In this letter, we report on the fabrication and characterization of InAs-InP (100) quantum-dot (QD) Fabry-Perot and ring lasers, lasing in the 1.55-mum wavelength range and employing narrow deeply etched ridge waveguides (1.65 mum width). The performance of the lasers appears not affected by sidewall recombination effects of the deeply etched waveguide structure. Narrow deeply etched ridge waveguides can be mono-mode and allow for a small bending radius to realize compact integrated devices. As a demonstration, we present results on a compact ring laser with a free spectral range close to 40 GHz. Due to the low absorption of the QDs, unpumped output waveguides can be used