Laser-Excited Acoustics (LEA) Technology

XARION's Laser-Excited Acoustics (LEA) introduces a groundbreaking alternative to conventional, contact-based ultrasonic testing: A pulsed laser generates ultrasound directly within the material, and the proprietary Optical Microphone detects it completely contact-free. This enables high-resolution imaging without coupling media, which is a decisive advantage for complex, sensitive, or porous components.

How LEA works

The laser excitation is based on thermoelastic ultrasound generation. A short laser pulse is absorbed at the surface of the part, causing a very small and rapid thermal expansion without damaging the material. This expansion launches broadband ultrasonic waves into the component. As the waves propagate, they interact with material boundaries, and defects such as disbonds, lack of fusion, cracks, voids, or delaminations. These interactions change the ultrasonic signal, for example its amplitude, time-of-flight, or frequency content. Part of the ultrasonic energy couples from the surface into the surrounding air and is detected contactless by XARION's broadband Optical Microphone. The resulting data can be displayed as A-scans, B-scans, and C-scans, similar to conventional ultrasonic testing.

Inspection Setups

The technology can be used in different ultrasonic inspection setups, with corresponding probes available for each. 

• Single-Sided Pulse-Echo Mode: Generation and detection are performed from the same side, allowing reflections from back walls, internal boundaries, or defects to be evaluated.
• Guided Wave Mode: Ultrasound propagates between two positions on the same side of the structure, applicable for example to certain bond-testing or crack-detection applications. This not only reveals where a defect is located, but also at what depth.
• Through-Transmission Mode: Ultrasound is generated on one side of the part and detected on the opposite side, used for example to inspect sandwich-structured composites.