R-on-1 LIDT test

R-on-1 test explained:

Use this test for:

• Testing of preliminary LIDT of surface limited samples (such as fibers or samples with small aperture: when S-on-1 is unavailable);
• Investigation of conditioning/annealing effect (in combination with 1-on-1);
• Only relatively compare production processes or vendors;

Test description

To perform an R-on-1 test procedure several test sites (minimum – 1, typically – 10, best – as as many as possible) are selected on the test area. Each of those sites is interrogated with a laser irradiation level (for instance, fluence) that increases step wise. Starting from very low irradiation values, it is linearly or non-linearly increased until a damage event is detected or the maximum irradiation level of the system is reached.  Based on the application each test site can be exposed to single or multiple laser pulses (S) at each irradiation level.

Known limitations and risks:

• Not suited for characterization of samples with low defect density;
• Not suited for large optics characterization;
• Provides only a rough (not accurate) estimate of LIDT value (order of magnitude);
• Continuous laser interaction with the material might also cause conditioning (annealing) or fatigue (accumulation or incubation) effects, which compromises LIDT accuracy;
• Might be time consuming if incremental fluence is too small;

Most popular test parameters for this test

⁽¹⁾ effective pulse duration measured at Full Width Half Maximum