Bandpass filters selectively transmit part of the spectrum while cutting off all other wavelengths. Bandpass filters are well suited for a variety of applications, such as fluorescence microscopy, spectroscopy, clinical chemistry, or imaging. These band-pass filters are generally used in life science, industry or the R&D industry. The various bandpass filters provided by WDQ options have multiple bandwidth options. Laser line filters generally use a narrow bandwidth with a wavelength range of 2 – 5nm for narrow laser applications. Fluorescent filters generally use a wide band with a wavelength range of 20 – 70nm. This carefully designed product can maximize the energy of the excitation band and emission band.
The 10 nm filter introduced by WDQ options is suitable for chemical, environmental, or component analysis. Sputtered hard coated filter has high performance and durability. The traditional evaporated filter is a cost-sensitive choice. The traditional coated steam filter is a low-cost alternative. Bandpass filters are very angle-sensitive devices, so care should be taken when installing or integrating them into the optical system. A passband filter is a kind of filter, which can separate monochromatic light in a certain band. It has an asymmetrically distributed transmission curve, and the transmittance is the largest at the central wavelength. At half of the peak transmittance, the wavelength spacing △ of two symmetrical points on the transmittance curve λ Is the bandpass half-width of the filter.
It is divided into a narrowband filter and a wideband filter. It is used for spectral instruments to eliminate the overlap of grating spectral levels. We can customize band-pass filters with wavelengths ranging from 200nm to 1200nm, half bandwidth of more than 5nm, and cut-off depth of OD2 ~ od6. The products are widely used in laser, medical treatment, life science, security, and other fields. The band-pass filter can let the specified light wave pass through and cut off other interfering light. The band-pass filter adopts IAD ion-assisted coating technology to improve the density of the film and reduce the wavelength drift caused by changes in the external environment. It has the characteristics of high imaging quality and long service life, ensuring a wide cut-off range, high cut-off depth, and high light transmittance.
The main characteristic parameters of bandpass filter are:
① : center wavelength, also known as peak wavelength;
② : peak transmittance;
③ : half width, which is the wavelength width of the passband where the transmission peak is half of the peak;
④ : cutoff depth, minimum transmittance of suppression zone, i.e. background transmittance;
⑤ : long wave cut-off range;
⑥ : short wave cut-off range.
Application of broadband filter
In the practical application of optical engineering, not all places that need bandpass filters want the narrower the passband, the better, and some need broadband filters. For example, the automatic dimming mask for welding protection requires a band-pass filter that is transparent to visible light and cut off the depth of ultraviolet and infrared.
Application of narrowband filter
In addition to the characteristics of good thermal stability, low insertion loss and low polarization related loss, the ultra narrow band filter applied to optical fiber communication DWDM system must also have a rectangular passband in order to correctly extract each carrier from a beam of light containing multiple wavelengths at the transmission light terminal without crosstalk Smaller passband ripple and higher rejection ratio.
The 10 nm filter introduced by WDQ options is suitable for chemical, environmental, or component analysis. Sputtered hard coated filter has high performance and durability. The traditional evaporated filter is a cost-sensitive choice. The traditional coated steam filter is a low-cost alternative. Bandpass filters are very angle-sensitive devices, so care should be taken when installing or integrating them into the optical system. A passband filter is a kind of filter, which can separate monochromatic light in a certain band. It has an asymmetrically distributed transmission curve, and the transmittance is the largest at the central wavelength. At half of the peak transmittance, the wavelength spacing △ of two symmetrical points on the transmittance curve λ Is the bandpass half-width of the filter.
It is divided into a narrowband filter and a wideband filter. It is used for spectral instruments to eliminate the overlap of grating spectral levels. We can customize band-pass filters with wavelengths ranging from 200nm to 1200nm, half bandwidth of more than 5nm, and cut-off depth of OD2 ~ od6. The products are widely used in laser, medical treatment, life science, security, and other fields. The band-pass filter can let the specified light wave pass through and cut off other interfering light. The band-pass filter adopts IAD ion-assisted coating technology to improve the density of the film and reduce the wavelength drift caused by changes in the external environment. It has the characteristics of high imaging quality and long service life, ensuring a wide cut-off range, high cut-off depth, and high light transmittance.
The main characteristic parameters of bandpass filter are:
① : center wavelength, also known as peak wavelength;
② : peak transmittance;
③ : half width, which is the wavelength width of the passband where the transmission peak is half of the peak;
④ : cutoff depth, minimum transmittance of suppression zone, i.e. background transmittance;
⑤ : long wave cut-off range;
⑥ : short wave cut-off range.
Application of broadband filter
In the practical application of optical engineering, not all places that need bandpass filters want the narrower the passband, the better, and some need broadband filters. For example, the automatic dimming mask for welding protection requires a band-pass filter that is transparent to visible light and cut off the depth of ultraviolet and infrared.
Application of narrowband filter
In addition to the characteristics of good thermal stability, low insertion loss and low polarization related loss, the ultra narrow band filter applied to optical fiber communication DWDM system must also have a rectangular passband in order to correctly extract each carrier from a beam of light containing multiple wavelengths at the transmission light terminal without crosstalk Smaller passband ripple and higher rejection ratio.
Bandpass Filters
