Measuring Probes for Beam Scanning

Abstract

The invention relates to a measuring probe for scanning a light beam (10) or a laser beam. The measuring probe is suitable for direct scanning of a laser beam with very high power and for determining the geometrical parameters of the beam (10) with high spatial resolution and high signal-to-noise ratio, because the measuring probe is very sensitive to the inside of the measuring probe The multiple reflections are not sensitive. To this end, a device is proposed which comprises a scanning body (20) having a beam entrance surface (22), a beam exit surface (23), a sample light exit surface (25) and a probe region (30). The device also includes a detector (40) and means for providing relative motion between the scanning body (20) and the light beam (10). The scanning body (20) is rod-shaped and consists of a transparent light-guiding material. The scanning body (20) has a groove (21) for forming a surface portion (27) on the scanning body (20), the surface portion (27) comprising a beam entrance surface (22) or a beam exit surface (23). The normal direction (28) of the beam entrance surface (22) is inclined relative to the normal direction (29) of the beam exit surface (23) at an angle α ranging from 5° to 20°. The probe region ( 30 ) is arranged in a cross-sectional plane ( 26 ′) of the scanning body ( 20 ), which is located in the region of the groove ( 21 ). The cross-sectional dimension (D') of the scanning volume (20) in the cross-sectional plane (26') is the cross-sectional dimension (D) of the scanning volume (20) in the cross-sectional plane (26) outside the groove (21) at least 50% of the The probe region (30) has a light deflecting structure. A detector (40) is arranged for detecting at least a portion of the beam component (15) deflected from the beam (10) by the probe region (30).

Description

technical field [0001] The invention relates to a device for scanning a light or laser beam. The invention is suitable for determining geometric parameters such as the intensity distribution, beam profile or beam diameter in a cross-section of a light beam or laser beam. The invention can directly scan the laser beam with the maximum brightness and the power of kilowatts and thousands of watts without attenuating the laser beam in advance. The device can be used to scan a plurality of beam cross sections in different planes and thus also to determine beam parameter products, beam propagation factors or focus positions of laser beams. Due to the reduced susceptibility to interfering light reflections in the measuring probe, the invention enables measurements with a high signal-to-noise ratio and high precision. Background technique [0002] In order to describe light beams or laser beams, integral variables such as energy or power are used on the one hand. In addition, geo...

AI Technical Summary

Problems solved by technology

However, the beam to be measured may have to travel a longer path through the scanning volume before the beam is scanned by the probe area

This in turn can lead to undesired changes in beam characteristics due to refraction and thermo-optical effects, leading to inaccurate scan results

[0014] Therefore, the devices and methods known from the prior art have significant disadvantages in terms of usability, achievable spatial resolution and / or in terms of measurement accuracy or signal-to-interference light distance at very high laser powers or power densities

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