Abstract: The perspective opportunity to fabricate gray-scale masks was given LDW-glasses (LDW - Laser Direct Writing) from Canyon Materials, Inc. LDW-glass blanks contain a large number density of coloring specks of silver in a surface glass layer. A focused laser beam is used to heat erase these coloring specks. Experiments on the influence of laser radiation on LDW-glasses was carried out using a circular laser writing system. The transmittance value from the blank of 0.1 - 5% up to 70 - 80% depending on laser beam power is obtained with the current write scheme. Results of research of LDW-glasses behavior in a wide range of laser beam scanning speeds are described. Laser pattern generation in LDW-glass including the spatial resolution is discussed. The technology of fabrication of continuous-phase diffractive elements was tested by making exemplary Fresnel lenses. Total 80% efficiency for quartz Fresnel lenses with minimal zone width of 8 $mu@m was readily achieved in the preliminary experiments.!13
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