Raman Spectroscopy

The Raman spectroscopy technique utilizes inelastic scattering of light incident on a gas, liquid or solid in order to determine its composition or structure. The challenge of Raman spectroscopy is the separation of the photons from the laser signal used to generate the Raman signal from the scattered photons providing the information.

Iridian's high performance Raman filters provide more signal with less background. They offer passband transmittances of > 90% and exceptional edge steepness and blocking of OD > 6, including:

• Edge Pass Filters
• Notch Filters
• Multiple Notch Filters
• Laser Line Filters

As with all Iridian filters, our Raman filters use hard dielectric coatings that do not require cover glass for durability. This greatly improves the filters' transmission levels, reliability and ease of handling in comparison to traditional filters. We use non-absorbing glass to provide blocking, reducing the chance of unwanted signals due to autofluorescence.

Standard & Custom Raman Filters

	Band Pass Filters Bandpass filters (BPF) are used to transmit one or more bands of wavelengths while blocking (or reflecting) adjacent wavelengths over extended ranges.
	Edge Pass Filters - Spectroscopy Optical edge pass filters (EPF) are needed to isolate transmitted wavelengths from blocked wavelengths often in a sharp transition.
	Laser Line Filters Iridian’s Laser Line (LL) Filters feature high transmittance in the passband and a steep roll-off.
	Multiple Band Pass Filters Iridian offers a full range of multiple band pass filters in the visible and near IR wavelength ranging from 400nm-2500nm.
	Multiple Notch Filters Iridian's Multi-Notch Filters incorporate the same benefits as our single notch filter with as many as 4 laser lines blocked in one filter.
	Notch Filters Applications such as Raman spectroscopy often require that certain frequencies within a narrow range be attenuated.