Search

The growing interest in 3D printing of silica glass has spurred substantial research efforts. The prior work utilizing a liquid silica resin (LSR) demonstrated high printing accuracy and resolution. However, the resin's sensitivity to moisture posed limitations, restricting the printing environment. On the other hand, polyhedral oligomeric silsesquioxane (POSS)‐based materials offer excellent water stability and sinterless features. Yet, they suffer from relatively high shrinkage due to the presence of additional organic monomers. In this study, a polymeric silsesquioxane (PSQ) resin is presented with reduced shrinkage, enhanced moisture stability, and the retention of sinterless features, providing a promising solution for achieving high‐resolution 3D printing of glass objects. Leveraging the two‐photon polymerization (2PP) method, nanostructures are realized with feature sizes below 80 nm. Moreover, the tunability of the refractive index is demonstrated by incorporating zirconium moieties into the resin, facilitating the fabrication of glass micro‐optics with varying refractive indices. Importantly, the self‐welding capability observed between two individual components provides a flexible approach for producing micro‐optics with multiple components, each possessing distinct refractive indices. This research represents a significant advancement in the field of advanced glass manufacturing, paving the way for future applications in micro‐ and nano‐scale glass objects. [ABSTRACT FROM AUTHOR]

To address the major challenges to obtain high spatial resolution in snapshot hyperspectral imaging, 3D printed glass lightguide array is developed to sample the intermediate image in high spatial resolution and redistribute the pixels in the output end to achieve high spectral resolution. Curved 3D printed lightguide array can significantly simplify the snapshot hyperspectral imaging system, achieve better imaging performance, and reduce the system complexity and cost. Two‐photon polymerization process to print glass lightguide array is developed, and the system performance with biological samples is demonstrated. This new snapshot technology will catalyze new hyperspectral imaging system development and open doors for new applications from UV to infrared. [ABSTRACT FROM AUTHOR]

In recent years, 3D printing glass optics has gained massive attention in industry and academia since glass could be an ideal material to make optical elements, including the lens. However, the limitation of materials and printing methods has prevented 3D printing glass optics progress. Therefore, we have developed a novel printing strategy for germanate glass printing instead of pure silica. Moreover, compared with traditional multi-component quartz glass, germanate glass has unmatched advantages for its mid-infrared (MIR) transparency and outstanding visible light imaging performance. Furthermore, compared with non-oxide glass (fluoride glass and chalcogenide glass), germanate glass has much better mechanical, physical, and chemical properties and a high refractive index. Germanate glass has been widely applied in remote sensing, ranging, environmental detection, and biomedical detection. However, it is difficult to shape, cast, polish, and grind for optical and photonics applications such as imaging optics and laser-collimation optics. These drawbacks have made germanate glass inaccessible to complex optical elements and greatly increased their cost. In this report, we use germanate glass fibers with a diameter of 125 µm based on fiber-fed laser heating technology to fabricate an mm-size optical application. In this paper, we combine the fiber-fed laser heating technology with an optimized temperature control process to manufacture high-precision optical elements. Germanate glass optics can be printed with excellent visible light and IR transparency and a smooth surface with roughness under 4 nm. By optimizing the layer-by-layer 3D printing process and the thermal feedback in the printing process, we avoid cracks and minimize surface deformation. This work shows the possibility of the mm-size glass optical elements 3D printing and widens its application for IR optics. [ABSTRACT FROM AUTHOR]

3D printing of optics has gained significant attention in optical industry, but most of the research has been focused on organic polymers. In spite of recent progress in 3D printing glass, 3D printing of precision glass optics for imaging applications still faces challenges from shrinkage during printing and thermal processing, and from inadequate surface shape and quality to meet the requirements for imaging applications. This paper reports a new liquid silica resin (LSR) with higher curing speed, better mechanical properties, lower sintering temperature, and reduced shrinkage, as well as the printing process for high‐precision glass optics for imaging applications. It is demonstrated that the proposed material and printing process can print almost all types of optical surfaces, including flat, spherical, aspherical, freeform, and discontinuous surfaces, with accurate surface shape and high surface quality for imaging applications. It is also demonstrated that the proposed method can print complex optical systems with multiple optical elements, completely removing the time‐consuming and error‐prone alignment process. Most importantly, the proposed printing method is able to print optical systems with active moving elements, significantly improving system flexibility and functionality. The printing method will enable the much‐needed transformational manufacturing of complex freeform glass optics that are currently inaccessible with conventional processes. [ABSTRACT FROM AUTHOR]

Microendoscopes are commonly used in small lumens in the body, for which a focus near to the distal tip and ability to operate in an aqueous environment are paramount for navigation and disease detection. Commercially available distal optic systems below 1mm in diameter are severely limited, and custom micro lenses are generally very expensive. Gradient index of refraction (GRIN) singlets are available in small diameters but have limited optical performance adjustability. Three-dimensional (3D) printed monolithic optical systems are an emerging option that may be suitable for enabling high performance, close-focus imaging. In this manuscript, we compared the optical performance of three custom distal optic systems; a custom-pitch GRIN singlet, 3D-printed monolithic doublet, and 3D-printed monolithic triplet, with a nominal working distance (WD) of 1.5mm, 0.5mm and 0.4mm in 0.9% saline. These short WDs are ideal for microendoscopy in collapsed or flushed lumens such as pancreatic duct or fallopian tube. The GRIN singlet had performance limited only by the fiber bundle relay over 0.9mm to 1.6 mm depth of field (DOF). The 3D printed doublet was able to achieve a comparable DOF of 0.71mm, while the 3D printed triplet suffered the most limited DOF of 0.55mm. 3D printing enables flexible design of monolithic multi-element systems with aspheric surfaces of very short WDs and relative ease of integration., Competing Interests: Disclosures The authors declare that there are no conflicts of interest related to this article.

Three-dimensional (3D) printing technology has evolved tremendously in recent years, but due to stringent requirements on surface finish and limited material selection for optical performance purposes, 3D printing optics is still lagging behind. This paper reports on a quantitative study on the printing process of optical lenses using acrylic and cationic combined commercial hybrid material. By utilizing its unique curing property with digital light process technology, we demonstrate the concept of continuous printing in the top-down light projection setup. Also, an equal thickness and equal arc combo method has been proposed and evaluated to further help smooth the surface finish. Millimeter-level spherical lenses have been successfully fabricated, and their optical performance has also been discussed.

Computer-controlled additive manufacturing (AM) processes, also known as three-dimensional (3D) printing, create 3D objects by the successive adding of a material or materials. While there have been tremendous developments in AM, the 3D printing of optics is lagging due to the limits in materials and tight requirements for optical applicaitons. We propose a new precision additive freeform optics manufacturing (AFOM) method using an pulsed infrared (IR) laser. Compared to ultraviolet (UV) curable materials, thermally curable optical silicones have a number of advantages, such as strong UV stability, non-yellowing, and high transmission, making it particularly suitable for optical applications. Pulsed IR laser radiation offers a distinct advantage in processing optical silicones, as the high peak intensity achieved in the focal region allows for curing the material quickly, while the brief duration of the laser-material interaction creates a negligible heat-affected zone.