A band pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range, and it’s used to selectively transmit a portion of the spectrum while rejecting all other wavelengths.

Longpass filters are ideal for a variety of applications, such as gas monitoring, temperature, sensing, thermal imaging and motion sensing, etc. Longpass filters block shorter wavelengths and transmit longer wavelengths. Blocking can be from reflectance, absorption or a combination. Transmission in the pass band can be enhanced with an antireflection coating on the second surface.

Custom Truncated Doublet and Singlet Lenses from UNI Optics

We offer an extensive custom truncated doublet lens service. With our 30 year heritage of experience in the industry means we can always find the right product and specification for you, whether you require exotic materials, or exceptionally tight tolerances, we are confident in our ability to supply to your complete satisfaction. The table below is a brief overview of our doublet lens  and is not an exhaustive list. If your individual requirements are not met, then please contact our technical sales team who will be happy to advise.es and is n’t an exhaustive list. If your individual requirements are not met, then please contact our technical sales team who will be happy to advise.

Typical Specifications:

Typical materials: Flint (N/F2) and Crown (BK7)
                             Flint (SF6) and Crown (N-LAK22)
                             UV & IR materials on request
Diameter: 3mm to 200mm+
Focal length: 3mm to 1000mm+
Centration: < 3 arcseconds
Surface figure: < 0.1 fringe
Surface quality: < 10/5 Scratch/dig
Coating options: Single layer and BBAR coatings for UV/VIS/NIR with R.avg.<0.25%

More information on the achievable specifications for your individual application can be found by contacting our technical sales team.