The Gentec-EO Hybrid Terahertz Pyroelectric Detector can be fitted with a permanent IR window to narrow the wavelength range. The S5/8 option has a range of 0.3 – 4.5 and 100 - 1000 μm, the Q5/8 option has a range of 0.25 – 3.0 and 50 - 1000 μm, and the Si5/8 option has a range of 1.2 – 8.0 and 50 - 1000 μm.