A linear variable bandpass filter is an accurately coated filter whose spectral properties change linearly with the variation of the filter's length. Linear variable bandpass filters have high transmittance within a narrow bandwidth and can deeply cutoff unnecessary light sources, thereby maximizing system performance within the desired wavelength range. Users can adjust the spectral response simply by moving the filter to change its orientation relative to the light source.
Additionally, a single linear variable bandpass filter can replace multiple dedicated filters, simplifying system setup and minimizing the overall weight of the system.
Narrow bandwidth, high transmission rate The optimal input beam diameter is 0.5 x 10.0 mm. OD4 deadline
An adjustable linear edge filter is also provided.
Ultraopto’s Linear Variable Bandpass Filter (LVBF) is a high-performance tunable optical filter engineered with advanced wedge-shaped multi-layer coating technology, featuring a continuously varying center wavelength across the filter surface to replace multiple traditional fixed-wavelength bandpass filters, serving as a core component in spectroscopy, hyperspectral imaging, fluorescence microscopy and portable spectral analysis equipment. Crafted from premium optical-grade glass substrates with precision wedge-shaped multi-layer dielectric coatings, our LVBFs deliver a broad tunable spectral range (450nm-1000nm for standard models, custom ranges available from UV to IR), with a linear gradient rate of up to 60nm/mm and precise center wavelength control to enable continuous wavelength tuning by simply sliding or rotating the filter. The filters feature a high spectral resolution with a full-width at half-maximum (FWHM) of 50nm-400nm, and a peak transmittance of ≥60% in the passband, ensuring high-fidelity spectral detection and measurement across the entire tunable range.
Manufactured with ultra-precise wedge coating technology and precision optical processing, our Linear Variable Bandpass Filters achieve superior surface quality with an 80-50 scratch-dig rating and a clear aperture of over 90%, with the wedge-shaped coating design ensuring uniform spectral performance and low optical loss across the filter surface. The out-of-band rejection region features an optical density (OD) of ≥3, efficiently blocking unwanted light and maximizing the signal-to-noise ratio in spectral detection systems, with sharp transition edges between the passband and rejection band to enhance spectral selectivity. We offer standard filter sizes (30mm-40mm) and fully custom dimensions, including compact designs for portable spectral analysis equipment and large-aperture designs for hyperspectral imaging systems, with customizable FWHM, gradient rate and spectral range to match specific application requirements.
The filters feature a compact and lightweight design, ideal for integration into portable, battery-powered and space-constrained optical setups, with durable coatings that exhibit excellent environmental stability and mechanical durability, ensuring long-term stable operation in both laboratory and field conditions.
Our Linear Variable Bandpass Filters are a versatile and cost-effective optical solution for a broad range of professional spectral analysis fields, including spectroscopy for isolating specific spectral bands and conducting detailed spectral analysis of materials, chemicals and biological samples without the need for multiple fixed-wavelength filters. In hyperspectral imaging, the filters enable the capture of high-resolution spectral images for precise material identification, environmental monitoring and biomedical imaging, while in fluorescence microscopy, they provide tunable excitation/emission wavelength selection for high-contrast imaging of biological samples. They are also essential in portable spectral analysis equipment for on-site environmental monitoring, industrial quality control and food safety testing, in laser systems for tunable wavelength selection and beam shaping, and in aerospace and remote sensing systems for high-resolution spectral detection and measurement of the Earth’s surface and atmosphere.
As a leading manufacturer of tunable optical filters, Ultraopto offers fully customized Linear Variable Bandpass Filter solutions to meet your unique spectral and application requirements. Our professional R&D and engineering team can tailor tunable spectral ranges, FWHM, gradient rates, substrate materials (optical glass, fused silica) and filter dimensions, with ultra-strict tolerance control for high-precision optical systems such as scientific research spectroscopy and hyperspectral imaging systems. We also provide custom coating designs for ultra-narrow FWHM, ultra-deep out-of-band rejection or ultra-broad tunable ranges, and anti-reflection coatings to further reduce surface reflection loss and enhance optical performance.
All custom LVBF orders undergo multi-stage strict optical performance testing and quality inspection, including transmittance measurement, center wavelength linearity verification, FWHM testing and out-of-band rejection measurement, with a detailed quality inspection report provided to ensure the final product fully complies with your design specifications and application needs. Backed by advanced wedge-shaped multi-layer coating technology, rich experience in tunable filter design and a complete quality control system, Ultraopto ensures stable batch supply capacity and consistent product quality, providing global customers with high-quality Linear Variable Bandpass Filter products and one-stop tunable optical filter solutions. For more detailed technical parameters, product quotation information or custom design solutions for our Ultraopto Linear Variable Bandpass Filter, please contact our professional sales and technical team through the official website, and we will provide you with efficient, personalized and professional optical solutions to support the development and optimization of your high-precision spectral analysis systems.
