Skip to content 
5000nm (5.0μm) Infrared Shortpass Filter
5000nm (5.0μm) Infrared Shortpass Filter is designed to transmit infrared light below 5000nm and blocking longer wavelength. Coligh manufactures IR shortpass filter.
It has key features below:
- Cut off wavelength 5000nm (5.0μm)
- >=90% high transmission
- Blocking Tave<1%
- IR-grade silicon substrate
- Dielectric hard coating
Products Categories
Get A Free Quote
5.0μm Cutoff Infrared Optical Filter Description
The 5000nm Infrared Shortpass Filter (SPF) is a precision optical component designed to selectively transmit light with wavelengths ≤5000nm (from visible to near/mid-infrared) while effectively blocking long-wave infrared radiation >5000nm.
- It achieves high-precision cutoff at 5000nm ±100nm, ensuring high transmission in the target band and strong blocking of interfering wavelengths.
- With a transmittance ≥90% in the 3700–4900nm range, it maximizes the retention of effective signals.
- For infrared radiation above 5250nm, it maintains a blocking depth of T<1% in the 5250–10000nm range, effectively suppressing thermal noise.
- We use ion-assisted deposition (IAD) to apply a multi-layer hard coating that is scratch-resistant and corrosion-resistant.
- The substrate is silicon, which has a high thermal expansion coefficient and exhibits less wavelength drift at high temperatures.
5000nm (5.0μm) Infrared Shortpass Filter Technical Datasheet
| Parameter | Specification |
| Cut‑off Wavelength (50% T) | 5000nm+/-100nm |
| High‑Transmission Band | ≥ 90% @ 3700-4900nm |
| Blocking Region | 5250-10000nm |
| Optical Density (OD) | OD >2 (T < 1%) |
| Substrate Materials | Silicon, White glass |
| Coating Type | Hard first‑surface all‑dielectric |
| Surface Quality | 80-50, 60‑40, 40-20 scratch‑dig (MIL‑PRF‑13830B) |
| Clear Aperture | ≥ 90% of full aperture |
| Available Diameters | Ø25 mm, Ø55mm, or custom |
| Thickness | 0.5mm or 2.5mm or custom |
5000nm (5.0μm) Infrared Shortpass Filter Applications
- Real-Time Monitoring of Workpieces in High-Temperature Industrial Furnaces
In furnaces with temperatures exceeding 800 °C, background thermal radiation peaks beyond 5 μm can overwhelm the 3–5 μm thermal signals from microcracks on workpieces, leading to missed detections. A 5000nm shortpass filter integrated in front of the thermal imager can transmit defect-related infrared radiation while blocking >5 μm furnace noise, significantly improving defect detection rates. - CO₂ Laser Processing
Reflected 10.6 μm CO₂ laser light can burn CCD sensors, and traditional neutral density filters cannot effectively separate laser radiation from 500 nm visible positioning beams. A 5000nm infrared shortpass filter can block 10.6 μm laser light, extending the service life of CCD detectors. - Methane Gas Leak Detection
Methane (CH₄) exhibits strong absorption at 3.3 μm, but background thermal radiation above 5 μm can cause baseline drift in NDIR sensors. A 5000nm shortpass filter allows precise transmission of the 3.2–3.4 μm CH₄ absorption band while blocking >5 μm radiation, reducing false positives. - UAV-Based Forest Fire Surveillance
CO₂ flame emission peaks around 4.4 μm, but sun-heated surfaces can produce false fire signals. A silicon-based 5000nm shortpass filter mounted in front of a SWIR camera transmits the 4.2–4.6 μm flame signature while blocking >5 μm ground radiation, improving fire spot recognition distance.
