Bandpass Filters
Bandpass Filters
A bandpass filter is an optical filter designed to transmit a defined range of wavelengths while blocking wavelengths outside the passband. Bandpass filters are widely used in optical systems where spectral isolation, signal separation, or background suppression is required. Typical applications include fluorescence detection, spectroscopy, machine vision, laser systems, and analytical instrumentation.
At Star Optics, bandpass filters are produced using thin-film interference coating technology, allowing precise control of spectral characteristics such as center wavelength, bandwidth, and blocking performance. Filters are available in standard configurations as well as custom designs optimized for specific system requirements
Types of Optical Bandpass Filters
Optical bandpass filters can be classified based on coating structure and intended application. At Star Optics, optical bandpass filters of the following types are available, either as standard designs or produced to meet specific application requirements.
All-Dielectric Bandpass Filters
All-dielectric bandpass filters are constructed using alternating layers of high- and low-refractive-index dielectric materials. This type of bandpass filter is available for visible and near-infrared wavelength ranges where stable spectral performance is required.
Metal-Dielectric Bandpass Filters
Metal-dielectric bandpass filters incorporate metallic layers within the coating stack. This design approach is available for ultraviolet bandpass filter applications where dielectric-only designs may be limited by material absorption or coating thickness constraints.
Narrowband Bandpass Filters
Narrowband bandpass filters are available for applications requiring transmission over a limited spectral range with controlled blocking outside the passband. Typical uses include laser line isolation, fluorescence excitation and emission separation, and optical signal clean-up.
Multiband Filters
Multiband filters with multiple passbands in a single optical element are available for applications requiring the transmission of more than one wavelength range. These filters are generally implemented as application-specific coating designs.
Custom Optical Bandpass Filters
Standard bandpass filters are available for common wavelength ranges and bandwidths. However, many optical systems require customized spectral performance, including specific center wavelengths, bandwidths, blocking levels, angles of incidence, or substrate sizes.
Star-Optics offers custom optical bandpass filter solutions tailored to application-specific requirements. By working closely with system designers, filters can be optimized to achieve the desired balance between transmission, blocking, and overall system performance.
For additional information on standard offerings or to discuss custom bandpass filter requirements, please contact us.
