This paper describes the past and the present status as well as the future prospects of red, high power laser diodes (LDs) for smart laser displays and concentrates on broad area LDs (BA-LDs) that include arrays and narrow stripe LDs (NS-LDs). Since luminosity increases as the wavelength shortens in the red region, LDs are designed to emit around 640 nm. The output of the state-of-the-art BA-LD, which exceeds 14 mW/μm with 638-nm wavelength and wall plug efficiency (WPE) of 35%, shows stable operation up to 8000 hours. NS-LD provides 150-mW output with 642-nm with a WPE of 21%. LDs might be improved for higher output with greater high wall plug effi ciency.
