The following data was obtained using a Zygo Laser Interferometer (@632.8nm) to measure the influence of a freely suspended TurboFilm sample on the 100mm diameter transmitted wavefront. The first strip shows the interference fringes of the Zygo test reference surface with and without the TurboFilm. The resulting point spread functions (PSF) were then calculated from these results and are shown below the fringe views. These simulate the resulting view of a star at a telescope's focus. The resulting Strehl Ratio has also been calculated from the RMS value and listed below the star images. At the bottom are the respective 3D plots that further illustrate the wavefront surface. For comparison purposes, a similarly mounted 12micron MylarTM film has also been included.
The sample of TurboFilm achieved a wavefront RMS (and Strehl) better than many amateur telescopes. The MylarTM sample distorted the wavefront well beyond the permissible diffraction limit. Since AstroSolar is based on the TurboFilm substrate, the optical performance of AstroSolar provides identical results. These results show that TurboFilm and AstroSolar are very well suited for high resolution optical applications. Please note that the results are dependent on how the film is mounted. All strain and folds must be avoided, in order to prevent the potential for distortions in the wavefront. For an easy way to achieve this with a simple, inexpensive cell, please click on constructing a simple and inexpensive cell.
Anschrift: Paul Pleiger Maschinenfabrik GmbH & Co. KG
Dipl.-Phys. Peter Rucks
Im Hammertal 51
|Reference Flat (no film)
|TurbofilmTM, Strehl 96.8%
|MylarTM, Strehl 57.2%