Centre National De La Recherche Scientifique

Université Paris-Saclay

Institut Optique Theorique Appliquee

Centre Technique Des Industries Mecaniques

Pierre Pichon

François Balembois

Laurent Juras

Christophe BRIANÇON

Denis Espinassou

Damien Guillon

Didier Mastain

A laser pumping assembly includes a parallelepipedal solid laser medium having the shape of a plate in a horizontal plane (xy) and a thickness e, the laser medium having an absorption spectral band and an associated absorption coefficient α; at least one light emission module intended to pump the laser medium, comprising a fluorescent parallelepipedal crystal called a concentrator, having the shape of a plate of thickness e, the concentrator having at least one illumination face illuminated by electroluminescent radiation and being configured to absorb the electroluminescent radiation and emit fluorescence radiation in a spectral range exhibiting an overlap with the absorption spectral band, the concentrator having an emitting face; the concentrator being in optical contact, via the emitting face, with a receiving face of the laser medium, the concentrator being arranged perpendicular to the laser medium such that the one or more illumination faces are perpendicular to the receiving face so as to perform transverse pumping of the laser medium, the optical contact being designed such that a portion of the fluorescence radiation trapped in the concentrator by total internal reflection is able to pass into the laser medium by passing through the emitting face, and be trapped in the laser medium by total internal reflection, the thickness eof the laser medium being such that e≤L/5 where L=1/α is an absorption length of the laser medium.

T-shaped laser pumping device

A light-emission device includes at least one emission module comprising: a luminescent crystal known as a concentrator crystal with at least six faces which are parallel in pairs, including a first and a second face, known as lateral faces, perpendicular to a direction x and separated by a distance corresponding to a horizontal dimension of the concentrator in the direction x; a first mirror, which is configured such as to cover the first lateral face at least partly, defining a surface area covered by the first mirror, and at least one surface area (SFS) which is not covered by the first mirror defining an associated output face; a second mirror, which is configured such as to cover at least 95% of the second lateral face; a brightness triggering element, which is designed to generate emission of brightness radiation (L) in the luminescent crystal; a ratio R between the non-covered surface area (SFS) and a surface area (S) of the first lateral face being determined such that rays of the brightness radiation are reflected on the first and second mirrors, and are propagated over a mean distance Lsuch that within the luminescent crystal before passing through at least one output face, forming an output beam, where α is a coefficient of loss per unit of length of the concentrator for the brightness radiation.

3D concentrator

Growing community of inventors

PALAISEAU, France

Pierre Pichon