Like audio speakers, which can act as both loudspeakers and microphones, LEDs can both emit and receive light. Ketra designed a module in which most of the LEDs produce light and some receive it. These monitor LEDs send the information they’ve gathered back to the driver chip. If there is any change, the chip adjusts the frequency of the electrical current feeding the LED emitters. The effect of this closed feedback loop is that the chip can correct the LED module and maintain a consistent light level and color temperature. It can also dim the color temperature—from 10,000K down to 1400K—to produce warm, flicker-free light. With a little programming, it can put on a “circadian show,” mimicking the dynamic qualities of natural light throughout the course of the day and night. Ketra also equipped the driver chip with radio frequency capabilities, allowing it to talk to other modules and to be controlled wirelessly.