With the development of electronic manufacturing industry,EMS  companies paid more and more attention to automatic optical inspection (AOI).AOI suppliers, are clamouring for attention and a way to differentiate themselves in a crowded market. Price competition has thinned profit margins for both users and vendors.Yet AOI has still not achieved its original performance goals.

Reasons why AOI failed to meet performance targets.

On the user side, companies implement AOI on a wider scale,and spend Millions of dollars; yet in most factories, an operator is  still standing at every machine to verify defects. The issue of false alarms has become one of the keys to unlocking the potential of AOI. The data from an AOI system is corrupted by false alarms ,the information generated may be useless for statistical process control (SPC).The expected labour savings and improved yields were  not occurred. While end-of-line defects reduced, there was no significant reduction in rework .

Programming time is another paramount issue. Additional cameras also impact programming time, inspection time, and false alarm rates. Today, many users are attempting to find a balance between defect captures and low false alarms.When evaluating AOI systems, you must look at the time it takes from programmer to inspection cycle.

Proper use of AOI is still an issue, even in large manufacturing installations with years of experience. In some cases,the operators set the AOI parameters wider to reduce the number of alarms, rather than adjusting the production process to reflect the data developed from AOI. This defeats the original purpose of AOI.

How to improve the efficiency of AOI?

Proper and regular training is critical for successful implementation. An AOI system that may cost several hundreds of thousands of dollars,it is importernt to training of the operator running it. Well-trained operators produce better results.The long-term goal must be process improvement.so, It takes good equipment, well-trained operators, and accurate data to realize the expectations of AOI.

How does VCTA solve the problem?

VCTA AOI systems expressly designed to address many of the issues identified above.

▲Various vector image algorithms to get the best inspection capability.The vector image algorithms include logic operation, distance of luminance boundary, chip tracing, OCR/OCV, luminance/color template matching, color distance, color extraction (RGB & HSV), value-range of luminance, offset of luminance, the minimum variation span of luminance, etc… More than 30 kinds of the most advanced algorithms.

vector algorithms

vector algorithms

▲Industrial cameras with telecentric lens, can acquire hundreds of images per second.Combined with the software’s matching algorithm, can be used detect extra parts, foreign matter, scratches and other information on the PCB.

▲The new light source design, effectively eliminate the NG parts.

Offline programming

▲The entire PCB match capability can detect extra parts at any location.

▲Central server mode , gathers information from all the test machines , multiple machines need only one operator.

Multiple machines need only one operator.

Multiple machines need only one operator.