LED Panel Testing

Device Under Test (DUT):

Individual Light Emitting Diodes (LEDs) at the panel production level.


Requirement for an automated test platform to solve the challenge faced by electronic printed circuit board (PCB) manufacturers as a result of the growing demand for light emitting diode (LED) products and testing complexities. The test platform required specialized features to detect inconsistencies in the individual LEDs while maintaining the capacity associated with high-speed automated production lines.


Designed and implemented an automated process that combined advanced vision technology with flexible positioning and power-up capabilities. The test platform could efficiently handle multi-board test requirements and its detection capabilities ensured that the highest standards were met. Features included:

• High resolution LED imaging camera with electronic exposure control and custom photopic filter that measured LED color and luminous intensity, allowing for individual board pass or fail assessment.
• Specially engineered and integrated measurement board that handled both steady-glow and flashing LEDs, as well as under-driven power conditions.
• High performance camera and software recognition system to accurately correct individual board variations.
• Functional test requirements, including resistance, current, voltage and relay, that can be integrated based on customer specifications.
• High speed 4 axis programmable servo robot with quick change robot interface and custom end-of-arm-tooling provided the flexibility to handle individual or multiple board contact and power-up requirements.
• Precision lift-and-locate station for seamless inline integration and rapid reconfiguration for a wide variety of products.
• Intuitive PC-based control system for reliable performance and simplified programming of multi-product configurations.
• 2D barcode scanner and factory information system integration provided product and operator traceability.
• Integrated electro-mechanical inkjet or laser marking systems for individual board or panel identification.
• Optional LED image analysis software for detection of off-axis LEDs.
• Multi-language compatibility.

Winning Result:

The test platform greatly improved end customer satisfaction by accurately identifying and reporting problem boards. It increased profitability by reducing testing cycle times and labor costs. The system’s flexibility reduced new product changes to programming and tooling and minimized set-up, downtime and operator training.

Market Served: Automotive