The 1064nm 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 1064nm 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.
PARAMETER | UNIT | SPECIFICATION | |||
Operating wavelength | nm | 1064/1080/1150 | |||
Grade | – | P | A | P | A |
Type | – | Single Stage | Dual Stage | ||
Operating Wavelength Range | nm | ±5 | |||
Typ. Insertion Loss at 23℃ | dB | 1.5 | 1.6 | 2.3 | 2.6 |
Max. Insertion loss at 23℃ | dB | 1.8 | 2.2 | 3.2 | 3.4 |
Typ. Peak Isolation at 23℃ | dB | 35 | 32 | 55 | 52 |
Min. Isolation at 23℃ | dB | 30 | 28 | 45 | 42 |
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 | – | PM980-XP / PM1060L Fiber or other | |||
Max. Power Handling (CW) | mW | 200 | 100 | ||
Max. Peak Power for Pulse | kW | 1, 5,10 | |||
Max. Tensile Load | N | 5 | |||
Operating temperature | ℃ | -5℃ ~ + 70℃ | |||
Storage temperature | ℃ | -40℃ ~ + 85 ℃ | |||
Dimensions | mm | Ф5.5× L35 | |||
“B” for Both axis working, “F” for Fast axis blocking |
①
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②
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③
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④
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⑤
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⑥
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⑦
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⑧
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Type
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wavelength
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Grade
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Power Handling
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Axis Alignment
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Pigtail Diameter
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Fiber Length
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Connector
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S: Single stage
D: Dual stage
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64:1064nm
XX: Others
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P:P Grade
A: A Grade
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L: Refer to the above table
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B: Both axis working
F: Fast axis blocking
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25:250μm bare fiber
90:900μm Loose Fiber
XX: Others
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08:0.8m
10:1.0m
XX: Others
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00: None
FP: FC/PC
FA: FC/APC
XX: Others
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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-Displacer type polarization dependent isolator.
The structure and optical path of the Displacer optical isolator are shown in Figure 2, which consists of two collimators, two Displacer crystals, a half-wave plate, a Faraday rotator, and a magnetic ring. The forward light is incident on Displacer1 from collimator 1, and the unpolarized light is divided into o light and e light transmission. But this application is usually the transmission of linearly polarized light, and the direction of incidence of the collimator can be rotated to travel along the e-light path. After passing through the half-wave plate and the Faraday rotator and rotating counterclockwise, the conversion of o light and e light occurs. By flipping Displacer2, the e light (if any) is refracted out of the crystal from the side, and the o light is normally transmitted and coupled into the collimator 2 ; The reverse light is incident on Displacer2 from the collimator 2, and the o light is transmitted. After passing through the Faraday rotator and half-wave plate, it rotates counterclockwise, and there is no o-light and e-light conversion. At the transition after Displacer1, the beam are deviated from collimator 1 and isolated.
The disadvantage of the Displacer optical isolator is that in order to meet the isolation requirements, the two beams of light in the reverse optical path need to be shifted by a large distance, and the yttrium vanadate Displacer crystal with better birefringence , the ratio of the length to the offset can only be 10:1, which requires the Displacer crystal to be very large, resulting in a large device volume and high cost. But this kind of crystal usually has a higher Damage Threshold and is more suitable for using high power, such as 1030~1080nm TGG optical isolator.
Figure 2. Structure schematic diagram of displacer type polarization dependent isolator
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.