Short- and Long-pass Filters (Quasar Technology)

A Short Pass or Short Wave Pass filter ("SP”) is a filter that transmits at shorter wavelengths and rejects longer wavelengths. By contrast, a Long Pass or Long Wave Pass filter ("LP”) is one that transmits at longer wavelengths and rejects shorter wavelengths.

 

By using proprietary 'Quasar' technology, the transition in both SP and LP filters between the 50% cut-off or cut-on to rejection is quite sharp. This makes it much easier to separate excitation from emitted wavelengths without interfering with wavelengths of interest. SP and LP filters are useful in applications where spectral noise reduction is important or for isolating a particular region of the spectrum. They can be used as emission filters in fluorescence applications, to eliminate any unwanted radiation, in Raman spectroscopy, as order sorting filters, as well as in astronomical applications. They are also used in laser-induced fluorescence to isolate source radiation.