Conference Agenda

The development of optical systems has a very long tradition, and innovation in this field is accelerating. From an optical design perspective, for example, the use of free-form surfaces and adaptive optics is opening up new possibilities in the architecture and design of optical systems. One key for innovation is to understand the special features of new technologies including their limitations. We present an optical architecture using adaptive freeform optics to enable a new type of fluorescence microscopy.

Multiple researchers have explored the use of 3D printed micro-optical components as interfaces to quantum point emitters by considering different designs and configurations. Typically, these designs involve parametric structures optimized in combination with idealized point source models, which is the standard approach used in the realization of imaging systems. By restricting the light emission into a limited angular extent, small NA optical beams can be obtained. This results in an increased photon collection efficiency by centimeter-scale optical objectives in comparison to the case of bare point emitters. However, although low NA beams can be obtained in this form, this does not guarantee that the obtained field profiles will match the required spatial distribution needed for maximizing the coupling of photons into single mode fibers. In our work, we propose a different approach for maximizing such a spatial field overlap condition. In order to realize this, we rely on well-known numerical routines used in the context of illumination design tasks. Finally, we compare the obtained designs to standard parametric 3D printed based interfaces, which have been used in the context of 3D printed micro-optical interfaces to single photon sources.

In this paper, we present a highly miniaturized static projection system for integrated optical applications. Our system, which is only the size of a grain of salt, is 3D-printed using a single two-photon lithography step, enabling easy integration with photonic chips or optical fibers with high alignment accuracy and low process complexity.

Unlike conventional projection slides that use a transmission function to locally absorb or block light, our approach requires an all-transparent approach to be printable using a single transparent resist material. To achieve this, we established a partially coherent projection principle that partly directs light out of the acceptance etendue, allowing us to generate gray values across the field of view and achieve all-transparent projection slides.

Our miniaturized projection system has significant potential for various applications, including metrology, sensing, and endoscopy. We believe that our work provides a significant advancement in the field of integrated optical systems and opens up new possibilities for a wide range of applications.

In recent years, 3D machining in glass for micro-components has seen a notable boost, notably with the development of a novel optical fabrication chain. This approach uses lasers for shaping and polishing, enabling the creation of complex mini-optics efficiently.

The process begins with selective laser-induced etching (SLE) to define the optics' outer shape and surface figure. Subsequent polishing, using a "one-shot laser polishing" technique, removes imperfections and reduces roughness in a single step, achieving optical-grade smoothness.

This fabrication chain is applicable to mini-aspheres as well, enhancing their production efficiency. Additionally, it allows for wafer-level production, where multiple mini-optics are interconnected on a single glass substrate. The innovative SLE wafer-level approach optimizes heat flow during polishing, ensuring uniformity and superior optical quality.

Freeform metal optics are critical components in advanced optical systems for applications ranging from laser technology to space exploration. Accurately measuring mid-spatial-frequency roughness (MSFR) on these surfaces is essential for ensuring optimal performance and quality control. We present a cost-efficient, high-precision deflectometry system designed to meet this crucial metrology need.

Our system utilizes a novel calibration method and surface reconstruction workflow to achieve nanometer-level precision in measuring mid-spatial-frequency roughness of freeform mirrors. The key components include a low-cost, lightweight, and compact-sized camera and display. We discuss the challenges in accurately calibrating the intrinsic and extrinsic parameters. We then describe our measurement approach, which employs a combination of Gray-code and sinusoidal patterns that are observed by the camera through the reflective surface. Finally, we present our algorithm for surface reconstruction based on phase difference minimization and compare our deflectometric results with those of interferometric measurements.

Our sensor demonstrates high accuracy in characterizing MSFR while offering advantages in cost and flexibility compared to conventional techniques. The system has potential applications in autonomous production architectures for efficiently manufacturing and inspecting multiple mirror components, addressing the demand for high-quality optical elements in various industries.