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1555nm Transmit 1540nm Reflect Narrow Band Splitter
1555nm Transmit 1540nm Reflect Narrow Band Splitter is an laser beamsplitter to high transmit at 1550nm and reflect at 1540nm. Coligh manufactures high performance laser beamsplitter.
- AOI: 22.5°
- R>=96%@1540nm
- T>=96%@1555nm
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1555nm Transmit 1540nm Reflect Narrow Band Splitter Description
1555nm Transmit 1540nm Reflect Narrow Band Splitter is a high-precision multilayer dielectric film laser beam splitter designed for efficient separation of near-infrared dual-wavelength lasers (1555nm transmission, 1540nm reflection).
- We use ion-assisted coating technology and precise film design to balance the dual-wavelength splitting efficiency. Reflection at 1540nm>=96%, transmission at 1555nm>=96%,
- This filter supports incident angle changes of 0 and 22.5 degrees.
- In addition, we use substrate fused quartz to strictly match the thermal expansion coefficient of the film layer to ensure zero drift due to temperature changes.
1555nm Transmit 1540nm Reflect Dual Wavelength Laser Beamsplitter Datasheet
| Parameter | Specification |
| Center Wavelength | 1540nm (Reflection) / 1555nm (Transmission) |
| Reflection @1540nm | >96% |
| Transmission @1555nm | >96% |
| Angle of Incidence (AOI) | 0°22.5° |
| Surface Quality | 60-40， 40-20 (MIL-PRF-13830B standard) |
| Coating Technology | High reflection (HR) & high transmission (HT) coating |
| Substrate Material | Fused silica |
1555nm Transmit 1540nm Reflect Narrow Band Splitter Applications
1555nm Transmit 1540nm Reflect Dual Wavelength Laser Beamsplitter is mainly used in the following application scenarios:
- Distributed fiber sensing system (DTS/DAS)
In oil and gas pipeline temperature monitoring and power cable health monitoring, this filter can separate pump light from signal light, reflect 1540nm Raman pump light to excite scattering effects in optical fiber, and transmit 1555nm Stokes/anti-Stokes signal light for temperature or strain analysis, which can monitor pipeline leakage or cable overheating in real time - LiDAR and autonomous driving
In applications such as vehicle-mounted LiDAR, drone obstacle avoidance, and terrain mapping, this filter can reflect 1540nm laser for short-distance high-resolution imaging (such as pedestrian recognition) and transmit 1555nm laser for long-distance obstacle detection (such as vehicles 200 meters away). The 1555nm wavelength has a stronger ability to penetrate rain and fog, which can reduce the misjudgment rate in bad weather. - Medical laser treatment
In medical laser treatments such as skin disease treatment (vascular closure), ophthalmic surgery, endoscopic OCT, etc., this filter can synchronize treatment and imaging, reflect 1540nm laser to accurately act on blood vessels or diseased tissues, and transmit 1555nm light for real-time OCT imaging to monitor treatment depth. - Industrial laser processing
In precision welding and 3D printing, this filter can reflect 1540nm high-energy laser for welding/cutting, and transmit 1555nm coaxial light for high-speed photography.
