Popis: |
Broadband antireflection coatings are indispensable for spaceflight refractive optics, suppressing the ghosting of images and increasing the throughput of the optical elements. These coatings are required to be resistant to abrasion and radiation exposure, while operating over a bandwidth of typically 2 or 3 orders. The range of available thin-film materials is therefore restricted for these coatings and so any optimization routine is likewise restricted in its search for an optimal design. Existing refining or synthesis methods1 modify multilayer antireflection coating designs to an extent, but there is still no guarantee that the final design is the best which can be achieved for the given design parameters. Choosing the coating starting design, thin film materials, optimization routine and target function is of paramount importance in achieving the coating with the best performance. A synthesis routine for a computer is therefore outlined which will achieve optimal broadband antireflection coatings for spaceflight use by a judicious choice of starting design and a powerful optimization routine. |