STP1015: Laser Damage Studies of Several Acrylic Polymers

    Romberger, AB
    Pennsylvania State University, Berks Campus, Reading, PA

    Mullins, BW
    Pennsylvania State University, Berks Campus, Reading, PA

    Shaffer, AA
    Pennsylvania State University, Berks Campus, Reading, PA

    Hilbing, JF
    Pennsylvania State University, Berks Campus, Reading, PA

    Siegenthaler, KE
    Pennsylvania State University, Berks Campus, Reading, PA

    Deaton, TF
    Pennsylvania State University, Berks Campus, Reading, PA

    Chang, Y
    Pennsylvania State University, Berks Campus, Reading, PA

    Pages: 9    Published: Jan 1988


    Abstract

    The bulk laser damage resistance of several acrylic copolymers and of pure poly (ethyl)methacrylate (PEMA) were investigated with a 1.06μm wavelength pulsed Hd:YAG laser having a pulse length of 8 ± 2 ns and an e-2 radius spot size of 30 ± 0.7 ¼m. These materials were synthesized in the bulk after extensive filtration or distillation to remove absorbing dust particles. A correlation is made between the damage thresholds and the number of scattering centers per volume observed in a HeNe beam. The HeNe laser beam scattering in the sample was used as an indicator of the impurity content of the sample. In the course of this experiment a spatial filter was installed in order to make the focused YAG laser beam more nearly Gaussian. Comparison of results obtained from the filtered beam and the unfiltered beam (which is mathematically described as a sombrero function) indicated that previous characterization of the non-Gaussian beam provided an incorrectly low damage threshold value.

    Keywords:

    beam profile, bulk laser damage, damage threshold, laser damage, multiple-shot, plastics, single-shot


    Paper ID: STP18730S

    Committee/Subcommittee: F01.02

    DOI: 10.1520/STP18730S


    CrossRef ASTM International is a member of CrossRef.