The HiLASE Centre would like to invite you to participate in the annual LIDT Challenge. In this annual edition, we are going to test a sample of your window with antireflective coating. As a reward, you will gain qualified knowledge of the respective damage threshold of your component.
Why should you take part?
The reliability of high-power lasers is largely determined by the optical components used in them. Therefore, knowledge of the quality of used optical components is essential for the safe and reliable operation of those laser systems.
How to participate & Conditions
Each participant will provide the HiLASE Centre’s LIDT laboratory with a sample of the highly reflective coated laser window, accompanied by a witness sample. Samples must be sent to the HiLASE Centre no later than 16 May 2025 to the following address:
HiLASE Centre – LIDT Challenge
Institute of Physics of the Czech Academy of Sciences
Za Radnici 828
252 41 Dolni Brezany
Czech Republic
The required sample diameter must be 2″ or 50 mm, 0° angle of incidence. The reflectance shall not be more than 0.2 % for p-polarisation at a central wavelength of 257 nm and all samples shall have a clearly marked front. The thickness of the samples shall not be less than 3 mm. Anonymised samples shall be tested by the s-on-1 method according to ISO 21254-2:2011 with a maximum of 106 (one million) pulses. The test laser will deliver 900 fs pulses in a circular, Gaussian beam with a repetition rate of 1 kHz with linear polarisation. The test will be performed at normal pressure, temperature between 22-24 °C and 30-40% relative humidity. The size of the test point will be 0,5 mm in the plane of incidence with a maximum fluence of 0,5 J∙cm-2.
Please make sure that your samples are properly packaged and labeled to avoid damage in transit or confusion with other samples. Also make sure that the sample you send is accompanied by an identical “twin” sample that can be used as a witness if necessary. Please mark your package clearly with the note “LIDT Challenge” to avoid confusion with other shipments we receive.
What will happen next?
You will have the unique opportunity to see the real performance of your elements in a high-end system, tested at our LIDT station. The anonymised results will be presented at the Laser World of Photonics in Munich (24-27 June 2025) as part of a planned workshop on innovative laser technologies organised by the Czech Optical Cluster, of which the HiLASE Centre is a member.
Why use HiLASE testing?
>We will use our high-energy, high repetition rate laser system PERLA to test the submitted samples.
We often see optical elements fail when used in high energy, high repetition rate systems, even though they work well when exposed to small diameter beams or low pulse counts. Therefore, we aim to maximize the laser beam diameter during measurements combined with long-term exposure to laser radiation, which, combined with the recommendations of ISO standards for LIDT, will ensure reliable results that reflect the robustness of the optics under real-world conditions. At the HiLASE Centre we provide state-of-the-art testing of materials and components for laser resistance under controlled conditions in our ISO 9001 certified LIDT laboratory.
To enter the competition, please contact us at lidt@hilase.cz and solutions@hilase.cz.
