The document discusses mechanical and MEMS optical switches used in optical fiber communication systems, highlighting their roles in switching optical signals and enabling optical cross-connect technology. It outlines the working principles, advantages, and disadvantages of both switch types, noting that MEMS optical switches offer compactness and fast switching while mechanical switches provide low insertion loss and mature technology. It also mentions HYC Co., Ltd's development of MEMS optical switch products with scalable configurations and extensive customization capabilities.

1. Mechanical Optical Switch & MEMS Optical Switch
In the optical fiber communication system, the optical switch (OS) is mainly used to
realize the physical switching of optical signals or other logical operations in the optical
path, and is mostly used in the optical cross-connect (OXC) technology as a key device
for optical switching.
Optical switch is a multiport device. The port configurations include 2×2, 1×N, M×N.
Optical switches have a wide range of applications in optical fiber communication
systems. According to the realization technology can be classified as mechanical
optical switch, thermo-optical switches, acoustic-optical switches, electro-optical
switches, magneto-optical switches, liquid crystal optical switches and MEMS optical
switches, etc. Mechanical optical switch and MEMS optical switch are the two widely
used optical switches.
The working principle of the mechanical optical switch is to redirect the optical signal
by physically moving the optical fiber with the aid of a mechanical device. By moving
the prism or directional coupler, the light at the input end is directed to the desired
output port. There are three main types of mechanical optical switches: one is to use
prism to switch the optical path technology, the other is to use mirror switching
technology, and the third is to switch the optical path by moving optical fibers.
Mechanical optical switch
The MEMS optical switch is based on a micro-electro-mechanical system, which uses
an optical micro-mirror or an optical micro-mirror array to change the direction of the
beam to switch the light path. The principle of the MEMS optical switch is very simple.
When the light is exchanged, the angle of the MEMS micro mirror is moved or changed
by the drive of electrostatic force or magnetic power, and the input light is switched to
the different output terminals of the optical switch to realize the switching and on-off
of the optical path. The schematic diagram is shown below:

2. The principle of mems optical switch
The principle of the 2×2 optical switch is shown in Fig. Four waveguides are aligned in
four directions and a vertical MEMS mirror is aligned in 45° direction. When the mirror
is not inserted into the optical path, optical beams from waveguides 1 and 2 are
coupled to waveguides 3 and 4, respectively. The port connection is 1→3 & 2→4,
which is the bar state. When the mirror is inserted into the optical path, optical beams
from waveguides 1 and 2 are reflected by the mirror and then coupled to waveguides
4 and 3, respectively. The port connection is switched to 1→4 & 2→3, which is the
cross state.
Principle of the 2×2 MEMS optical switch, left: bar state, right: cross state
MEMS optical switch

3. Advantages Disadvantages
Mechanical Optical
Switch
Low insertion loss
High isolation
Independent of
wavelength and
polarization
Mature production
process and technology
Long switching time
Large size
Not conducive to
making a large optical
switch matrix
MEMS Optical Switch
Small size and high
integration
High scalability
Low polarization loss
Fast switching
Higher cost
High production process
and technical
requirements
With the rapid development of optical communications, the status of optical
interconnection and optical switching as optical network nodes is becoming more and
more important, and the application of optical switches is becoming more and more
extensive. MEMS optical switches have the advantages of compactness, fast switching
speed, and easy expansion. At the same time, they have the low insertion loss, low
crosstalk, low polarization sensitivity, high extinction ratio and high switching speed of
waveguide switches, small size, and easy expansion of mechanical optical switches.
The advantages of large-scale integration. It will be the mainstream direction of the
development of high-capacity switching optical network switches.
HYC independently develops MEMS optical switch series products, with 1×2, 1×4, 1×N
channel configuration, which can be expanded up to 1×48 channels, and has the
advantages of low power consumption, integration, fast response speed, and cost
reduction. Headquartered of HYC Co., Ltd is in Qingyuan Guangdong, and HYC has R&D
centers in Wuhan and Shenzhen. It has more than 1,000 employees and has more than
20 years of OEM and ODM experience. It provides one-stop customization for the
design, R&D and manufacturing of optical communication optical passive components.
www.hyc-system.com