Long Wave Pass
Overview
Long Wave Pass filters (also referred to as edge filters) are constructed from stacks of thin layers. They are distinguished by a sharp transition from a zone of rejection to a zone of transmission. The rejection region extends to below 0.3um and the transmission region typically extends to greater than twice the wavelength of the edge position. When ordering it is necessary to specify the required 5% or 50% cut on edge position (the 5% point is measured as an absolute value but the 50% point is measured as 50% of peak transmittance).
Typical Characteristics
| Available wavelength range <span class="italic">(edge position)</span> | ~1.2 to 20 µm |
| Edge tolerance | To customers requirements, from ±1% but standard tolerance ±4% |
| Average transmittance | Typically >75% (depending on wavelength) |
| Cut on slope | Typically < 5% |
| Blocking (attenuation) | Typically <0.1% down to 0.3 µm |
Typical Performance
