages. Electromagnetic Large force
High linearity Low driving
voltages
Shielding magnetic devices
Reliability to be proved
Scratch Drive Actuator(SDA)
No holdup voltage required
Movement in small steps (10nm)
(N/A)
Performance and Challenges
Switching speedsubmicrosecond
Scalability512 512
Insertion Loss3-7 dB
Power dissipationless than electrical switch core
? Controllability? Reliability? Manufactuability? Serviceability? standardization