Coherent Optical Circuit Switch

Optical Circuit Switch

Coherent (formerly II-VI / Finisar) is developing optical circuit switches. This article introduces important points to consider when selecting an optical circuit switch and Coherent 's lineup of optical circuit switches.

Introduction

This section introduces the important points and main technical methods when selecting an Optical Circuit Switch (OCS).

Important points when selecting

1. Reliability

To reduce the risk of failure, reliability, such as a long-term operational track record, is important.

2. Number of ports (Radix/Scalability)

The required switch scale (number of ports) varies depending on the application. AI networks and data center networks may require hundreds of ports. It may also be necessary to check scalability, such as support for future expansion.

3. Optical insertion loss

Insertion loss (dB) is important for long transmission distances and high-bandwidth communications. Selecting a low-loss OCS can alleviate transmission distance constraints.

4. Switching Speed

AI networks may require switching speeds of msec to μsec.

Main technology method

Currently, there are five main OCS technology methods:

Below is an example comparing switching time, insertion loss, drive voltage, crosstalk, and mechanical drive units.

Core Technology	Switch Time	Insertion Loss	Drive voltage	Crosstalk	Mechanical Drive
Digital Liquid Crystal	○	○	◎	◎	Nothing
MEMS	○	○	△	△	Yes
Robotic	△	◎	◎	◎	Yes
Piezoelectric	◎	○	○	△	Yes
SiPh	◎	△	○	△	Yes