Light-emitting device and optical integrated device

An optical integrated device comprising:

• a first probe light irradiating line so configured that a probe light from a first light source is introduced into an optical waveguide and transmitted, comes incident via an objective lens obliquely at a prescribed angle to a perpendicular axis to an object surface and reaches an irradiation point;
• and a second probe light irradiating optical line having the same configuration as this first probe light irradiating line, and the optical integrated device having a configuration in which:
• these first probe light irradiating line and second probe light irradiating optical line are arranged in symmetric positions with respect to said perpendicular axis;
• and the two probe lights reach said irradiating point, wherein lights resulting from the reflection, scattering and diffraction of said probe lights from the object surface are condensed and re-introduced into light sources belonging to said probe light irradiating lines to be fed back to and detected in an active region.