An optical device according to an embodiment includes a laser light source, a first optical waveguide that propagates light being output from the laser light source, a first distribution device that distribute the light into n lights, n second optical waveguides that propagates the n lights being output from the first distribution device, n second distribution devices that distribute each of the n lights into m lights, n×m third optical waveguides arranged in a matrix form and propagates the n×m lights being output from the m second distribution devices, a control electrode that apply a voltage or current to each of the third optical waveguides, and control phase of the light propagating through the third optical waveguides, and an output end surface that output the n×m lights.