Dichroic Filter coatings are designed to transmit one spectral region (passband) and reflect another (rejection band).
The filter is a Short Wave Pass (SWP) if the passband is to the left of the transition slope, and a Long Wave Pass (LWP) if the passband is to the right of the slope.
The advantages of Dichroic Filters over Colored Glass Filters are:
The rejection band is reflected rather than absorbed.
Steeper transition slope between the passband and the rejection band; i.e. sharper cut-on or cut-off.
Coatings can be custom designed for specific center wavelengths.
Dichroic Filter coatings are designed to transmit one spectral region (passband) and reflect another (rejection band).
The filter is a Short Wave Pass (SWP) if the passband is to the left of the transition slope, and a Long Wave Pass (LWP) if the passband is to the right of the slope.
The advantages of Dichroic Filters over Colored Glass Filters are:
- The rejection band is reflected rather than absorbed.
- Steeper transition slope between the passband and the rejection band; i.e. sharper cut-on or cut-off.
- Coatings can be custom designed for specific center wavelengths.
