The 1480nm Polarization Maintaining Isolator is a two port micro-optic device built with PM panda fiber. The PM isolator features low insertion loss, high isolation, high extinction ratio and high reliability and stability. The device guides optical light in one direction and eliminates back reflection and back scattering in the reverse direction. The device can be built with bare fiber, or 900um jacket cable.
The 1480nm Polarization Maintaining Isolator is a two port micro-optic device built with PM panda fiber. The PM isolator features low insertion loss, high isolation, high extinction ratio and high reliability and stability. The device guides optical light in one direction and eliminates back reflection and back scattering in the reverse direction. The device can be built with bare fiber, or 900um jacket cable. The PM Panda Fiber Isolator is widely used in amplifier systems, fiber optic systems and fiber lasers.
If you do not see a standard isolator that meets your needs, we welcome the opportunity to review your desired specification and quote a custom isolator. Requests for custom fiber pigtails, different wavelengths and handling power of operation or other specific needs will be readily addressed. DK Photonics can respond to custom requirements with short lead times.
Parameter |
Unit |
Specification |
|||
Operating wavelength |
nm |
1480 |
|||
Grade |
- |
P |
A |
P |
A |
Type |
- |
Single Stage |
Dual Stage |
||
Operating Wavelength Range |
nm |
±20 |
|||
Typ. Insertion Loss at 23℃ |
dB |
0.4 |
0.5 |
0.5 |
0.6 |
Max. Insertion loss at 23℃ |
dB |
0.55 |
0.65 |
0.65 |
0.8 |
Typ. Peak Isolation at 23℃ |
dB |
42 |
40 |
58 |
55 |
Min. Isolation at 23℃ |
dB |
28 |
26 |
48 |
45 |
Extinction ratio (Type B) |
dB |
≥20 |
≥18 |
≥20 |
≥18 |
Extinction ratio (Type F) |
dB |
≥22 |
≥20 |
≥22 |
≥20 |
Return loss (input/output) |
dB |
≥50/50 |
|||
Fiber Type |
- |
PM1550-XP |
|||
Max. Power Handling (CW) |
W |
0.3, 1, 2, 5, 10 |
|||
Max. Peak Power for Pulse |
kW |
/ |
|||
Max. Tensile Load |
N |
5 |
|||
Operating temperature |
℃ |
-5℃ ~ + 70℃ |
|||
Storage temperature |
℃ |
-40℃ ~ + 85 ℃ |
|||
Dimensions |
mm |
Ф5.5× L35(<5W), 65x12x9(>5W) |
|||
“B” for Both axis working, “F” for Fast axis blocking |
When you inquire, please provide the correct P/N number according to our ordering information and attach the appropriate description would be better. If need any connector, we do not recommend choosing a 250μm bare fiber pigtail.
① |
② |
③ |
④ |
⑤ |
⑥ |
⑦ |
⑧ |
Type |
wavelength |
Grade |
Power Handling |
Axis Alignment |
Pigtail Diameter |
Fiber Length |
Connector |
S: Single stage D: Dual stage |
14:1480nm XX: Others |
P:P Grade A: A Grade |
L: <0.3W 1:1W 2:2W 5:5W 10:10W |
B: Both axis working F: Fast axis blocking |
25:250μm bare fiber 90:900μm Loose Fiber XX: Others |
08:0.8m 10:1.0m XX: Others |
00: None FP: FC/PC FA: FC/APC XX: Others |
Part Number Example: PMISO-S-14-P-L-B-90-10-FA
Description: 1480nm Polarization Maintaining single stage Isolator - 300mW, P grade, both axis working, 1.0m Fiber length with 0.9mm OD loose tube, and FC/APC connectors at all ports.
If you need to customize other specifications, please provide detailed description for your requirement.
Function
An optical isolator is a passive magneto-optic device that only allows light to travel in one direction. Isolators are used to protect a source from back reflections or signals that may occur after the isolator. Back reflections can damage a laser source or cause it to mode hop, amplitude modulate, or frequency shift. In high-power applications, back reflections can cause instabilities and power spikes.
An isolator's function is based on the Faraday Effect. In 1842, Michael Faraday discovered that the plane of polarized light rotates while transmitting through glass (or other materials) that is exposed to a magnetic field. The direction of rotation is dependent on the direction of the magnetic field and not on the direction of light propagation; thus, the rotation is non-reciprocal. The amount of rotation β equals V x B x d, where V, B, and d are as defined below.
Figure 1. Schematic diagram of Faraday effect
Faraday Rotation
β = V x B x d
1. Definition
The single mode optical isolator is a passive magneto-optical device which uses the Faraday effect of magneto-optic crystal to isolate the reflected light and only allows the light to transmit in a single direction. The optical fiber isolators are used to protect light sources from adverse effects caused by back-reflection or signal.
2. Characteristic
3. Description
1). Introduction to the working principle of polarization dependent isolator
Polarization-Dependent Isolators-Polarizer Type Polarization Dependent Isolator
The Forward Mode
In this example, we will assume that the input polarizer's axis is vertical (0° in Figure 2). Laser light, either polarized or unpolarized, enters the input polarizer and becomes vertically polarized. The Faraday rotator will rotate the plane of polarization (POP ) by 45° in the positive direction. Finally, the light exits through the output polarizer which has its axis at 45°. Therefore, the light leaves the isolator with a POP of 45°.In a dual-stage isolator, the light exiting the output polarizer is sent through a second Faraday rotator followed by an additional polarizer to achieve greater isolation than a single-stage isolator.
The Reverse Mode
Light traveling backwards through the isolator will first enter the output polarizer, which polarizes the light at 45° with respect to the input polarizer. It then passes through the Faraday rotator rod, and the POP is rotated another 45° in the positive direction. This results in a net rotation of 90° with respect to the input polarizer, and thus, the POP is now perpendicular to the transmission axis of the input polarizer. Hence, the light will either be reflected or absorbed. to achieve the function of light transmission in a single direction. This enables light to transmit in a single direction.
Figure 2. Structure schematic diagram of polarization dependent isolator
Usually, the PM fiber optical isolator with fast axis blocked, slow axis working is based on this structure. However, due to the limited withstand power of the polarizer, the average power of the isolator of this structure should not be greater than 2w, and higher power is recommended displacer type polarization dependent isolator. If you need to work with both axis, please refer to the principle of wedge type polarization independent isolator.
The PER is measured using the following test measurement setup:
Figure 5. schematic diagram of measurement of polarization extinction ratio setup
Connect the components as shown above. Note that it is necessary to ensure that the panda eye of the PM fiber is perfectly aligned.
Adjust the rotatable polarizers sequentially until a minimum power value is measured by the power meter. Record the measured value as Pmin(dB).
Rotate the rotatable polarizers mount by 90°. Then record the measured value as Pmax(dB).
After Pmin and Pmax are measured, the extinction ratio can be calculated: PER(dB)= Pmax(dB) - Pmin(dB)
DK Photonics can provide a complete set of equipment/devices for the above measurement of extinction ratio setup, if you need it, please contact our sales: sales@dkphotonics.com.