Case Study: NIR Dichroic, Beam-splitter for 1525 and 1550 nm

Case Study: Steep dichroic filter at 45 deg. angle of Incidence

Customer Challenge: This was for a space application for a sub-contractor to the European Space Agency, who were building a SWIR range spectrometer, a steep edge beam-splitter was needed to split 1525 and 1550 nm at 45° angle of incidence. The challenge lay in how steep the filter needed to be to ensure all planes of polarisation met the specification.

Vortex’s Solution: Using our software, we were able to design the filter and perform modelling to check that the proposed design would meet the above specification in both S and P planes of polarisation. The coating design could be downloaded into our coating machine and test samples manufactured for evaluation by the customer.

The Result: The transmission and reflection are shown in the spectral graphs above. Following successful testing by the customer, the ‘mission optics’ were manufactured with the same process. A wide range of space specific environmental testing was also conducted and fully recorded. Space missions often require filters that push the boundaries of development in low volume, Vortex are ideal partner for this type of work. Vortex also brings it’s learning from these projects to solve problems in the commercial world.