Space-based laser communications is a groundbreaking technology that enables better, faster, and more reliable data transmissions than traditional radio frequency technology.
Space-based laser communications is a groundbreaking technology that enables better, faster, and more reliable data transmissions than traditional radio frequency technology.
Laser optics for surgery enable medical professionals to perform ultra-precise, minimally invasive surgical procedures.
Key Takeaways Lithography is crucial for precise, versatile, and efficient microlens array fabrication. It enables complex designs for advanced applications like laser beam shaping. Techniques like gray scale and direct laser writing lithography (DLWL) enhance efficiency and customization. Avantier leverages this technology for high-quality, tailored microlens array production. Lithography is a key technique in microlens array fabrication, and the secret behind the precision manufacturing of many of the world’s highest quality and most innovative microlens arrays. Here we’ll look at just why it is so crucial for microlens array production, and a few of the ways these powerful methods can be used in practice at a world-class optical manufacturing company like Avantier. Microlens arrays have an important place in the modern world, and lithography is one of their most promising fabrication techniques. Why Lithography Even the simplest microlens arrays have specific and stringent manufacturing requirements, such as high uniformity over a large area. For some applications, the requirements are more complex, especially if they must be manufactured on a flexible or curved surface. Lithography is important in microlens array fabrication because it offers: Precision, allowing the consistent, accurate manufacture of well-defined multi-level structures. For instance, lithography is well suited to producing 2 x 2 square centimeter arrays with feature sizes as small as 2 µm. Versatility. A variety of lithography techniques can be used to produce microlens arrays with different symmetries, structures, and sizes. Many lithography methods are also easily customizable, enabling factories like ours to produce arrays that meet our customers’ exact specifications. Efficiency. Lithography is an intrinsically efficient process, and there are some particular methods like DLWL which can be used to pattern large areas quickly for high fabrication speeds. Cost effectiveness. While cost ratios vary depending on the particular lithographic technique used, some techniques such as using transparency films as grey scale masks can decrease manufacturing times and complexity and reduce production costs. Suitability for Advanced Applications. Laser beam shaping and wavefront sensing require complex microlens array designs, and these are made possible with modern lithography techniques. It is important to realize that lithography is not a one-route manufacturing process; a wide variety of techniques and materials are available that enable optical designers to optimize both the manufacturing process and the resulting arrays. An early stage in the MLA design process involves detailed modeling of expected interactions between a particular type of photoresist and propagated light, and different materials for both photoresist and substrate can be selected depending on desired final results. Here we’ll look at two special techniques that can be used to manufacture microlens arrays with non-spherical geometries. A Closer Look: Gray Scale Lithography Manufacturing a non-spherical microlens array using lithography is typically a multi-step iterative process using binary masks and reactive ion etching to produce multi-level structures in photo resist. Using traditional methods, n repetitions of photolithography and careful attention to alignment are required to generate the n-level structures that are designed to serve as analogs of continuous 3D structures. An alternative method that can, in some cases, drastically increase manufacturing efficiency is grey scale lithography. In the place of binary masks, grey scale lithography utilizes grey scale photomasks (halftone chrome masks or high-energy beam sensitive glass masks are two options) to control light intensity. This enables the generation of 3D structures in just one exposure. The masks themselves transfer patterns onto the photoresist without size reduction and thus must be prepared at the appropriate micrometer scale; they can, however, be produced from large-scale transparency films using microlens arrays to reduce the size. A Closer Look: Direct Laser Writing Lithography Another modern lithography technique that shows promise for manufacturing aspheric microlens arrays is DLWL, direct laser writing lithography. This enables flexible design, a customizable filling factoring arbitrary off axis operation for each microlens, and reduces manufacturing complexity significantly. At the same time, it is well suited for large scale manufacturing at high precision levels. A 2022 study using 12-bit direct laser writing lithography reported high fabrication speed, perfect lens shape control, and average surface roughness of less than 6 nm. Lithography for Microlens Array Manufacturing at Avantier Avantier is at the forefront of microlens array manufacturing, and our state of the art equipment and lithography expertise enable us to produce high quality precision microns arrays to our customer’s requirements. Our expert designers can provide you with detailed modeling of light propagation and photoresist interactions, and help you choose the appropriate materials based on your desired outcomes. Contact us today if you’d like more details on our manufacturing capabilities, to schedule a consult, or to place a custom order. References Shiyi Luan, Fei Peng, Guoxing Zheng, Chengqun Gui, Yi Song, Sheng Liu. High-speed, large-area and high-precision fabrication of aspheric micro-lens array based on 12-bit direct laser writing lithography[J]. Light: Advanced Manufacturing 3, 47(2022) Wu, H., Odom, T., and Whitesides,G. Reduction Photolithography Using Microlens Arrays: Applications in Gray Scale Photolithography. Analytical Chemistry, Vol. 74, No. 14, July 15, 2002 3269. Yao, J. and Uttamchandani, D.G. and Zhang, Y. and Guo, Y. and Cui, Z. (2002) One-step lithography for fabrication of a hybrid microlens array using a coding grey-level mask. In: Conference on MEMS/MOEMS – Advances in Photonic Communications, Sensing, Metrology, Packaging and Assembly, 2002-10-28 – 2002-10-29. Yuan, W., Li, LH., Lee, WB. et al. Fabrication of Microlens Array and Its Application: A Review. Chin. J. Mech. Eng. 31, 16 (2018). Related Content
The reflector telescope is unique among telescopes because of its reflective design. Instead of using lenses to refract or bend light to form images, it uses a combination of curved surfaces and flat mirrors to reflect light for imaging.
The Advancements of ultrawide-field OCT in Retinal Imaging and Disease Management Avantier interviewed Dr. Jian, an expert in the field of ultrawide-field optical coherence tomography (OCT). We would like to extend our gratitude to Dr. Jian for his contribution to this discussion. Can you tell us about your path and how you started working on optical coherence tomography (OCT)? I completed my undergraduate degree in optics in Shanghai, China, and then moved to Vancouver, Canada, to pursue my PhD in biophotonics. It was while I was studying there that I learned about OCT and its applications in eye imaging and adaptive optics. Under the guidance of my supervisor, a pioneering researcher in OCT, I had the opportunity to work with various OCT and imaging systems designed for both the anterior and posterior segments of the eye. A few years after earning my PhD in 2014, I was recruited by Dr. David Huang —one of the co-inventors of OCT— to join the faculty at Oregon Health & Science University (OHSU). There, I took part in developing OCT and other eye imaging systems. What challenges did you face in your research? Developing ultra-widefield OCT presents several challenges. The first challenge is the scan duration. The longer the procedure takes, the more uncomfortable a patient becomes. To minimize patient discomfort, a high-speed OCT system that utilizes advanced laser technology is needed. The second challenge involves imaging depth. We adopted a method to process data in real-time using a GPU, which allows us to accurately image the curved structure of the eyeball. The third and most significant challenge was related to optics. We needed components that could provide high-quality, high-resolution imaging, but the existing designs did not meet our specifications. We also experimented with ophthalmic lenses from other imaging modalities, but they lacked the optical quality and performance necessary for our research objectives. Retinal Imaging by OCT (Copyright: Dr. Yifan Jian, OHSU University) How do you collaborate with Avantier? After conducting various studies, we determined that existing ophthalmic lenses were unsuitable for ultra-widefield OCT. There was just one solution: we had to design and manufacture our own custom optics. This process required us to gain a deeper understanding of optical design and optical software in order to develop a high-performance lens system. It was at this time that we discovered Avantier could produce cost-effective and high-quality optical components. Their approach was more streamlined and affordable than the approaches of other companies, which was particularly important for us as we were new to custom lens design. Today our ultrawide field OCT systems are capable of delivering impressive results. They provide high-quality ultra-widefield images that are utilized in clinics for conditions such as diabetic retinopathy and in neonatal intensive care units to screen premature infants for retinopathy of prematurity. Our collaboration with Avantier has broadened the possibilities of ultra-widefield OCT, and the custom optics we incorporated enable our systems to attain high levels of performance in both research and clinical settings. A sample picture of the eyepiece Research on past and future developments in OCT Our ultra-widefield OCT systems have significantly expanded the capabilities of retinal imaging. Handheld and desktop configurations facilitate comprehensive analysis of both the anterior and posterior segments of the eye, with crucial applications for conditions like diabetic retinopathy and age-related macular degeneration. One of the most significant advancements in my lab has been the development of a system that can capture an almost perfect 3D reconstruction of the entire eye in a single scan. This technology is particularly beneficial for managing myopia, allowing us to track changes in the shape of the eye. We also employ ultra-widefield OCT in ophthalmic oncology to accurately measure tumors within the eye. OCT offers extremely detailed structural information and higher resolution than traditional imaging methods like MRI and ultrasound. Increasing imaging speed has been another major focus of our work. We have developed a new system that projects an entire line of light rather than scanning a single point. This innovation allows for parallel image acquisition, significantly improving processing speed. We are also exploring ways to enhance tissue contrast to reveal retinal layers that were previously difficult to differentiate. I believe that speed will be a defining factor for the future of OCT. Commercially available systems are still relatively slow compared to research-grade devices. Faster OCT will facilitate imaging of a larger field of view and enable functional assessments, such as opto-retinal photography, which allows for real-time evaluation of photoreceptor function. In our research, we will continue to explore mechanisms for achieving higher resolution and better contrast, including oxygen saturation mapping. Thoughtful optical design will be critical in pushing the boundaries of what OCT can uncover. One more aspect I would like to highlight is my research on adaptive optics for high-resolution imaging. We have developed a system that iteratively optimizes image quality without the need for a wavefront sensor. This technology has been successfully applied to imaging small animals. My research on retinopathy of prematurity is another area in which we’ve been able to make a meaningful difference. Utilizing ultra-widefield handheld OCT, we have redefined diagnostic criteria for this condition and identified new biomarkers that traditional imaging could not detect. These new criteria show great promise for early diagnosis and treatment. About Dr. Yifan Jian Dr. Yifan Jian is an Associate Professor at Casey Eye Institute specializing in optical imaging. He earned his Ph.D. from Simon Fraser University in 2014 and later joined Oregon Health and Science University (OHSU) to advance OCT technology for ophthalmic imaging, including real-time processing and adaptive optics innovations. Currently, his main research focus is advancing ultrawide-field OCT systems. From Avantier It is an honor to support Dr. Jian’s research as an optical solutions provider. His work has a great impact on the world, advancing science and biomedical technology and providing real value, especially for premature infants and their families. As an optical manufacturer and as a member of society, we are grateful to dedicated individuals like Dr. Jian who
With over two decades of experience in optical engineering and manufacturing, our company specializes in the design and production of high-precision microscope objectives.
A LiDAR sensor for robotics is more than simply another mechanical imaging system. LiDAR, short for Light Detection and Ranging, uses light in much the same way radar uses radio waves— to create a highly accurate, highly reliable map of surrounding objects.
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In today’s rapidly advancing technological landscape, semiconductor manufacturing pushes the boundaries of precision and miniaturization.
Custom optical objectives are crucial for semiconductor manufacturing and inspection, enabling the precision needed for advanced technologies.