Integrated-optical arrangement for bidirectional optical message or signal transmission

An integrated optical arrangement for bidirectional optical message and signal transmission characterized by a common substrate having integrated thereon, a semiconductor laser, an optical detector and a direction selective coupling arrangement which coupling arrangement has a first port coupled to the laser, a second port coupled to the detector and a third port arranged for coupling light in and out of the arrangement with a first wavelength from the laser passing from the first port to the third port and the third port passing a second wavelength to the second port for detection. The arrangement further includes a wavelength selective filter being disposed in a waveguide extending to the second port for blocking light of the first wavelength but being transmissive to light of the second wavelength. The coupling arrangement can either be an optical directional coupler or a y-shaped waveguide fork.