Optical bandpass filters are designed to transmit a specific waveband.  They are composed of many thin layers of dielectric materials, which have differing refractive indices to produce constructive and destructive interference in the transmitted light

RF filters and microwave filters are devices that pass or reject signals by frequency. Basic types include bandpass filters, band reject filters, low pass filters, and high pass filters

Signal filters block or decrease (attenuate) unwanted frequencies or signal wave characteristics

Active filters are electronic filers that use active components such as voltage amplifiers or operational amplifiers. The amplifier shapes and stabilizes the behavior of the filter, and serves as a buffer interface to the driven component

Active band pass filters are used to attenuate frequencies below and above a range of frequencies (i.e., the bandwidth or passband of the filter

Camera filters provide a range of optical filtering effects in scientific, research, and industrial applications

Passive filters are implemented using only passive components such as resistors, capacitors and inductors. These filters do not produce any amplification of the input signal

Digital filters use digital signal processing (DSP) to perform numerical calculations on sampled values of a signal

IC electronic filters are frequency-selective circuits that consist of devices such resistors, capacitors, inductors, transistors, or operational amplifiers coupled with reactive components

Long pass filters transmit a wide spectral band of long wavelength radiation while blocking short wavelength radiation. Short pass filters transmit a wide spectral band of short wavelength radiation and block long wave radiation

Fiber optic filters allow only specific wavelengths to pass into a larger fiber optic system

RF high pass filters pass signals from high frequencies and reject signals from low frequencies

Color filters include a wide range of filter types that are distinguished by their specific color spectrums and wavelengths, as well as their Schott glass compositions

RF band reject filters are tuned circuits that prevent the passage of signals within a specified band of frequencies. These devices are also known as bandstop or notch filters

RF band pass filters are active or passive circuits that pass signals from a specific frequency band and reject signals from out-of-band frequencies. Surface acoustic wave (SAW) filters, crystal filters, and cavity filters are types of band pass filters