The importance of additive manufacturing for optical components and systems is steadily increasing. Conventional 3D printing processes such stereo lithography (STL) are used to realize passive optical components. The challenge is thereby the surface quality and the volume scattering of the components produced. Irrespective of this, 3D printing of passive optical components has a wide variety of application fields, especially for illumination. The next step in additive manufacturing of optics is to achieve a higher functionalization of the components, thus turning form passive optical components to active optical systems. Thereby, it is an exciting and challenging question, if one can 3D print a laser completely additive. Therefore, we tried two different approaches. The first approach is comparable to a plastic optical fiber amplifier. For this purpose, laseractive nanoparticles (Nd-YAG) were incorporated into a resin and 3D-printed using a STL system. Due to the DLP projector of the STL system, one can realize a periodic change of the refractive index within the printed sample. Thus, the 3D printed cavity is comparable to a bundle of several thousand active fibers (given by the resolution of the projector). In this way, a POF amplifier was realized. The creation of a 3D printed resonator out of this is challenging and will be discussed. Alternatively, we realized a random laser with the aid of additive manufacturing. For this purpose, we mixed the printing material with Rhodamine and nanoparticles. Finally, the laser was 3D printed. We will discuss the performance of this device as well.
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