Rapid Prototyping of Complex 3D Optical Components
Nowadays complex 3D optical components with (sub-) microstructures on the surface of bulk optics become more and more attractive for different applications. Such examples can be found in lighting systems, optoelectronics, photonics, image processing, machine vision and motion control systems. Adding an additional optical functionality to a bulk 3D optic by placement of microstructures on the optic’s surface has enormous potential in terms of miniaturization of optical components, improvement of system integration and reduction of costs. Nevertheless, the development of complex 3D optical components with novel functionalities poses some technological challenges in design and fabrication. In this work, we report on a novel method to fabricate unique optical components, which exhibit the concept of ‘micro on 3D macro’. To demonstrate the possibility for rapid-prototyping of such optical components, 3D printing, direct-write laser lithography and 3D molding are combined into a novel process chain. The individual fabrication steps are discussed in order to point out the critical issues such as obtaining an optically smooth surface and shape accuracy of the 3D printed macroscopic objects to be suitable for the use in the field of optics. Some examples of successfully fabricated complex 3D optical components combined with patterned surfaces are demonstrated. These optical components are characterised extensively by means of optical microscopy, atomic force microscopy, scanning electron microscopy and 3D stripe light scanner. Afterwards the data are compared to the corresponding CAD models in order to determine the shape accuracy and dimensions. In conclusion, an outlook of the possibilities of the ‘micro on 3D macro’ concept for low-cost fabrication of plastic optics is presented.