Digital radiography for inspection of plastic electronics

PlastronicSpec: Automated digital radiography system for the inspection of plastic electronics

Background

Plastic electronics is a relatively young technology to be used in consumer electronics products. Nevertheless, the plastic electronics global market is forecast to grow as much as £143bn by 2027. Plastic electronics are mostly printed or sprayed on, rather than etched using expensive photolithography systems. Therefore this technology offers a number of advantages over existing printed circuit board manufacture techniques, including low cost and physical flexibility. However, numerous types of defects can arise during manufacture which are specific to plastic electronics and are discovered only after production, leading to high product waste and correspondingly high prices, which threatens the market promise. Specifically, organic light emitting diodes (OLEDs) used in digital displays need to be checked for quality. The OLED inkjet printing process can result in defective pixels, resulting from cracks, chips, pin holes and misaligned layers.

Objectives

The goal of PlastronicsSpec was to perform rapid, online, high-resolution and 100 per cent volumetric inspection by digital, real-time radiographic imaging. Emphasis was on the development of an in-line automated digital radiography inspection system with high throughput and advanced image pattern recognition links. The PlastronicsSpec project developed a system able to perform rapid and high-resolution inspection of printed plastic flat panels or reel-to-reel flexible electronics sheet using real-time digital radiographic imaging. This enables the automatic detection and instant rejection of defective products with minimum wastage and the elimination of human error in data interpretation.

The main features of the PlastronicsSpec system are:

• a microfocus X-ray source and a 2D flat panel digital detector which generates radiographs with up to 1.2μm resolution at high magnification
• prototype can accommodate a 600mm2D flat OLED panel and can be adapted to handle roll-to-roll flexible electronic samples
• novel multimode signal processing options have been used to detect the smallest possible image differences. Various image-filtering techniques have been integrated to achieve optimum pattern recognition and accurately size defects. The software allows automatic sentencing of parts as good or bad.

Benefits

By assuring defect-free products, the PlastronicsSpec project provided an enabling technology for the achievement of a mass market in plastic electronics products.

Partners

• Accent Pro 2000
• CETEMMSA
• Intrinsiq Materials
• Oled Technologies and Solutions
• ORME
• TWI NDT Validation Centre
• Brunel University London

Meet the Principal Investigator(s) for the project

Professor Tat-Hean Gan - Professional Qualifications CEng. IntPE (UK), Eur Ing BEng (Hons) Electrical and Electronics Engg (Uni of Nottingham) MSc in Advanced Mechanical Engineering (University of Warwick) MBA in International Business (University of Birmingham) PhD in Engineering (University of Warwick) Languages English, Malaysian, Mandarin, Cantonese Professional Bodies Fellow of the British Institute of NDT Fellow of the Institute of Engineering and Technology Tat-Hean Gan has 10 years of experience in Non-Destructive Testing (NDT), Structural Health Monitoring (SHM) and Condition Monitoring of rotating machineries in various industries namely nuclear, renewable energy (eg Wind, Wave ad Tidal), Oil and Gas, Petrochemical, Construction and Infrastructure, Aerospace and Automotive. He is the Director of BIC, leading activities varying from Research and development to commercialisation in the areas of novel technique development, sensor applications, signal and image processing, numerical modelling and electronics hardware. His experience is also in Collaborative funding (EC FP7 and UK TSB), project management and technology commercialisation.

Related Research Group(s)

Brunel Innovation Centre - A world-class research and technology centre that sits between the knowledge base and industry.

Project last modified 16/03/2021