In this thesis, we have established an optical measurement system to measure the device characteristics. We focus on the investigation of semiconductor optical amplifier, Fabry-Perot laser, and ring cavity filter. We used InP-based multiple quantum wells epitaxial wafer with modulation doping in the active layer. A 1.41 £gm symmetric InGaAlAs/InP quantum well structure is used to fabricate the optical waveguide ring resonator devices for the optical communication region at 1.55£gm wavelength. For the semiconductor optical amplifier and lasers, we designed two different types: Fabry-Perot Amplifier (FPA), and Traveling Wave Amplifier (TWA). The InGaAlAs-FPA structure has three lasing peaks at 1514 nm, 1528 nm, and 1544 nm. The InGaAlAs-TWA-a structure has only one peak at 1510 nm. The InGaAsP-TWA-b structure has a gross gain = 8.5 dB (wavelength = 1575 nm) at pumping current = 22 mA. We used Hakki-Paoli method and transparency current to calculate gain spectrum. For ring cavity filter, the optical spectrum has a FSR = 41.25 GHz.