Bandpass or Longpass Colored Glass Filters

Optical filters selectively transmit light in a specific range of wavelengths, while blocking the remaining wavelengths. Filters can be broad transmitting large wavelength ranges or very specific & targeted only to a few wavelengths. Bandpass Filters transmit a band of wavelengths while blocking the wavelengths on either side of that band. The opposite of a bandpass filter is a notch filter which blocks a specific band of wavelengths. Longpass filters transmit wavelengths longer than the specified cut-on wavelengths and block the shorter wavelengths. Shortpass filters are opposite and transmit the shorter wavelengths. Optical glass filters are widely used in safety glasses, industrial measurement, regulation technology and environment protection.

Due to its selective absorption in visible wavelength range, colored glass filter exhibits various color depending the glass type. Colored glass filters are used to selectively transmit certain wavelength ranges and block others or to reduce the amount of heat transmitted through the system. They are categorized into longpass filters, shortpass filters, bandpass filters, heat absorbing and neutral density filters. Colored glass filters provide an economical filter for various applications.

Paralight Optics offers colored glass filters fabricated from different types of Schott® glass: longpass filters including ultra-violet (WG280, WG295, WG305, WG320), golden Yellow color (GG395, GG400, GG420, GG435, GG455, GG475, GG495), orange color (OG515, OG530, OG550, OG570, OG590), red color (RG610, RG630, RG645, RG665, RG695, RG715) and black color (RG780, RG830, RG850); bandpass filters including UV transmitting & VIS absorbing (UG1, UG5, UG11), green color (VG9), blue color (BG3, BG7, BG18, BG25, BG36, BG38, BG39, BG40); neutral density filters (neutral glass with uniform attenuation in the visible range): NG1, NG3, NG4, NG5, NG9, NG11; Heating Absorbing (Colorless glass with high transmission in the visible and absorption in the IR range): KG1, KG2, KG3, KG5. These colored glass filters are available in both round and square shapes, either uncoated or specifying your coating. Please check the following graphs for bandpass colored glass filters with a broadband antireflective coating designed for either the 245 – 400 nm or 350 – 700 nm wavelength range, which is deposited on both surfaces of a Schott® glass substrate that has been selected for its high transmission in the ultraviolet or visible.