Fig. 1. Schematic diagram of spatial resolved damage testing system.

Fig. 2. Nd:YAG laser beam position at the wavelength of 355 nm with $0.5\mathrm{J}/{\mathrm{cm}}^2$ laser peak fluence in (a) the beam profiler and (b) the CCD camera. The silver film was tested for beam position calibration.

Fig. 3. (a) Recorded picture of the sample before laser irradiation. (b) Defect damage position in the Gaussian beam after laser irradiation at the wavelength of 355 nm with $26.4\mathrm{J}/{\mathrm{cm}}^2$ peak fluence. The triple frequency splitter was tested for the defect damage threshold. The elliptical shadow with rings around it in the middle of the image is illumination light for observing the defect damage position in the CCD camera.

Fig. 4. Transmittance spectrum of the multilayer coating prepared via reactive e-beam evaporation.

Fig. 5. SEM images of defect damages: class A was irradiated by the 355 nm laser with fluence of (a) $5.69\mathrm{J}/{\mathrm{cm}}^2$ and (b) $7.16\mathrm{J}/{\mathrm{cm}}^2$, respectively; class B was irradiated by the 355 nm laser with the fluence of (c) $8.33\mathrm{J}/{\mathrm{cm}}^2$ and (d) $7.62\mathrm{J}/{\mathrm{cm}}^2$, respectively.

Fig. 6. Electric field of the triple frequency splitter by the 355 nm laser.

Fig. 7. (a), (b) SEM images and (c),(d) FIB images: class B defect damage morphology of the triple frequency splitter by the 355 nm laser irradiation with the fluence of (a) $9.15\mathrm{J}/{\mathrm{cm}}^2$ and (b) $6.81\mathrm{J}/{\mathrm{cm}}^2$, respectively; (c) and (d) recorded depth information of class B defect damage morphology.

Fig. 8. SEM images of defect damages: class A was irradiated by the 532 nm laser with the fluence of (a) $5.26\mathrm{J}/{\mathrm{cm}}^2$ and (b) $7.12\mathrm{J}/{\mathrm{cm}}^2$, respectively; class B was irradiated by the 355 nm laser with the fluence of (c) $8.93\mathrm{J}/{\mathrm{cm}}^2$ and (d) $13.66\mathrm{J}/{\mathrm{cm}}^2$, respectively.

Fig. 9. Electric field of the triple frequency splitter irradiated by the 532 nm laser.

Table 1. Results of the Defect Damage Threshold of the Triple Frequency Splitter by Only the 355 nm Laser

Table 2. Result of the Defect Damage Threshold of the Triple Frequency Splitter by Only the 532 nm Laser