KOITO Manufacturing Co., Ltd and Denso Corporation along with Toyota Motor Corporation and Royal Philips Electronics, have developed the world's first mercury-free, high intensity discharge (HID) headlamp system.
This system completely eliminates mercury from discharge lamps (bulbs).
The HID headlamp system is installed on the Toyota Porte, launched this month in Japan.
The HID headlamp system has a newly developed mercury-free discharge bulb, as well as a controller (ballast) that controls lighting of the discharge bulb.
KOITO and Philips developed the mercury-free discharge bulb using a mercury substitute.
KOITO and Denso developed the ballast for lighting the mercury-free discharge bulb.
Together, these developments led to the world's first mercury-free HID headlamp system that provides bright lighting and long bulb life, equal to the conventional HID headlamp system.
In addition to adopting the mercury substitute for the bulb, the bulb’s tube design was changed to maintain the long bulb life.
To control the lighting of the newly developed mercury-free discharge bulb, the ballast was improved to apply increased initial operating wattage and operating current to the bulb.