Simultaneous realization of ultra-large field of view (FOV), large lateral image size, and a small form factor is one of the challenges in imaging lens design and fabrication. All combined this yields an extensive flow of information while conserving ease of integration where space is limited. Here, we present concepts, correction methods and realizations towards freeform multi-aperture wide-angle cameras fabricated by femtosecond direct laser writing (fsDLW). The 3D printing process gives us the design freedom to create 180° × 360° cameras with a flat form factor in the micrometer range by splitting the FOV into several apertures. Highly tilted and decentered non-rotational lens shapes as well as catadioptric elements are used in the optical design to map the FOV onto a flat surface in a Scheimpflug manner. We present methods to measure and correct freeform surfaces with up to 180° surface normals by confocal measurements, and iterative fabrication via fsDLW. Finally, approaches for digital distortion correction and image stitching are demonstrated and two realizations of freeform multi-aperture wide-angle cameras are presented.

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Commercially available optical photoresists for femtosecond direct laser writing are mostly transparent and only cover a small range of optical properties. This limits the design possibilities of micro-structures and micro-optics. Although the fabrication of 3D-printed micro-optics has become state of the art, the field of spectral filtering seems to be widely unexplored. In this work, we present, evaluate and compare different methods that can be used to fabricate colored micro-elements based on the already available polymers by adding pigments or dyes to the photoresists or by dyeing the fabricated structures in a post-printing process. Both optical performance and spectral filtering results are promising and could enable integrated color filtering or hyperspectral imaging in the field of 3D-printed micro-optics.

Purpose of review Recently, several trials as well as registry-data analyses investigating the role of robot-assisted radical cystectomy with extra or intracorporal urinary diversion were completed and follow up matured. This review aims to comment on the current evidence-based findings and interpret the future role of the robotic approach as a part of the treatment of bladder cancer. Recent findings Numerous trials and registry-data analyses revealed no significant differences in progression-free and overall survival after open radical cystectomy or robot-assisted radical cystectomy irrespective of urinary diversion. Perioperative parameters, especially intraoperative blood loss, transfusions, thromboembolic events, wound infections and hospitalization were significantly increased in open radical cystectomy. Patients’ convalescence, and especially early postsurgical quality of life, was improved by the robotic approach. The highly demanding surgery itself displayed by a flat learning curve required more than 130 surgeries per institution to reach a stable plateau of complications. The performance of high-quality radical cystectomy irrespective of the approach was significantly increased in high-volume centres. Local recurrence occurs in 11% after radical cystectomy. Current research focuses on intraoperatively usable detection methods and instruments to minimize the risk of residual tumour cells. Summary Taken together, the total intracorporal approach in radical cystectomy holds the potential to improve perioperative parameters and reduces hospitalization without impairing oncological performance of the procedure. To provide best results for the patient radical cystectomy and especially the technically challenging total intracorporal procedure will gain importance in bladder cancer treatment but should be limited to high-volume centres.