He began experimenting with light-emitting diodes, LEDs,at his laboratory at the University of Calgary in Alberta.

VOA: special.2009.12.21

Among the products were TVs that use light emitting diodes, or LEDs,to save energy.

VOA: special.2010.01.26

Back in his laboratory at the University of Calgary,Alberta, he experimented with light emitting diodes, technology he was familiar with as a professor of renewable energy.

VOA: standard.2009.12.13

The answer is light emitting diodes or LEDs.

VOA: standard.2009.12.13