Development and implementation of a laser headlight system for electro‐optic characteristic measurement and comparison

Summary In this study, a laser headlight driving controller (LHDC) using the controller area network (CAN)‐bus communication system was developed and implemented for vehicle headlight applications. To observe temperature variations that influence the forward‐bias voltage and optical power of laser diodes, the laser diode was placed in an ambient temperature‐testing chamber to measure the electro‐optic characteristics and calculate the electro‐optic conversion efficiencies. The optical power and conversion efficiency values obtained at different temperatures (from negative to positive temperatures) when optical power adjustment was executed using analog and pulse‐width modulation technologies were compared. Moreover, a human‐machine operating interface was developed using the LabVIEW software. Therefore, the LHDC and laser optical power can be controlled using a computer through the CAN‐bus communication system to control the LHDC and monitor it. The CAN‐bus port of the MCU with the CAN‐bus transceiver in the LHDC enables communication with the computer. When the computer commands the LHDC, the duty cycle ratio of the PDCS can be controlled by the MCU to adjust the OP of the BBLD.