Custom Optical Filters | Precision Filters for Advanced Optical Systems
Avantier designs and manufactures custom optical filters engineered for high-precision imaging, laser-based systems, spectroscopy, biomedical instruments, aerospace platforms, semiconductor inspection, and advanced R&D environments.
Our filters deliver exceptional performance across visible, UV, and IR wavelengths — providing high transmission efficiency, steep spectral edges, deep blocking (up to OD6), thermal stability, and low wavefront distortion.
As a trusted supplier to engineering teams, laboratories, OEM system manufacturers, and scientific institutions, Avantier supports both prototype development and high-volume production.
Core Optical Filter Capabilities
- Hard-coated interference filters & dielectric coatings
- Dichroic, bandpass, longpass, shortpass, notch, and Raman filter engineering
- Custom spectral wavelengths, slopes, and bandwidths (ultra-narrowband available)
- Precision polishing & optical glass solutions
- High laser damage threshold coatings
- Custom mechanical mounting & filter assemblies
Explore Our Custom Filter Portfolio
Cost-efficient OD4 notch filters for laser rejection applications requiring high transmission outside the stopband. Engineered for system stability and precise wavelength blocking.
Suitable for laser-based instruments, fluorescence systems, machine vision, and Raman spectroscopy.
Advanced OD6 notch filters delivering 1,000,000× attenuation with exceptional out-of-band transmission (93% typical). Ideal for critical scientific and semiconductor systems.
High-performance dichroic beam splitters and mirrors providing sharp wavelength separation by reflection/transmission design. Thin-film coated for durability and minimal thermal drift.
Ideal for fluorescence imaging, microscopy, and multi-wavelength illumination systems.
Precision bandpass filters engineered for controlled wavelength transmission and maximum optical clarity across scientific and industrial imaging environments.
Ultra-narrow FWHM design (low nm-range) with plasma deposition coatings for laser cleanup, molecular analysis, cytometry, and biotech instrumentation.
Key applications: DNA sequencing, flow cytometry, atomic spectroscopy, biomedical assays
High-accuracy shortpass filters offering steep cut-off and low ripple for rejecting long wavelengths. Custom designs available.
High-transmission fluorescence filters, cubes, and wheels optimized for microscopy, flow cytometry, and high-NA imaging systems.
Engineered Raman optics including notch, edge, and laser line filters with high transmission, steep edges, and deep blocking for superior spectral resolution.
Precision ND filters for photometry, imaging, laser attenuation, and scientific exposure control without spectral distortion. Available in mounted and custom formats.
Ultranarrow laser line filters offering exceptional transmission at laser wavelengths and deep blocking outside the passband — ideal for Raman and fluorescence platforms.
UV pass filters for spectroscopy, photolithography, life-science imaging, and fluorescence excitation in the UV spectrum.
Optical Filter Glass:
Custom optical filter glass solutions for OEM systems — includes UV/IR blocking, color filters, density filters, and custom absorption/transmission profiles.
Optical Glass Filters:
High-reliability glass-based filters including color, UV, IR, polarizing, and neutral density options for image correction and environmental durability.
Dielectric and metal-dielectric bandpass filters engineered to precise CWL and FWHM specifications. Available for laser, biomedical, aerospace, and hyperspectral systems.
Spectral filter glass featuring calibrated peak wavelengths, cut-on/cut-off points, and defined FWHM for robust performance in demanding environments.
Color Temperature Insulating Filter Glass:
Filters engineered to balance spectral emission for thermal and color-temperature-critical optical systems. High color index (>90) with controlled spectral conversion.
Affordable and fully customizable colored optical glass filters, including bandpass, longpass, and color-balancing options for R&D and instrumentation.
Key Technical Parameters
Category |
Parameter |
Definition |
Critical Specifications & Considerations |
I. Spectral Performance |
Center Wavelength (CWL) |
Midpoint of the filter’s passband (for Bandpass filters). |
Tolerance (e.g., ± 0.5 nm). Shift occurs with AOI and Temperature. |
Bandwidth (FWHM) |
Full Width at Half Maximum—spectral range at ≥ 50 % peak transmission. |
Tolerance (e.g., ± 2 nm). Defines spectral resolution. |
|
Peak/Average Transmission (Tp/ Tavg) |
Maximum percentage of light transmitted in the passband. |
Aim for >90 %. Crucial for maximizing Signal-to-Noise Ratio (SNR). |
|
Cut-On / Cut-Off λ |
Wavelength at 50% of peak transmission for Longpass/Shortpass filters, respectively. |
Tolerance (e.g., ± 1 nm). Defines the passband edge. |
|
II. Rejection & Blocking |
Optical Density (OD) |
Measure of light attenuation: OD = – 10log Transmittance. |
Specified OD level (e.g., OD6 = 0.0001 % T) required for out-of-band rejection. |
Blocking Range |
Wavelength range over which the minimum specified OD is maintained. |
Must cover the entire source emission range and unwanted background noise. |
|
Passband Ripple |
Variations in transmission within the passband Tp). |
Low ripple (e.g., <5%) is needed for uniform spectral response. |
|
Edge Steepness (Slope) |
The rate of transition from the blocking region to the passband. |
Often defined by the distance between 10% and 80% transmission points. Steeper is better. |
|
III. System Context |
Angle of Incidence (AOI) |
Angle at which the light strikes the filter (typically 0°). |
Non-zero AOI causes a predictable spectral blue shift and can introduce polarization effects. |
Cone Half Angle (CHA) |
The half angle of the cone of light (related to the system f-number). |
Larger CHA (faster f/#) causes CWL shift and bandwidth broadening. |
|
IV. Physical & Environmental |
Substrate & Coating Type |
Material (e.g., Fused Silica, Borosilicate) and coating method (e.g., Hard-Coated Dielectric). |
Impacts thermal stability, durability, and ability to clean the filter. |
Operating Temperature |
The temperature range for guaranteed performance. |
Specify the Thermal Drift Coefficient (e.g., ~ 10 pm/C°) |
|
LIDT (Laser Filters) |
Laser-Induced Damage Threshold (e.g., J/cm2 or W/cm2). |
Mandatory for high-power laser systems; depends on pulse duration and repetition rate. |
|
Clear Aperture (CA) |
The guaranteed usable area of the filter. |
Must be adequately sized for the beam without vignetting. |
|
Surface Quality & Flatness |
Scratches/Digs (e.g., 60-40) and wavefront distortion (e.g., λ/4). |
Critical for imaging applications to maintain wavefront quality and minimize scatter. |
We support custom coating materials and layer designs optimized for the target wavelength and application environment.
Custom Optical Filters for Advanced Applications
Avantier supplies precision filters for:
- Semiconductor inspection & photonics
- Biomedical imaging & molecular diagnostics
- Laser systems & beam conditioning
- Aerospace and defense optics
- Industrial automation & machine vision
Request a Custom Filter Consultation
Whether you need prototype development, OEM production, or custom wavelength tuning, our optical engineering team is ready to support you.
Contact us today to request a quote or schedule a design consultation.
WE CAN HELP YOU!
Contact us NOW for sales & expert advice.