Single-Bounce Mirrors
At Incoatec we also have the technology to fabricate 2D collimating or focusing multilayer optics which use only one single reflection: the Single Bounce Mirror (SBM). The SBM has a toroidal surface of ultra high precision and is coated with laterally graded multilayers.
At first glance, the advantage of the SBM over the Montel double bounce optics seems obvious: a single bounce mirror provides more intensity than a double bounce mirror when optics of the same length are compared. The difference in intensity arises from the fact that if a typical multilayer reflectivity is 70 % for a single bounce, the reflectivity of a double bounce optic would be 49 % if both optics have the same quality. However, a more careful consideration shows that both optics differ in more aspects. Firstly, the spectral purity of the double bounce optics is obviously much better than that of single bounce optics. Secondly, the double bounce optics has beam properties (beam size, divergence, and source usage) that are symmetrical in horizontal and vertical directions. This is generally not the case for the single bounce optics. Careful experimental work shows that the brightness (flux density / divergence) of the two schemes is almost identical. Since brightness is essential for SCD applications, our major OEM partner Bruker AXS prefers to use double bounce optics in their applications.
However, there are applications where a Single Bounce Mirror could be the better choice. Do not hesitate to contact us if you need technical advice on finding out which optics is best suited for your application - we are the only company worldwide offering both technologies.
