Experimental applications of adaptive
optics in industrial lasers

Leonid N. Evdokimovich, Peer Helms, Andrey G. Safronov, Bernd Tobke, Boris S. Vinevitch

Abstract

The next step on the way of improving laser technologies is the use of simplest elements of adaptive optics, in particular of one-channel deformable mirrors. We have use such molybdenum cooled mirrors for the intracavity control in different cw CO₂-lasers and for the out-of-cavity one of the laser piercing and cutting in industrial CO₂-laser machine. The base technical parameters of the used deformable mirrors are following: the maximum radiation power is 10 kW; the light aperture is 42 mm; the sensitivity (PV of deformation/voltage) ranges from 44 up to 49 m/kV; the frequency range is up to 1.0 kHz.

Fig.1. Output power Pout of cw CO2-laser vs control voltage UDM of the cooled deformable mirror. The voltage of 1 mV at the photosensor output (Ups) corresponds the output laser power (Pout ) of 680 W. 1 – Single-mode regime, warm water, Рout = 680 W; 2 – Рout = 238 W; 3 – Рout = 462.4 - 476 W; 4 – Рout = 727.6 – 734.4 W; 5 – Рout = 1054 - 1074 W; 6 – Рout = 1544 – 1598 W; 7 – Рout = 2101 W; 8 – Рout = 2033 W.

The intracavity applications of the mirrors were in 2-kW-cw CO₂-laser of "GARPUN-2000" (Russia) and 1-kW one of "HEBR-1A" (Bulgaria); both lasers have a stable cavity. In these cases, we have achieved the following results.

1. Under the quasi-static control signal applied to the intracavity deformable mirror, the regimes of a controllable output radiation power have been provided for both lasers (as an example, see fig.1). Under the control signal of a definite value, the lasing is suppressed.
2. When the ac control voltage applied to the mirror, a pulse regimes of generation have been achieved in both cw CO₂-lasers.

The laser piercing and cutting, using deformable mirror, were carried out on industrial 6-kW-cw CO₂-laser machine of "LFP – Laserbeam cutting and welding system" (Germany). As a workpiece, we have use the stainless steel of 1.4301/V2A having the thickness of 12 mm. For these technologies, we have achieved the following results.

1. For the pulse piercing technology using deformable mirror, the piercing time was less two times than one for the same processing without deformable mirror.
2. For the laser cutting technology, the thickness of high-quality cutting was increased essentially.

In conclusion from our point of view, the given results open the wide possibilities for extensive and intensive industrial applications of the simplest adaptive optics, for example in automobile and ship industries.

[Main] [Products] [Price] [Publications] [FAQ] [Forum] [Contacts] [Mail]