Interference bandpass filters are ideally suited for applications requiring specific spectral tolerances. Researchers studying manufacturing processes have a high degree of control over transmission characteristics. Alfa Chemistry enables customisation of a variety of bandpass filters to meet the unique size requirements and spectrum needs of each customer. Our filters offer outstanding OD4 or OD5 out-of-band blocking capabilities and have a CWL range of 220 nm to 1064 nm. We provide the best infrared filter solutions by taking into account all design factors, such as requirements, cost, and lead time. Please get in touch with our technical sales team to learn more about your requirements for specialized interference bandpass filters.
Customized Service
Alfa Chemistry offers custom interference bandpass filters manufactured to customer specifications. We can alter the spectral properties in accordance with your application's needs, which include:
- Peak transmission: as a minimum, or adjusted to perform within a certain range.
- Out-of-band blocking: typically OD4 (T < 0.01%).
- Center wavelength (CWL) in the UV, visible or IR band.
- Bandwidth or FWHM: We can provide narrow band (< 10 nm), standard (10-50 nm) and broadband filters (> 50 nm).
Customers can find our typical manufacturing capabilities below. Spectral properties are influenced by things like design wavelength and bandwidth size. Consult our technical sales team for further details on the specifics of each filter.
In addition, it is important to note: Interference bandpass filters work with either side facing the light source. To lessen any heat impacts, we advise turning the "mirror" side toward the light source. Beam haloing might be necessary if the light source is larger than the actual filter area.
| Types Available | Interference, Dichroic, Polyester, Colour glass, etc |
| Dimensions | 12.5 mm to 100 mm diameter |
| Interference Type | 3 mm to 400 mm diameter |
| Dichroic Type | 100 mm * 300 mm |
| Wavelengths | 175 nm to 3200 nm+ |
| Bandwidth | 3 nm to 100 nm+ |
| Peak Transmission | > 85% |
| Surface Quality | < 10/5 |
| Parallelism | < 3 arcseconds |
Applications:
- Laser diodes and LEDs are frequently employed in conjunction with interference bandpass filters.
- In biotechnology, biomedicine, and quantitative chemistry use interference bandpass filters to selectively transmit a small range of wavelengths while blocking all other wavelengths.
- Interference bandpass filters are also used to separate a particular spectral line from Ar, Kr, Nd:YAG, and other lasers, as well as to pick discrete spectral lines from arc or gas discharge lamps (Hg, Xe, Cd, etc).
- Instruments for clinical chemistry, environmental testing, colorimetry, elemental and laser line separation, flame photometry, fluorescence, immunoassays, and other applications frequently employ interference bandpass filters.
Fig 1. Transmittance of the 300-400 nm band-pass interference filters. (Cavaleri T, et al. 2020)
Quality Assurance
Each custom-made interference bandpass filter is carefully tested to all applicable standards using state-of-the-art metrology equipment. We inspect and review each product before it is shipped to our customers, so they can be completely confident that the optics they order will be the best fit for their application.
Reference
- Cavaleri T, et al. (2020). "A New Imaging Method of Fluorescence Induced by Multispectral UV for Studying Historical Musical Instruments Coatings." Conservation 360°: UV-Vis Fluorescence Imaging Techniques.