Large optics metrology for high-power lasers.

Area of Science:

• Optical Engineering
• Laser Physics
• Metrology

Background:

• The Laser MégaJoule (LMJ) is a significant high-power laser facility for laser-plasma experiments.
• An optical metrology laboratory was established at the CEA in the mid-1990s to support the LMJ construction.
• The laboratory's development was crucial for meeting the stringent optical requirements of the LMJ.

Purpose of the Study:

• To provide an overview of the metrology laboratory's capabilities for high-power laser optics.
• To highlight the specific challenges and solutions for optical metrology in the context of the LMJ.
• To showcase unique instrumentation developed for precise optical measurements.

Main Methods:

• Surface imperfection characterization using advanced optical techniques.
• Photometric measurements tailored for high-power laser environments.
• Laser-induced damage threshold (LIDT) assessment for optical components.
• Wavefront measurement and analysis for laser beam quality.

Main Results:

• Detailed capabilities in measuring surface imperfections on large-aperture optics.
• Established photometric methods for characterizing laser output and transmission.
• Quantified laser damage resistance of optical materials and coatings.
• Precise wavefront measurements to ensure optimal laser performance.

Conclusions:

• The metrology laboratory possesses comprehensive capabilities essential for the successful operation of the LMJ.
• The specialized instruments and methods developed offer unique advantages for high-power laser metrology.
• The laboratory plays a vital role in ensuring the quality and performance of LMJ optics.