MWIR On-axis Transmission Measurement of Lenses and Lens Assemblies.
Why spectral measurements of lenses are so important?
Most of the optical parts are lenses. Lenses come in vast variety of forms and sizes, both convex, concave, cylindrical and aspheric.
Lenses are coated in vacuum chambers when placed on the fixture or planetary rotation holder.
Due to the nature of the vacuum deposition process there is no possibility to measure actual transmittance or reflectance on lenses in a real time.
So flat witness samples are always used for process monitoring. However, the coating on lenses often differs from that on the witness sample.
For many applications, it is critical to know transmission of the real lens.
The actual optical performance can be often analyzed only once all lenses are installed in the optical system.
It may take substantial time and efforts to identify the «bad» lens.
These costs grow even higher for systems and objectives having multiple lenses. Needless to say, spectral performance of complete lens objectives also needs to be assessed!
LINZA 2752 spectrophotometer effectively addresses these challenges when it comes to on-axis transmission measurements of MWIR lenses and objectives. With its large compartment and sliding detectors, one can successfully measure individual lenes with diameter from 10 mm to 150 mm, and complete lens assemblies with end-to-end length up to 680 mm.
