Conventional spectrometer measurement technology reaches its noise limit at an attenuation of OD5 (i.e., at an attenuation factor of 100,000). In special Raman applications and protective filters for doctors, much higher attenuation levels are required. Using modern production methods, such filters can be manufactured; however, it is necessary to test their quality. Even such defects as nano-pinholes can lead to missing the targeted specifications. Our partner Omega Optical recently developed a measurement station that, in addition to the conventional spectrophotometer, can measure the attenuation up to OD8 (i.e., an attenuation factor of 100,000,000) as well.
This technology was introduced for the first time at Photonics West 2013. The presentation “Measuring Sharp Spectral Edges to High Optical Density” is available on the SPIE website.
