SureBlock™ Ultra Narrow-band Notch Filters

Coherent’s SureBlock Ultra Narrow-band Notch Filters are the ideal solution for highly selective wavelength applications like low frequency (low wavenumber) THz-Raman^® spectroscopy.

With laser line attenuation of up to 99.9999% (optical density: OD4) and transition width of <10 cm^-1, SureBlock filters can dramatically improve the ability of any Raman system to resolve low frequency Raman scattering. High transmittance on both sides of the notch enables both Stokes and anti-Stokes Raman spectra to be observed simultaneously.

Individual filters are mounted in 1” housings for compatibility with standard 1” optical systems. Alternatively, our SureBlock XLF Series THz-Raman Spectroscopy and Filter Systems integrate the notch filters into a rugged, pre-aligned, light-tight enclosures with optional laser sources, ASE filtering, and free space or fiber inputs and outputs.

Available at standard Raman wavelengths: 488, 514, 532, 633, 785, 808, 830, 976 and 1064 nm. Custom wavelengths are available on demand. We also recommend the use of our NoiseBlock™ ASE Filters and 90/10 Beamsplitter Filters to achieve optimum performance of the notch filters when using diode or diode-pumped laser sources SureBlock Notch filters are reflective volume holographic filters (VHGs), produced in a proprietary glass designed for long lifetime, high efficiency, and excellent transmission. Coherent’s fabrication process is highly stabilized to ensure excellent part-to-part repeatability.