VERFAHREN UND EINRICHTUNG ZUM HALTEN EINES DÜNNEN MEDIUMS ZWISCHEN ZWEI KÖRPERN

摘要

PCT No. PCT/DK93/00180 Sec. 371 Date Nov. 28, 1994 Sec. 102(e) Date Nov. 28, 1994 PCT Filed May 25, 1993 PCT Pub. No. WO93/24327 PCT Pub. Date Dec. 9, 1993A method and apparatus for the illumination of points on a medium by illuminating a plurality of perforations that are arranged parallel to the medium with light having a center wavelength lambda . The perforations have a cross-section so as to provide for each perforation a diverging bundle of rays formed by defracting the light. The medium is positioned from the perforations at substantially the transition of the diverging bundle of rays between the Fresnel region and the Fraunhofer region.