The Spectral Systems Standard Long Wave Pass Filters provide a sharp cutoff below a particular wavelength. Often used for optimizing the infrared spectral analysis region, they isolate broad regions of the spectrum, simultaneously providing high transmission of desired energy and deep rejection of unwanted energy. Constructed of hard, durable first-surface dielectric coatings on optical-quality IR-transmitting substrates, these filters will withstand normal cleaning and handling associated with any high-quality optical component. For your sampling design requirements, we offer the filters in three standard sizes: 12.5, 25 mm and 50 mm diameter. Long Wave Pass Filters are designed to transmit wavelengths greater than the cut-on wavelength of the filter. Long Wave Pass Filters are used to isolate portions of the spectrum in a variety of industrial or life sciences applications including microscopy or fluorescence instrumentation. Certain Long Wave Pass Filters can also be used as cold mirrors to minimize the heat buildup often caused by infrared radiation. Please contact us for other requirements