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783.5/23nm Band Pass Interference Filter
783.5/23nm Band Pass Interference Filter is designed to transmit light centered 783.5nm and FWHM 23nm. Coligh manufactures EUV to IR bandpass interference filter.
It has features below:
- Center wavelength 783.5nm
- FWHM 23nm
- Transmission above 90%
- Blocking depth OD>=6
- ION Assisted Hard Coating
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Near-Infrared 783.5/23nm Bandpass Interference Filter
783.5/23nm Band Pass Interference Filter Coligh manufactures is a high-precision optical filter based on multilayer thin film interference technology, designed for selectively transmitting narrowband spectra with 783.5nm as the center wavelength and 23nm bandwidth.
- Central wavelength 783.5+/-1nm, half bandwidth 23+/-1nm, high transmittance within 783.5+/-11.5nm range, extremely small error, and ultra-high batch consistency.
- The peak transmittance in the high-transmittance section is greater than or equal to 90%, which is suitable for single-photon technology and fluorescence imaging for weak light detection.
- The passband cutoff depth OD>=6 can effectively suppress stray light in other bands of ultraviolet, visible light and near-infrared.
- We use ion-assisted coating and hard coating technology to ensure the density, high adhesion and environmental corrosion resistance of the film layer.
- We use fused quartz as the substrate, other customized materials such as sapphire and silicon are optional, and flexible customization is supported in terms of size and shape.
783.5/23nm Band Pass Interference Filter Technical Datasheet
| Parameter | Specification |
| Center Wavelength (CWL) | 783.5nm ± 1 nm |
| Full Width at Half Maximum (FWHM) | 23nm± 1 nm |
| Peak Transmission | 90% |
| Blocking Range | 350-1000nm |
| Optical Density (OD) | OD ≥ 6 outside passband |
| Angle of Incidence (AOI) | 0° +/-5° |
| Surface Quality | 60/40 scratch-dig (per MIL-PRF-13830B) |
| Material Substrate | Fused Silica JGS1 |
| Coating Type | Hard-Coated Interference Filter/ IAD Assisted Coating |
| Thickness | 1mm (typical) |
| Filter Dimensions | Custom sizes available (e.g., Ø12.5 mm, 60×60 mm) |
| Clear Aperture | >90% of physical size |
| Operating Temperature | -40°C to +85°C |
783.5/23nm Band Pass Interference Filter Applications
- Raman spectroscopy detection
In the rapid screening of pesticide residues, organophosphorus pesticides show characteristic peaks at 783.5nm Raman shift, which needs to replace laboratory chromatographic analysis. The 783.5/23nm optical filter can be embedded in a handheld Raman detector to screen the 783.5nm scattered signal and match the pesticide spectrum database. Enhance the intensity of characteristic peaks and suppress the background noise of food matrix. - Military laser communication
The 783.5nm laser has low atmospheric transmission loss and is far away from common interference bands, which is suitable for confidential communication. This filter can be embedded in the laser communication receiving end to filter out non-783.5nm stray light and improve the signal-to-noise ratio. Suppress enemy electronic interference and natural light background noise. - Astronomical research
Interstellar dust scatters starlight at 783.5nm, and the background continuous spectrum interference of the Milky Way needs to be suppressed. This filter can be carried at the entrance of the infrared telescope spectrometer to extract the target scattered signal. Improve the signal-to-noise ratio of weak signals and reduce the complexity of data processing. It helps to discover the distribution law of dust in star formation regions and promote the study of cosmic evolution models. - Endoscopic imaging
The absorption rate of tumor tissue in the 783.5nm near-infrared window is significantly higher than that of normal tissue. This filter can be integrated into the endoscopic imaging system to enhance the contrast of the lesion area, suppress the interference of mucosal surface reflection, and highlight the absorption difference of deep tissue. Real-time display of tumor boundaries.
