Applications such as gas sensing using nondispersive infrared (NDIR) sensors require an IR source to pass through a gas onto an IR detector. Any absorption by the gas at specific wavelengths indicates a certain concentration of that gas. Wavelengths are selected using narrow band pass (NBP) optical filters placed within the optical path, but often placed within the detector envelope. Popular IR gas absorbing wavelengths are 3.4 µm (methane), 4.26 µm (CO2), 4.66 µm (CO), 7.3 µm (SO2), and more, found on our website.
Helioworks based in Santa Rosa California USA manufacture both steady state and pulsable IR emitters, with a choice of windows such as sapphire, calcium fluoride and zinc selenide, or no window, to suit the spectral design of the sensor, and housed in TO-5, TO-8 or TO-3 packages. Filaments include tungsten, NiCr, and Kanthal. Custom configurations are possible.
Key features include long term stability, desirable signal to noise ratio, larger temperature modulation in pulsed mode, and the use of latest technology in packaging and window design.
