Optoelectronics research has been established at OES/ITRI since 1981. The R&D program started from compound semiconductor crystal growth. The major contribution is the development of a modified horizontal Bridgman method for growing GaAs single crystals. In the area of optoelectronic devices, both liquid phase epitaxy (LPE) and the metalorganic vapor phase epitaxy (MOVPE) are used to fabricate most of the light emitting diodes (LED), laser diodes (LD), and photodetectors (PD). The light sources with emitting light wavelength from visible 0.65 micrometers to 1.3 micrometers were made. Detectors, such as Si PIN and InGaAs PIN were developed. We are focusing on a new material system, i.e., AlGaInP. The LED and LD at the wavelength of 0.67 micrometers were grown by MOVPE. The threshold current is about 60 mA for a ridge-waveguide laser.