DeFinder – Shearography

Optrion’s DeFinder is a shearography-based non-destructive testing (NDT) solution designed to deliver fast, full-field, contact-free inspections with quick setup. The system is presented as making shearography viable, reliable, and affordable for NDT.

The portable DeFinder 4200 integrates the laser and optics in a robust, lightweight head (about 5 kg). It connects via USB and is automatically recognized by the Windows software. The setup is taking less than 15 minutes, with inspections covering up to 1 m² per acquisition using a 5 MP sensor.

For automated and repeatable production lines, the DeFinder 4300 supports TCP-IP communication, image stitching to analyze complete scans, and an IRT inspection option. Optrion cites inspection rates of about 3 min/m² in automated scenarios.

The software guides users through: 

MEASURE → PROCESS → ANALYZE → REPORT.

It includes live acquisition of phase maps and unwrapped images, automatic post-processing of temporal sequences, measurement and annotation tools, and semi-automatic report generation.

The operating principle captures a reference image, applies a typically thermal stimulation to reveal micron-scale deformations, and compares the results, with real-time unwrapping to aid interpretation.

Demonstrated applications include Type IV hydrogen pressure vessels (CFRP with PA liner) with detection in thick sections at low internal pressure; marine sandwich structures for delaminations and local bonding issues; and aerospace composites where 36 impact defects were detected within minutes across four measurements (including a 70 mm defect and cracks up to 10 mm depth), with speeds reported up to 20× faster than ultrasound. In honeycomb and monolithic aerospace cases, defects of 6 mm and 12.5 mm were detected at all interfaces, up to 20× faster than ultrasound and 5× faster than thermography.