What types are classified according to spectral filters?

From the length of the spectrum (region): ultraviolet light, visible light, near-infrared light, infrared light, far-infrared filter.

Common names: 180nm-400nm ultraviolet light, 400nm-700nm visible light; ， 700nm-3000nm infrared light, spectra above 3000nm-10um are far-infrared (already beyond the band produced by our company). Filter products are mainly classified according to spectral bands, spectral characteristics, film materials, application features, and other methods.

Spectral bands: UV filter (180-400nm), visible light filter (400-700nm), infrared filter (700-3000nm)

Spectral characteristics: bandpass filter, cutoff filter, spectral filter, neutral density filter, reflective filter, notch filter (negative filter)

Film layer materials: soft film filter, hard film filter (hard film filter not only refers to the hardness of the thin film, but more importantly, its laser damage threshold, so it is widely used in laser systems, while soft film filter is mainly used in biochemical analyzers.

Bandpass type: The selected wavelength band of light passes through, and the light in the passband is cut off. Its optical index is mainly the center wavelength (CWL), and the half width at half maximum (FWHM) is divided into narrowband and wideband. For example, the 808 filter NBF-808.

Short wave pass type (also known as low-pass): Light shorter than the selected wavelength passes through, and light longer than that wavelength is cut off. For example, an infrared cut-off filter, IB-650.

Long wave pass type (also known as high wave pass): Light longer than the selected wavelength passes through, while light shorter than that wavelength is cut off. For example, the infrared transmission filter IP-800

Classification of the following spectrograms (for reference only):

1) Spectral curve of bandpass filter:

2) Long wave pass spectrum curve:

3) Short wave spectral curve:

For more details, please follow the company's product details.