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Recent advances in planar optical integration

Optical technologies have changed the way people live since centuries, and the pace of knowledge creation and implementation has strongly increased in the recent past. Prominent examples of recent change include the speed with which information can be exchanged, allowing delay-free intercontinental communication, and the advent of the broadband internet. The conception of planar waveguide optics has already ignited fundamental and manufacturing research decades back, and its proclaimed uses were manifold, including data communication, bio analytics, or illumination. The advances in waveguide optics have also generated many approaches to integrate optical technology into packaging technology using fabrication methods known from the semiconductor or the printed circuit board (PCB) industry. These technologies allow planar integration of optical waveguides and support the miniaturization of integrated systems. With the first experiments dating back to the 1970's, the performance of planar integrated optical systems has risen from proof-of-principle to a point where it is becoming increasingly appealing for many applications to use planar integrated optical technology. A review of the state-of-the-art in integration technologies is given and the prospectus for the use of integrated PCB based optical links is assessed and favorable conditions for successful implementation are proposed.