3. Laser-Induced Damage Threshold Evaluation

Laser-Induced Damage (LID) is a complex physical phenomenon. Damage mechanism depends on various irradiation, material and environmental properties. Consequently, Laser-Induced Damage Threshold evaluation requires a specific knowledge base. In this glossary page you willl find a useful terminology and step by step explanation how LIDT is calculated in various situations. We strive to make this glossary useful and easy to understand. So we encourage our customers and readers to provide us a feedback and share their questions (contact: gintare@lidaris.com)

The LIDT test procedure is destructive: an intense laser radiation is applied on a sample surface, which is monitored for damage occurrence. There are several ways to relate damage event with threshold fluence. The most common approach is the so-called statistical damage frequency method (DFM) also known as damage probability method. Due to its wide application, the DFM was taken as a basis for the international standard ISO 21254 [1-2]. Herewith, we describe damage frequency method in three steps. Click on each step to find out more.

STEP 1 STEP 2 (upcoming) STEP 3 (upcoming)
‎Damage probability
LIDT evaluation
Evaluation of
test uncertainty
How damage probability
curve is constructed
from the measurement data?
How LIDT is extracted
from the damage
probability curve?
How accurate
reported LIDT
value is?
Damage_probability_ 3 Calculation Uncertianty 4



[1] Lasers and laser-related equipment – test methods for laser-induced damage threshold- Part 1: Definitions and general principles (ISO 21254-1:2011).
[2] Lasers and laser-related equipment – test methods for laser-induced damage threshold- Part 2: Threshold determination (ISO 21254-1:2011).

If you are interested in laser-induced damage phenomena we also highly recommend to read:

[3] D. Ristau, Laser-Induced Damage in Optical Materials (CRC press, Taylor &Francis Group, Florida, 2014).
[4] R. M. Wood, Laser damage in optical materials (A. Hilger, Bristol, 1986)