The Laser Megajoule, an unprecedented technological challenge

Project Key figures

1
PW

This is the firing power of the PETAL chain

+10
yrs

This is the duration of the LMJ project

A few
µ

This is the alignment accuracy required of equipment in the center of the test chamber

1996: France ceases nuclear testing and launches the Laser Mégajoule project (LMJ). Aim: to extend the life of its nuclear deterrent by simulating explosions of nuclear weapons. An exceptional project in which the CNIM Group has been involved since 1999 with the manufacture of high-precision mechanical and optical devices.

A key installation in the Simulation program, the LMJ makes it possible to study on a highly-reduced scale the behavior of materials under similar conditions to those experienced when a nuclear weapon explodes.  After it had taken part in the LMJ preparatory program, in 2003 CEA/DAM (Military Applications Directorate of France’s Atomic and Alternative Energy Authority) awarded the Group a contract for Test Chamber Equipment and Integration (ECI), then in 2009 the contract for the Frequency Conversion and Laser Beam Focusing System (SCF), and finally in 2012 a contract for the PETAL transport and focusing chain. To ensure the successful completion of these projects, CNIM has called on its know-how in the fields of high-precision mechanical devices as well as remote-control and optics, which are specializations of Bertin Technologies.  We would point out that the firing accuracy required is the equivalent of aiming a laser beam from Earth at a football pitch on the Moon!

On-site tests were completed in 2014 and the LMJ was first introduced into service at a preliminary firing sequence carried out in the presence of Prime Minister Manuel Valls. Since 2015, the Group has cooperated with CEA/DAM in the operation of the systems already delivered and is preparing the production of future equipment. 22 laser chains are in fact planned in order to progressively increase power in the experimental process.

In 1996, we were far from being aware of the technological challenges the project would pose.  Today, the systems are operational and those challenges have been met, thanks to the collaboration of all the actors. CNIM has been involved in all the major stages and has seen the project through to the end. The equipment and materials delivered under its various contracts have proven their performance capabilities, some of them even surpassing CEA/DAM expectations.

Eric Huet, LMJ Project Manager, CNIM

The equipment designed and delivered by CNIM and Bertin bear witness to their technological genius and firm commitment alongside CEA/DAM and all the actors involved in this project of incredible complexity

Pierre Vivini, LMJ Project Manager, CEA/DAM