STP911: Improvement of the Damage Threshold of High Reflectivity Multidielectric Coatings 1.06 μM

    Geenen, B
    Société MATRA, RUEIL MALMAISON,

    Malherbes, A
    Société MATRA, RUEIL MALMAISON,

    Guerain, J
    Société MATRA, RUEIL MALMAISON,

    Boisgard, D
    Société MATRA, RUEIL MALMAISON,

    Friart, D
    Société MATRA, RUEIL MALMAISON,

    Garaude, F
    Société MATRA, RUEIL MALMAISON,

    Pages: 5    Published: Jan 1985


    Abstract

    Development of new high power laser for laser-matter interaction in C.E.A. Limeil requires the realization of H.R. coatings with damage thresholds above 8 J/cm2.

    MATRA's laboratory “couches minces optiques” (thin optical layers) production commercial mirrors was around 3.5 J/cm2 in 1982. In order to obtain better results we decided to improve the control of evaporation parameters such as:

    – vacuum and regulation of oxygene pressure by means of a mass spectrometer

    – better measurements of evaporation temperature and regulation of evaporation rate

    – measurement and control of substrate temperature by pyrometric observation and to automatize the process.

    These different measurements and controls enable us to establish new processing operations giving better evaporation condition.

    The result was an increase of damage threshold from 3.5 J/cm2 to 8 J/cm2.

    Keywords:

    Damage threshold, Evaporation deposition, Mass spectrometer, Evaporation temperature, substrate temperature, TiO, 2, /SiO, 2


    Paper ID: STP28984S

    Committee/Subcommittee: F01.19

    DOI: 10.1520/STP28984S


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