4 Ports C+L 1520~1620nm Polarization Insensitive Optical Circulator

Fiber-Online’s Four-port Optical Circulator is a special type of circulator that has one input (port 1), one output (port 4) and two common ports (port 2&3). The light goes through port 1 to port 2. At port 2, any incoming light is guided to port 3 as output, while all input from port 3 is guided to port 4 as output.
Compared to three-port circulator, four-port device has one additional bi-directional port. Hence, it can be used to construct more flexible or more complex optical fiber sub-systems, such as add/drop module, mux/demux module, multi-port bi-directional splitters, WDM optical router, etc.

Characteristics

• Low Back Reflection
• High Extinction Ratio
• Low Insertion Loss
• High Return Loss

Applications

• DWDM system
• Add-Drop Multiplexing
• Fiber Amplifier
• Fiber Sensor
• Chromatic Dispersion Compensation Devices
• Fiber Bragg Grating
• Polarization maintaining optical system

Application Diagram

Below are Three Port Circulator application for your reference.

	As the picture shows: The input DWDM channels are coupled into Port 1 of the device with a FBG device connected to Port 2. The single wavelength reflected from the FBG then reenters the Circulator in Port 2 and is routed accordingly to Port 3. The remaining signals pass through the FBG and exit on the top fiber.
Circulator used to drop an optical channel from a DWDM system using a Fiber Bragg Grating.

	As the picture shows: A Circulator is located at both ends of the fiber. Each Circulator functions to add a signal in one direction while removing the signal in the other. See the example to the left.
Circulator can be used to send optical signals through a single fiber in two directions.

Dimension

Sample Picture

Order Information

wavelength	Type	Grade	Pigtail Type	Length	Connector
1310nm 1480nm 1550nm 1585nm 1520~1620nm	3 Ports 4 Ports	P Grade	250um bare fiber 900um loose tube 3mm loose tube 2mm loose tube	0.5m 0.8m 1.0m 1.5m 2.0m Custom	None FC UPC/APC SC UPC/APC LC UPC/APC ST UPC/APC E2000 UPC/APC MU

Note:
1. Wavelength: Fiber-Online can customize any other wavelengths according to your requirement.
2. Length: The default length for the cable is 1M, Fiber-Online could also provide 0.5M,0.8M,1.5M, 2.0M ,etc.
3. Connector: Each port of the Circulator could be with any connector such as FC/LC/SC/ST,etc. Please contact us by email to [email protected] or call at +86 1 86 2786-1199 if you have any requirement for it.
 

Type Parameter	3 Port	4 Port
Operating wavelength (nm)	1310, 1480,1550,1585,(+/-30)	C+L(1520~1620)	1310,1480,1550,1585,(+/-30)	C+L (1520~1620)
Isolation (λc,23℃ all sop) (dB)	≥40	≥40	≥40	≥40
Isolation (Over all λ, T, sop) (dB)	≥35	≥30	≥35	≥30
Insertion Loss (λc,0~70℃ all sop) (dB)	Grade P	≤0.8	≤1.1	≤0.8	≤1.2
Grade A	≤1.0	≤1.2	≤1.0	≤1.3
PDL (dB)	≤0.15	≤0.20
Return loss (dB)	≥50
PMD (ps)	≤0.1
Directivity	≥50
Power handling (mW)	≤300
Fiber Type	SMF-28e
Operating temperature (℃)	0 ~ +70
Storage temperature (℃)	-40 ~ +85
Package Dimensions (mm)	For bare fiber of 900um loose tube	φ5.5×L50(P2)	φ5.5×L68(P5)	φ5.5×L64(P8)
For 3mm cable	L98XW14.5XH8.5(P6)	L90XW20XH9.5(P9)	L80xW12xH10(P7)