A laser apparatus includes a plurality of laser modules each generating a laser line in a working plane. The laser modules are juxtaposed so that the laser lines generated by the modules combine into a single laser line. Each of the laser modules includes at least one laser line generator and a laser line shaper. The laser line shaper includes an array of microlenses such that the final laser line generated by each laser module has, in the working plane, a power density profile with a width (L90) at 90% of the maximum power density and a width (L10) at 10% of the maximum power density. A ratio L90/L10 is between 1/15 and 1/5.