Functional display testing

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By Bob Christensen | Feb 19, 2016
Functional display testing

In our previous blog article, Optical characterization testing, we explored the capabilities of GMN’s Light Lab. Now we’re focusing on another area of display testing; the functional tests. During the planning stage of a user interface device, functional testing is crucial. GMN provides both automated and manual testing services to meet a wide range of program requirements.

GMN’s automated functional testers provide computerized inspection services. These testers are equipped with vision inspection to subpixel resolution along with electrical testing for thermistor resistance and touchscreen resistance and capacitance. To further ensure the functionality of a touchscreen, a 9-point touch test is used to assess touchscreen performance. Another service growing in popularity is component traceability. Component traceability is done for both the touchscreen and LCD by recording component serial numbers in the inspection record, and then each assembly is assigned a unique GMN serial number for traceability of the entire assembly. Automated testing necessitates a longer testing period compared to manual testing and is optimal for high volume production runs that require data collection.

Another option for evaluating device functionality is manual testing. These tests are typically measured on a pass or fail basis. Human visual inspection is used to detect display issues such as pixel defects, lint, and bubbles. Handheld touch probes are used for the touchscreen functionality test.

Learn more about GMN display testing in our blog article: Optical characterization testing