Vision Technology

The vision systems of placement machines are critical for their accuracy and speed. Modern vision systems use stationary and/or head-mounted cameras in combination with additional sensor technologies such as laser measurements for coplanarity testing. The primary job of a vision system involves determining the position of components and boards as well as validating the component quality. With a properly functioning vision system, defective components can be detected and discarded within a few milliseconds. Modern systems are also able to detect barcodes, classify ink spots and calibrate machines. All of these tasks make the vision system the placement machine’s central sensor. In other words, the quality of the vision system plays a major role in the professional evaluation of placement solutions.

Quality characteristics

Vision systems are highly specialized measurement modules with special optics, sensors and analytical algorithms. To coordinate their camera technology, lighting, signal traffic and image processing, leading equipment manufacturers like SIPLACE maintain special teams of development and support experts.

High resolution for each component

During the inspection process, it is critical that each component is photographed with the highest possible resolution (number of pixels). That’s why the most powerful systems take a picture of each individual component (for maximum resolution and optimum focus).

Lighting

Many vision systems continue to use the backlighting process, which makes only the components’ contours visible and generally ignores any features within their outline. Components like BGAs or PLCCs, however, require front light systems for a detailed inspection that make all their structures visible to the camera. Additional improvements can be achieved with adjustable lighting levels.

Algorithms

The algorithms used in vision systems must be exceptionally robust, accurate and fast so that the inspection process does not slow down the placement process.

Vision teaching and vision dumps

Using special offline teaching equipment, users can adjust the cameras, lighting systems and algorithms for new components within seconds and away from the production line. That way, new product introductions can be implemented quickly and reliably. Modern vision systems also support the analysis of discarded components. Based on adjustable parameters, they store images of discarded components for subsequent quality checks and analyses.