Linear variable edge filters can be used individually or in pairs to selectively block or transmit the target wavelengths. Linear variable edge filters are available in the form of long-wave-pass, short-wave-pass, or birefringent filters. Long-wave-pass edge filters transmit wavelengths longer than the starting wavelength, while short-wave-pass edge filters transmit wavelengths shorter than the cutoff wavelength.
The operation of birefringent edge filters is similar to that of long-wave-pass edge filters, but they can reflect unnecessary wavelengths. When used together, linear variable edge filters can be used as laser line filters or variable bandpass filters, and they have adjustable central wavelength and bandwidth.
Using in pairs can construct highly efficient custom bandpass filters.
The optimal input beam diameter is 0.2 x 8.0 mm.
OD3 Deadline
Also, there is a linear variable bandpass filter
Ultraopto’s Linear Variable Edge Filter is a high-performance tunable optical filter engineered with advanced gradient coating technology, featuring linearly shifting cut-on/cut-off wavelengths across the filter surface to enable flexible spectral range control for professional optical systems. As a specialized edge filter integrating the advantages of linear variable longpass and shortpass designs, our product delivers a tunable spectral range of 400-800nm for standard models, with customizable ranges across UV, visible and near-infrared bands, and a linear gradient rate that can be tailored to match specific application needs, providing precise and adjustable control over transmitted light wavelengths without replacing multiple fixed filters. Manufactured with high-vacuum ion beam sputtering coating technology on premium optical-grade glass substrates, our Linear Variable Edge Filter boasts steep spectral cut-on/cut-off edges, ensuring minimal spectral leakage and sharp transition between transmission and rejection bands, with an average peak transmittance of ≥85% in the target passband and an optical density of ≥3 in the rejection region, effectively blocking unwanted light and maximizing signal-to-noise ratio in optical detection systems.
We implement strict precision optical processing and coating quality control, achieving a superior surface quality rating of 60/40 scratch-dig and a clear aperture of over 90%, minimizing light scattering and reflection loss for optimal optical performance. The filter features a compact and robust structural design with standard sizes ranging from 30-60mm, and fully customizable dimensions, shapes and mounting options to fit diverse optical instrumentation and compact system integration needs such as portable spectrometers and miniature imaging devices. With excellent environmental stability, the scratch-resistant and durable hard coatings resist temperature changes, humidity and industrial field wear, ensuring long-term stable operation in both laboratory precision testing and harsh industrial field conditions, and maintaining consistent spectral performance even after frequent cleaning and use. Our Linear Variable Edge Filter is also designed with low chromatic aberration and uniform spectral response across the entire filter surface, avoiding signal distortion and ensuring high-fidelity spectral detection for quantitative analysis applications.
Ultraopto’s Linear Variable Edge Filter is widely applied in a broad range of professional optical fields that demand tunable spectral range control, including spectroscopy for isolating specific spectral lines or bands of interest to conduct detailed material and chemical composition analysis, and hyperspectral imaging for capturing multi-spectral images of biological samples and industrial materials to achieve precise material identification and surface defect detection. In fluorescence microscopy, it enhances the isolation of weak fluorescence signals by flexibly adjusting the cut-on/cut-off wavelength, improving imaging accuracy and contrast for biomedical research and clinical diagnosis. It also serves as a core component in various optical instrumentation such as spectral analysis equipment, environmental monitoring sensors and industrial inspection devices, providing precise wavelength control for stable and reliable optical performance. Additionally, the filter is an ideal choice for laser system beam cleanup and stray light reduction, as well as for academic research and optical experiment platforms that require flexible spectral manipulation.
As a leading manufacturer of precision linear variable optical filters, Ultraopto offers fully customized Linear Variable Edge Filter solutions to meet your unique spectral and application requirements. Our professional R&D and engineering team can tailor the tunable spectral range, linear gradient rate, cut-on/cut-off wavelength accuracy 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 anti-reflection coatings on the substrate back surface to eliminate ghost images and interference effects caused by back surface reflection, further enhancing optical transmittance efficiency.
All custom Linear Variable Edge Filter orders undergo multi-stage strict optical performance testing and quality inspection, including transmittance measurement, cut-on/cut-off wavelength linearity verification, optical density testing and environmental stability testing, with a detailed quality inspection report provided to ensure the final product fully complies with your design specifications and application needs. Backed by advanced gradient 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 Edge 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 Edge 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 optical systems.
