

632.8nm Laser Cleanup Filter
The 632.8nm laser cleanup filter is an optical filter specially designed for He-Ne lasers and red laser diodes (LDs). Coligh manufactures a variety of high performance laser line cleanup filter.
632.8nm laser cleanup filter Coligh manufactures has the features below:
- High transmission around 95% for 632.8nm laser
- Deep blocking depth OD>6, which can ensure accurate detection of Raman scattering spectrum
- Steepness <1.2nm transition period can reduce background noise and improve the contrast of Raman signal
- Using hard coating interference technology
632.8nm Laser Line Cleanup Filter Descriptiom
The 632.8nm laser cleanup filter produced by Coligh is specially designed for He-Ne lasers and red laser diodes (LD). Its main function is to transmit a single laser wavelength of 632.8nm, improve laser output efficiency, increase the excitation intensity of Raman signals, and block other stray light and non-essential wavelengths such as Rayleigh scattering and fluorescence interference, reduce background noise, and improve signal-to-noise ratio. The core technical capabilities of this filter are:
- Specially optimized for 632.8nm lasers, the transmittance of the target wavelength is >95%, which can avoid signal contamination
- We use a multi-layer hard film process, which can suppress fluorescence interference and stray light by >99%, which can improve the detection ability of weak signals
- The steep filtering boundary (such as the 1.2nm transition band) means that the filter can switch from high transmission to high blocking within a very narrow wavelength range. Many lasers will generate spontaneous radiation.
- The steep transition band can accurately filter out the stray light of the target wavelength and reduce background interference. At the same time, it can ensure that the 632.8nm laser can have a highly pure single-wavelength output, improving the contrast of the Raman spectrum
632.8nm Laser Line Cleanup Filter Spectrum Performance

632.8nm Laser Cleanup Filter Technical Datasheet
Center wavelength: | 632.8nm | Coating | Hard-coated |
Full Bandwidth half maximum | 2nm | Angle of Incidence | 0 +/-2 deg |
Transmission Peak | Average>93% | Size avaliable | Dia12.5nnm Dia 25mm, or custom |
Optical Density | OD>6 | Substrate thickness | 1.0mm unmounted |
Clear Aperture | >80% of diameter | Mounted Option | Mounted in Black Anodized Ring |
Surface quality | 60-40 | Mounted thickness | 3.5+/-0.1mm |
Environmental and Physical Durability | MIL-STD-810F, MIL-C-48497A |
632.8nm Laser Line Cleanup Filter Applications
632nm laser line cleanup filters play an important role in Raman, and have the following main applications:
- Raman spectroscopy 632.8nm He-Ne laser is a common Raman excitation light source, which can significantly improve the signal-to-noise ratio of Raman signals and is widely used to detect proteins, DNA and cell tissues to ensure signal clarity and improve data reliability
- In optical measurement systems such as Michelson interferometers and Fabry-Perot interferometers, 632.8nm lasers are often used for high-precision measurements to ensure the contrast and clarity of interference fringes
- In material characterization, chemical reaction monitoring and pollutant detection, 632nm laser line filters can optimize Raman spectroscopy analysis and ensure experimental accuracy
- 632.8nm laser line cleanup filters can also be used for environmental monitoring to detect harmful substances in environmental samples