PolaZero DEP Series Passive Fiber Optic Depolarizer
Passive fiber optic depolarizers that reduce the output degree of polarization of a light source to below 5%.
- Center wavelength
- 1310 or 1550 nm standard, others available
- Operating wavelength range
- ±50 nm
- Output DOP
- <5%
- Coherence length of light source
- 0 to 30 mm
Overview
The DEP series are passive fiber optic depolarizers that reduce the degree of polarization (DOP) of a light source to an output DOP below 5%. The standard configuration is intended for light sources with coherence lengths less than 10 meters. Custom versions can be built for specific light sources, including lasers with coherence lengths in the kilometer range, which are supplied in a larger package.
Operating principle
A depolarizer introduces a differential delay between the orthogonal polarization components of the light. When this delay is longer than the coherence length of the source, the phase relationship between the two polarization components is removed. Different internal structures are used depending on the requirements of the application, so the internal structure and package size can vary with the coherence length or spectral width of the signal to be depolarized.
Models
The DEP-002 is intended for broadband sources with short coherence lengths, and the DEP-003 for narrowband sources. The device is passive and requires no power source.
Typical uses include reducing the polarization sensitivity of fiber sensor systems, such as FBG-based sensing and distributed sensing based on Brillouin, Raman or Rayleigh scattering. It is also used to reduce the effects of PDL or polarization sensitivity in optical components and instruments, and to depolarize pump lasers for Raman amplifiers.
Models in this series
| Model | Description | |
|---|---|---|
| DEP-002 |
PolaZero DEP-002 Passive Fiber Optic Depolarizer for Broadband Light Sources
Passive fiber optic depolarizer for broadband light sources with coherence lengths of 0 to 30 mm, producing an output DOP below 5%. |
Details → |
| DEP-003 |
PolaZero DEP-003 Fiber Optic Depolarizer for Narrowband Sources
Passive fiber optic depolarizer for narrowband light sources with coherence lengths up to 300 m, delivering output DOP below 5%. |
Details → |
Key Features
- Low output DOP <5%
- Customizable for different wavelengths and coherence lengths
- Passive device, no power source required
- Low insertion loss
- Compact size
- For lasers with coherence length up to and beyond 10 m
- Wide operating wavelength range
Specifications
| Center wavelength | 1310 or 1550 nm standard, others available |
|---|---|
| Operating wavelength range | ±50 nm |
| Output DOP | <5% |
|
Coherence length of light source
DEP-002 |
0 to 30 mm
For broadband sources |
|
Coherence length of light source
DEP-003 |
0 to 300 m
For narrowband sources |
| Insertion loss |
<1.4 dB (1.0 dB typical)
Excluding connectors; for DEP-003 with 10 m coherence length |
| Residual extinction ratio | < 0.5 dB |
| Return loss |
55 dB
For DEP-003 with 10 m coherence length; values referenced without connectors |
| Optical power handling | 300 mW min. |
|
Fiber type
DEP-003 |
Input: PM Panda fiber, Output: SM
For DEP-003 |
|---|---|
|
Fiber type
DEP-002 |
Typically all PM fiber, designed to connect to SM fiber on both input and output sides
Can be built for an SM output light source; specify when ordering |
| Storage temperature | -40 to 85 °C |
|---|
|
Dimensions
DEP-003 |
85 × 85 × 15 mm |
|---|---|
|
Dimensions
DEP-002 |
85 × 60 × 10 mm or 85 × 85 × 15 mm
Depending on the coherence length of the light source |
Applications
- Fiber sensor systems
- Communication systems
- OEM modules for fiber optic sensing
- FBG-based fiber sensor systems
- Brillouin, Raman or Rayleigh scattering based distributed fiber sensor systems
- Raman amplifiers
- Optical instruments
- Optical components with PDL
Options & Accessories
| Option | Description |
|---|---|
| 15 | Wavelength: 1550 nm |
| 13 | Wavelength: 1310 nm |
| 10 | Coherence length: 10 m — Other coherence lengths on request |
| FC/PC | Connector type: FC/PC |
| FC/APC | Connector type: FC/APC |
| NC | No connectors |