Manufacturing problem contest [invited]

For the Manufacturing Problem contest, participants were asked to fabricate on provided blank substrates a challenging filter with specific reflectance and transmittance targets covering a wavelength range from 400 nm to 1100 nm. The problem was selected such that to achieve a performance close to the targets, a submitted filter had to include at least one thin absorbing layer. Nine teams from six countries participated in the contest using different deposition techniques. The teams' designs had a number of layers varying from 36 to 235, and a total thickness from 2.0 microm to 14.6 microm. The performances of all submitted filters were measured by two independent laboratories, and the results were presented at the Optical Interference Coating meeting in June 2016.