The InxGa1−xAs/InyGa1−yAs strained‐layer superlattices can be grown lattice matched to an InP substrate if proper compositions and thicknesses are chosen. Such structures were grown by molecular‐beam epitaxy. The wavelength range covered by this material is from 1.65 &mgr;m to beyond 2 &mgr;m. Structural (double x‐ray diffraction) and optical (absorption) characterizations were performed and quantitatively interpreted; they show the excellent properties of these structures.