A color regulator for testing RGB LEDs has been unveiled by Mazet GmbH. The device readjusts the combination colors of LEDs to the point where no difference is noticeable to the human eye. It can be used to compensate for temperature and aging effects. Color ratios are controlled via pulse-width modulation and can be set from a PC via a serial interface. The combination colors are respectively visible on a diffuser disc and can be directly compared with each other.