Ultraviolet (UV) filters are helpful in systems that need a certain range of UV wavelengths. Alfa Chemistry makes sure that we are at the forefront of the market by offering a variety of UV optics. Along with having UV optics in stock for quick turnaround, we also collaborate with our clients to develop customized optical solutions.
Alfa Chemistry can create UV filters to a customer's specifications for transmission in the germicidal UVC band between 200 and 280 nm. These UV filters, which include UV bandpass filters for particular UVC wavelengths and UV short pass filters for transmission through the UV region, can be used to make sure that only particular wavelengths enter or leave the optical system.
Custom UV Filter Solutions
UV Interference Bandpass Filters
Our custom interference bandpass filters ensure that light from either side is appropriately filtered by only transmitting particular wavelengths during UVC disinfection, which often match the principal wavelength transmitted by the light source. Our applications include:
- Krypton chloride (KrCl) excimer lamps (222nm)
- Low-pressure mercury lamps (254nm)
- UV LEDs (265nm, 273nm, and 280nm)
Alfa Chemistry offers customized UV bandpass filters made from layers of dielectric-coated film. All blocking regions are OD4 or better, ensuring that all unwanted wavelengths do not enter the system or detector.
Fig 1. Transmittance of the 300-400 nm band-pass Interference Filters. (Cavaleri T, et al. 2020)
UV Colored Glass Filters
Alfa Chemistry can create UV filters with a high UV transmission and a high visible light block above 400 nm. The UG1, UG5, and UG11 are our three primary UV tinted glass bandpass filter choices. Standard sizes are 25mm in diameter or 50x50mm. On request, Alfa Chemistry can also offer special sizes.
Because the transmittance of colored glass filters is independent of the angle of incidence, this makes them simpler to integrate into systems. For more intricate patterns, we can offer UV filter glasses that are molded in addition to normal filter glasses.
Fig 2. UV band-pass filter structure: the number of metal-dielectric pairs is chosen to optimize bandwidth and peak transmission. (a) Two-pair metal/ dielectric structure; (b) three-pair metal/dielectric structure. (Mu J, et al. 2013)
Our Advantages
All UV optical filters are put to the test at Alfa Chemistry's cutting-edge metrology lab to make sure they adhere to every requirement before being visually checked by skilled quality technicians to verify complete compliance. With our in-house state-of-the-art metrology lab, you can be sure that your optics will meet your requirements. Alfa Chemistry takes great satisfaction in the high quality of our UV optical filters, and you can trust that they will work perfectly with your UVC equipment.
For more information on how Alfa Chemistry can help you with your optical needs, please contact our dedicated sales team.
References
- 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.
- Mu J, et al. (2013). "Design and Fabrication of A High Transmissivity Metal-Dielectric Ultraviolet Band-Pass Filter." Applied Physics Letters. 102(21): 213105.