Professor Laura Ronchi Abbozzo of the Ronchi Foundation, formerly with the University of Florence, has been organizing the biannual AITA meetings in different cities, primarily in Italy, for the last 30 years. A small group of prominent Italian scientists, mostly working at the National Research Council (or CNR, by its initials in Italian), form the core group of chairs. Participating organizations include the Istituto di Fisica Applicata “Nello Carrara”(IFAC-CNR), the Istituto per le Tecnologie delle Costruzioni (ITC-CNR), the Istituto di Scienza e Tecnologie dell’Informazione “Alessandro Faedo” (ISTI-CNR), and the Istituto di Biofisica (IBF-CNR).

This year the conference was organized once again in Florence, where it all started nearly 30 years ago. The 15th International Workshop on Advanced Infrared Technology and Applications took place from 16 to 19 September 2019, with a total of 54 talks delivered over three days. Their three-page summaries were published in 2019 in MDPI Open-access Proceedings, Vol. 27 (https://www.mdpi.com/2504-3900/27/1).

This special issue is a result of the intention to publish select expanded papers presented at the conference. In the tradition of Applied Optics (AO), the special issue editors invited participation of all practitioners of IR through a published call-for-papers and personal contact. The submission deadline was 15 January 2020, with the accepted papers published fewer than five months later for the 10 June 2020 issue. Most were available online within three to four months of submission.

The journal received 36 manuscripts; of those 20 were accepted upon the strict review process involving two reviewers, as it is customary for journals published by The Optical Society. Approximately two-thirds of the submitted manuscripts were significantly expanded from the conference presentations, and one-third submitted by authors who were not associated with the conference. A handful of manuscripts, subject to demanding reviewer observations, are still in the revision process. The editors anticipate that those papers will be published within the next month or so.

Scientists from Asia, Europe, Australia and the Americas are participating in this compendium. Contributors from Asia come from China, Hong Kong, India, Israel, Korea, Russia, and Thailand. The European countries are represented by Belgium, Germany, and Italy; one author is from Australia, while the Americas participated with papers from Brazil and Mexico.

Today, infrared (IR) technology is being integrated into electro-optical information-processing systems to enhance their usefulness and applicability. Reasons for rapid advances in IR technology are abundant, and quite interesting to contemplate, when compared with the advances in the visual interval [0.38 µm–0.78 µm]. IR is less intrusive to its subjects and more informative because its noise content is often lower. The IR interval includes a rather wide spectral band between the visible and the terahertz (THz) range. The edge of the visible is relatively easy to define: a typical person does not see with his eyes any radiation in IR. The onset of the THz range is defined by the use of different sources, often smaller detectors and, increasingly, by specialized advanced electronics. It is usually assumed to be prevalent beyond a few hundred micrometers.

IR technology and its diverse applications are moving from the novelty stage to useful, practical, real-life applications such as biomedical, non-invasive testing and quality control, and biometrics. We are finding that the algorithms of image processing techniques developed for the visible interval are much more difficult to implement in the ambiguous IR spectral range. We humans have not yet learned to interpret well the IR imagery, so we cannot teach machines to do it for us autonomously. This is leading to development of new algorithms to specifically address the idiosyncrasies of the invisible IR spectral range.

In presenting the advancements in the field of IR in this dedicated issue, we can look with a great deal of satisfaction at the breadth of applications and contributions of IR technology to the well being of humanity. We will continue using IR as an electromagnetic spectrum region, where nondestructive testing may be performed to detect material defects and performance anomalies of both inanimate objects and animate creatures. With continued technology developments, the experimental techniques will likewise become more attuned to ever-smaller dimensions of features under study, including electronic circuits.

Looking through this special issue, we learn that characterization and non-destructive testing of novel materials, ranging from the graphene to metamaterials, require utilization of ingenious new imaging, analytical, simulation, and image processing techniques. We invite all who want to see the future actually taking place to join us at the next AITA meeting in Venice, Italy, in September 2021. Further information will be posted on the conference website as it becomes available (https://www.ronchi.isti.cnr.it).

When AO opened the submission process for this special section, it corresponded to the beginning of a pandemic whose presence today is still increasing in the USA, while hopefully starting to subside in Europe. Covid-19 has temporarily changed our way of life as we are learning of its coronavirus idiosyncrasies, including the manner of its specific transfer between humans and its attack strategy. In this special issue we feature five papers related to the biological and health applications of the IR technology aided by ever more evolving image-processing techniques.

Likewise, we are quite accustomed to the idea that a small vile of our fluid is collected in a medical laboratory then analyzed using diverse analytical tools. In large laboratories, this may be performed routinely within minutes after several cubic centimeters of the blood have been withdrawn, an experience that some of us have not gotten used to, even after innumerable trials. The diagnoses of bacterial and viral infections are much more time consuming. Maybe it takes just a second to take a sample with a swab, though the bacteria or virus still needs time to reproduce to a level that is detectable, usually in about 24 hours.

In these changing times, we need a technique where the presence of a virus inside an individual would be detectable remotely, without collecting body fluids or waiting for the increase in virus concentration. This is what Dr. Maiti and collaborators propose to accomplish in their paper, where they demonstrate and illustrate a technique they developed to analyze bio-fluids in the gas phase. Dr. Maiti is from the Max-Planck Institute for Quantum Optics, Germany. His collaborators Drs. Apolonski, Roy, and Lampe are from the Institute of Automation and Electrometry, Russia, Ludwig-Maximilians Universitity, Munich, and the Technical University of Munich, both in Germany. The authors push the limits of IR spectroscopy of bio-fluids in the gas phase, particularly the features of breath and urine headspace realized with FTIR spectroscopy. They show that aggregate data from different bio-fluids in gas phase can strengthen the diagnostics of the body state and disease.

Another technology development study is concerned with devising techniques where people can continue functioning and working outside the home without adding to the expansion of pandemic. One of the most difficult aspects of the current Covid-19 pandemic is that it is highly contagious. From a physics perspective, it means that the virus must at all cost be kept away from the person who has not yet been infected. At the same time, individuals may be carriers without showing any signs that the virus has already infected them. It is relatively easy for a general population to keep away from a sick person whose very physical aspect represents a warning sign. It is much more difficult to diagnose a carrier who goes about his daily business of living without signaling to the whole world that proximity to him represents a danger.

The need for rapid awareness of the presence of an infected individual was made apparent with SARS and MERS, earlier respiratory diseases. In areas of much personal traffic, including airports, bus and train stations, and public buildings, measures to determine temperature of personnel non-invasively were incorporated. Of course, temperature measurement using IR is quite well established in the laboratory setting. The challenge in an area of dense human traffic includes several additional preprocessing and task-supervisory steps. These include recognizing humans, examining all individuals, and determining their distance, while accounting for other variables. Furthermore, such a system should be economical and, to a high degree, independent of human supervision.

Dr. Somboonkaew with coworkers Drs. Vuttivong, Prempree, Amarit, Chanhorm, Chaitavon, and Porntheeraphat from Photonics Technology Research Team, in collaboration with Dr. Sumriddetchkajorn at National Electronics and Computer Technology Center, all from Thailand, describe temperature-compensated IR-based low-cost mobile platform module for mass human temperature screening. Their mobile platform module called μTherm utilizes a FLIR ONE camera as the visible and thermal imaging cameras. It can simultaneously determine temperature from nine people at a speed of 8 frames/second. Field test operation was performed for four days with 1,170 people, indicating highly promising results of 100% sensitivity, 92.6% specificity, and 92.7% accuracy.

This system is expected to have much use now that social distancing rules have been relaxed in favor of returning to a productive economy and life to which humanity has gotten accustomed.

The third paper in the biomedical applications deals with the important delivery of drugs using porous fibers. Drug delivery to the needed site must be uniform and controlled, with an understanding of how the fiber degrades in time.

Porous fibers for drug delivery and other applications have traditionally been characterized using imaging with the scanning electron microscope (SEM). This method’s shortcomings are that it is only a spot determination of the porosity, is destructive, and requires sample preparation and data processing for the final determination of important parameters.

Drs. Wen, Li, Huang, and Zou from the China Tobacco Company and Sichuan University, China, present a novel method of calculating porosity based on the M44-element of the Mueller matrix. They compare the novel technique against the traditionally employed SEM analysis for the porosity determination of the electrospun fiber. The pore areas of M44 images were extracted by region growing, while the contour parts were obtained by performing morphological operation on pore areas. The porosity calculated by the polarization microscope image is good and consistent with that measured by the SEM. Their results promote practical application of electrospun porous fibers in the early stage of screening a large number of porous materials in the field of biomedicine.

The drug delivery, both during the prescribed time period and in the precise quantity, is of critical importance during the oncological treatment. Sometimes, a surgery is required, as in the one-third of breast cancer patients who undergo uni- or bilateral mastectomies, and the one of seven who undergo reconstruction surgery. Often in such cases, the patient’s proper skin is taken from the abdominal area, or to use the medical jargon, an autologous free DIEP (deep inferior epigastric artery perforator) flap. In exceptional cases, the transplanted tissue lacks sufficient blood supply. This may result in cell injury, cell death, and tissue necrosis. There exist several techniques to monitor the health of the transplanted skin, but they are quite expensive, invasive, and cumbersome to use.

Five scientists from the University of Antwerp and the Antwerp University Hospital in Belgium are proposing to evaluate pulsed IR thermography (PIRT) as the imaging tool to assess the blood delivery to the transplanted skin. Drs. Verstockt, Thiessen, Cloostermans, Tjalma, and Steenackers form the multidisciplinary team of scientists, plastic surgeons and oncologists to carry out such a study in-vivo. Their report argues convincingly for the implementation of the thermographic instrumentation to assure quality of surgical procedure DIEP flap.

Breast cancer is one of the most common cancers affecting the world population, especially women. Early detection of the disease is essential to improve the treatment outcome and patient recovery. The traditionally established techniques of x-ray and sound are often complemented by the thermography. IR thermography has emerged as a promising technique for the diagnosis of the disease due to its low cost, and its use of benign radiation. Furthermore, it has been reported that it provides good results when applied in young women. It detects hot spots, or at least tissue with slightly elevated temperature, due to increased metabolism rate. The challenges in interpreting the thermographic images of the breast region include the vascularization that is different from one patient to another and between different times, even for the same patient.

Data processing is of high importance in IR non-invasive testing and image evaluation. The convolutional neural network (CNN) technique is one that was well received for decision-making within the visible imagery. NNs are particularly helpful when a small number of the outcomes are expected and much data is available for training. It is often convenient to train the network on the fresh imagery to establish decision-making paths. The CNN is most commonly applied in the analysis of visual imagery, incorporating deep learning.

Four researchers from the Federal University of Uberlandia in Brazil, Drs. Chaves, Gonçalves, Albertini, and Fernandes (who is currently at the Fraunhofer Institute for Nondestructive Testing, Germany), collaborated with Dr. Lee from the Sejong University and Dr. Jeon from the Incheon National University, both in Korea. They evaluated the transfer learning of pre-trained CNNs applied to breast cancer detection on IR images. During the network training, they use transfer learning of five CNN architectures. Those are AlexNet, GoogLeNet, ResNet-18, VGG-16, and VGG-19. Their results show a great potential of using deep learning techniques combined with the IR images in the aid of breast cancer diagnosis.

When the number of variables is very large, NNs offer a systematic procedure of data classification. When the data is furthermore unstructured and unlabeled, deep learning is often used. This specialized field is a subset of machine learning in artificial intelligence that incorporates networks capable of unsupervised learning. It tends to include many hidden layers and works on so-called big data.

From the biomedical applications of IR, we transition to energy exploration using deep learning. Well logging is an example of such big data, collected worldwide in search of economically produced energy resources. Well logging is the practice of making a detailed record (a log) of the geologic formations that the exploration borehole has penetrated. Well logging is often performed in boreholes drilled for the oil and gas search in the studies to determine the economic feasibility of exploiting an energy source. The log may be based on physical measurements made by instruments lowered into the well.

Four authors from China, Drs. Song, Wu, Li, Yang, and Dr. Guo from Australia collaborated in developing a system for deep learning in quantitative analysis of FTIR spectrum of logging gas. The first three authors are from the TianGong University, while the fourth one is from the Tianjin University, both institutions in China. Dr. Guo works at the University of Wollongong.

IR spectral analysis can perform fast and non-destructive detection of gas. It has been widely applied in the oil field of chemical industry. For this work, the authors designed the Fourier transform infrared spectroscopy (FTIR) logging gas detection system for the collection of IR spectral data. They also built the multi-channel gas-mixing device to configure experimental gas samples. The mud logging gas samples used in this work are composed of the logging gas actually collected at the logging site and the gas samples configured by the laboratory simulated logging site environment.

A total of 75 gas samples with different concentration mixtures are configured. This work studied the quantitative analysis technology of IR spectrum based on deep learning. The experimental results show that the quantitative analysis model of logging gas presented in this work can reach 100% recognition accuracy for elemental gas. The attained accuracy rate of mixed-gas spectral identification is 98%. The findings indicate that the IR spectrum logging gas detection model based on deep learning can quickly and accurately perform quantitative analysis of logging gas.

We are still studying materials, but we now move from the near IR to address how new devices and applications are incorporating novel materials in far IR. Three papers deal with the sophisticated future of IR sensing.

Dr. Dmitriev at the Federal University of Pará, and Drs. Melo and Castro at the Federal Rural University of Amazônia, both in Brazil, studied graphene-based multifunctional three-port THz and long-wave IR components. They proposed and analyzed two graphene-based T-shaped multifunctional components for THz and far IR regions. The first component is a stand-alone T- junction that functions as the divider-switch over more than one (1) octave frequency interval.

The second component can serve as a divider, a switch, or a dynamically controllable filter. This T-junction presents a circular graphene resonator and three graphene waveguides, with surface plasmon-polariton waves connected frontally to the resonator. The resonator may be adjusted to work with dipole, quadrupole or hexapole modes. The graphene elements are deposited on a ${\rm SiO}_2$ (silica) and Si (silicon) two-layer substrate. The electrostatic field provides dynamical control and switching of the component. Simulations show adequate performance for the ON and OFF positions.

Metamaterial perfect absorbers (MPA) have been proposed and demonstrated for frequencies ranging from microwave to THz, IR, and visible. The top structure is often constructed from material that is sensitive to environmental effects. When it gets easily damaged, its performance decreases with time.

Four Indian authors, two from the Indian Institute of Technology, Drs. Pradhan and Ramakrishna, collaborated with Dr. Achanta, from the Tata Institute of Fundamental Research, and Dr. Agarwal, from Instruments Research and Development Establishment. They simulated, fabricated and demonstrated performance enhancement of an MPA by coating its top with a dielectric layer of precisely specified thickness.

The trilayer absorbing structure consisting of metal-dielectric-metal is coated with a protective layer of a transparent dielectric. The interference effects between the light reflected from the top surface of the protective layer and the structured metallic layer of the MPA give rise to enhanced absorption that is highly dependent on the thickness of the protective layer. The capacitive loading due to the increased dielectric permittivity of the surroundings results in a red shift of the resonance. This effect was verified experimentally using the tri-layer structure of Al/ZnS/Al (aluminum/zinc sulfide/aluminum). The ZnS protective layer simultaneously modulates the absorption in the structure and creates a safe packaging layer for the structure, protecting it from harsh environments in field applications.

Three-dimensional scanning and object and/or its shape identification has been of great interest within the last few years. It is even used for facial identification (as in biometric access) in cities with cameras set at busy street corners and other locations, as in Great Britain. Similarly for its traditional use in industrial control, visible light is not efficient in preforming this task. The ambient visible illumination represents noise during the daytime, and illuminating LEDs or lasers are too bright for illuminating human faces. Thus, an operation of these devices should preferably be translated into the IR portion of the electromagnetic spectrum.

Four Chinese researchers at the Shenzhen Institutes of Advanced Technology, Drs. Ye and Chang, also associated with the University of Chinese Academy of Sciences, collaborated with Drs. Song and Zhao, affiliated with the Chinese University of Hong Kong, to develop an accurate IR structured light sensing system for dynamic 3-D acquisition.

Their high resolution and high accuracy scanning system adopts the Gray code, combined with stripe shifting as the strategy for 3-D acquisition and coding. The algorithm is implemented in parallel via the graphic processing unit. Their newly designed and built system captures dense and high precision 3-D model sequences with a speed of nearly 30 Hz. They describe various experiments and compare the performance of the novel system with commercially available units.

They performed several experiments to verify the feasibility and accuracy of their IR structured light sensing system. They report that it compares favorably witht the available commercial devices. The calibration system receives much credit for the excellent performance.

For those of us in the IR field, it is gratifying to know that IR imaging is performing better at object and facial identification than visible technology. Of course, improved system performance is a consequence of the advanced developments in components and technology. We include three papers dealing with such advances.

Ultra-short pulses at 2 µm have important applications and development prospects in many fields, including spectroscopy and the use of lasers in medicine. They can be formed from mode-locked lasers, achieving pulse durations around 20 ps. However, ultra-short mode-locked fiber lasers require an improved design to achieve required stability.

Pulse compression is an alternative method to generate ultra-short pulses. A cascaded higher-order soliton compression scheme has been proposed to achieve high quality pulse compression while generating relatively small pedestal energy. For example, a two-stage second-order soliton gets a compression factor of 19.7 with the pedestal energy of 18.8%.

Drs. Wang and Li at Peking University described theoretical performance, fabricated, and characterized cascaded single mode fibers for higher-order soliton compression at 2 µm. They investigate the compression performance for the initial input pulse width from 1 ps to 50 ps. For the initial third-order soliton of 10-ps width, a compression factor of 75.7 was been generated with the pedestal energy of less than 50%.

The ability to tailor the properties of materials and devices for their performance in the IR is most important in the detector performance, especially for the noise minimization at elevated temperatures. Detector improvements in two spectral regions are represented in this compendium.

Polish researchers Drs. Hackiewicz, Kopytko, Rutkowski, and Martyniuk from the Military University of Technology joined with Dr. Ciura at Rzeszow University of Technology to investigate the influence of GaAs (gallium arsenide) and GaSb (gallium antimonide) substrates on detection parameters of InAs/GaSb (indium arsenide) superlattice based mid-IR interband cascade photodetectors. They are particularly interested in studying the effects of using optical immersion on the optical properties of the devices.

They report that the detectors grown on GaAs exhibit better detection parameters at room temperature. At lower temperatures the misfit dislocations become increasingly more important, resulting in performance deterioration of this combination. The performance of detectors grown on GaSb at reduced temperatures is improved.

The key area of technology development necessary for widespread use of IR vision is camera operation at increasingly higher temperatures, without the increase in dark current and image noise. Majority carrier depletion has been proposed as a method to suppress the dark current originating from quasi-neutral regions in HgCdTe (mercury cadmium telluride) IR focal plane array detectors. However, a very low doping level is usually required for the absorber layer, a task quite difficult to accomplish in actual practice.

A team of four Italian scientists, Drs. Vallone, Goano, Bertazzi, and Ghione, collaborated with four German researchers at AIM Infrarot-Module GmbH, Drs. Hanna, Eich, Sieck, and Figgemeier, to address the problem of dark current. The Italian collaborators are authors associated with the Politecnico di Torino and IEIIT-CNR who report on the constraints and performance tradeoffs in Auger-suppressed HgCdTe focal plane arrays. Simulations were performed on a small, $5 \times 5$ pixel sample, to determine detector performance under varying conditions of doping concentration and temperatures.

They found that the high-temperature operation has quite stringent requirements on the reduction of residual doping, while a decrease in the absorber thickness helps only moderately in the dark current minimization. Under illumination conditions, inter-pixel crosstalk is only slightly diminished by a decrease in temperature or absorber doping in the performance intervals under investigation. Thinning the absorber was found to reduce effectively pixel crosstalk.

The last group of papers deals with thermography, one of the most popular applications of IR to non-destructive, non-invasive testing, to remotely and non-invasively detect back surface or depth defects. This technique is continually improving its applications, in quality of measurements, and in the development of theory in support of experimental work.

Seven Italian scientists have been investigating the interesting question of how to make visible defects in the archaeological glass. Drs. Melada, Ludwig, Micheletti, Orsilli, Gargano, Grifoni, and Bonizzoni at the State University of Milan describe the visualization of the defects in glass using pulsed thermography. They endeavor to determine the conservation status of archaeological glass. The knowledge about how valuable artifacts degrade upon passing centuries of burial can be of great archeological, historical, technological, and material relevance.

They evaluated the potential of using pulsed thermography to map the presence of flakes in archaeological glass. Initially, the tests were carried out on glass mock-ups with surface defects. Once the technique was proven, it was transferred on the precious archaeological artifacts. This was achieved by comparing different heating setups and signal processing algorithms. The authors are satisfied that this procedure may be used for other antique glass objects subject to unconventional historical treatment.

One of the ever-present concerns about the use of increasingly smaller electronics packaged in restricting volumes is that even thinnest devices generate heat due to resistance. Excessive heat makes the devices inoperative, as we all experience when our laptops refuse to function after prolonged use. Even worse, the overheating sometimes results in permanent damage. The thermal inspection of integrated electronic and photonic circuits is an ideal subject of inspection for thermography. The IR camera precisely detects damaging heat source.

Scientists from the Institute of Technologies for Communication, Information and Perception, Drs. Hussain, Imran, Serafino, and Ghelfi, collaborated with a team from the Institute of Science and Information Technologies of Italy’s National Research Council, Dr. Jalil, Pascali, and Moroni, to assess and detect the circuit vulnerability to generate excessive heat. Conventional standards in the high temperature operating life tests are not suitable for operating life prediction of photonic components, owing to their functional dependence on thermo-optic effect.

By applying image fusion using affine transformation on multimodal acquisition, the authors demonstrated that it is possible to accurately locate the heat centers along with spatial information. The thermographic technique offers a reliable automated identification of heat spots within a circuit or system. For the first time, the reliability testing is extended to a fully functional microwave photonic system using conventional IR thermography.

In flash-pulse thermography, either a laser source or lamps may be used to deposit the requisite amount of heat during a short pulse on the sample.

Researchers from three institutes of the National Research Council in Italy, Drs. Ferrarini, Bortolin, and Bison from the Institute of Technology of Construction, Dr. Cadelano, of the Institute for the Science of the Atmosphere and Climate, and Dr. Finesso, from the Institute for Electronics and Information Engineering, developed a new method of applying the laser flash method. This is actually an established procedure to determine the thermal diffusivity of a wide variety of materials.

Sometimes, though, it is necessary to reduce the irradiation heat load in the laser flush-pulse experiment. This could happen, for example, when characterizing materials with high thermal capacity, or investigating thick samples, or due to the need to decrease the irradiating power due to the surface sensitivity. The authors propose a new laser flash control and data acquisition system that is capable of repeatedly applying the laser impulse and measuring the specimen thermal response. With the average of several measurements, a decrease in the noise may be obtained when working with low power inputs.

The Czech researchers Drs. Muzika, Švantner, and Moskal from the University of West Bohemia present a procedure to interpret measured surface temperature data to identify open spaces on the sample backside using flash-pulse thermography. Authors introduce a time-power transformation to minimize data storage. In exchange some parameters must be determined by numerical adjustment.

The method is based on the transformation of the measured thermal response using a power function of time. This technique is an extension of the reference-free dynamic thermal tomography, introduced by Dr. Vladimir Vavilov. The authors transform the front-surface temperature evolution, as measured by the IR camera in a flash-pulse excitation experiment. The function parameters are sensitive to any preprocessing and noise elimination procedures.

Drs. Švantner, Muzika, and Houdková, who is also from the same research center in the Czech Republic, applied the technique of power transformation to the inspection of coatings thickness. A flash pulse thermographic testing was applied to thermally sprayed coatings to determine their thickness uniformity. Different evaluation methods were analyzed and compared. The authors conclude that a time-power transformation method is highly suitable for the quantification of the inspection results.

Members of the IR community, including researchers publishing in this field, as well as the editors who had the privilege of assembling this collection of papers, would like to express our gratitude to Dr. Ronald Driggers, the Editor-in-Chief of Applied Optics for inviting us to compile the papers in this special feature, Advanced Infrared Technology and Applications 2020.

Furthermore, we wish to acknowledge the invaluable assistance of Ms. Nicole Williams-Jones, Senior Journal Coordinator for Applied Optics. Nicole performed a wonderful job of ensuring the very short submission-to-publication time. She assisted along the way with keeping peer review on track, sending papers out for review, and reminding the editors of pending tasks. We want to express our appreciation to Mr. Dan McDonold, OSA Editorial Director and Mr. John Long, for providing guidance in preparing the call-for-papers and for explaining the established editorial procedures at Applied Optics.

Additionally, we are grateful to all the reviewers who took time from their busy schedules to provide constructive feedback to the authors. We appreciate the efforts that the authors have made in preparing the manuscripts and responding to the suggestions of the editors and reviewers in making their work more understandable to the readership of Applied Optics.

Finally, we thank Ms. Cristina Kapler, senior managing editor of Applied Optics, whose mastery of language is unsurpassed, for finely tuning the final subtle improvements to the introduction! The guest editors who often recommend that the authors ask a native English speaker to look over their manuscript one more time are the first to follow their own advice!

This collection of papers on IR is dedicated to Professor (Emeritus) Dr. Laura Ronchi Abozzo who founded the AITA conferences, published most of its proceedings and provided the soul to the core group of its scientists. We are including a short biography of this remarkable scientist and humanist on the occasion of her 90th birthday.

Laura Ronchi Abbozzo, the uncomparable professor at the University of Florence, now retired, is a scientist and physicist, who serves as a promoter of science and mentor to others. She has dedicated her professional life to the study of electromagnetic fields. A former director of research for CNR, the Italian National Research Council, Laura has been organizing international scientific conferences on electromagnetic waves for over 40 years. Furthermore, for over 30 years she has been the editor-in-chief of the refereed scientific journal, Atti della Fondazione Giorgio Ronchi. She has also edited and published scientific books for the Ronchi Foundation.

Laura has dedicated her research to dual-use technology, in efforts to employ state-of-the-art technical achievements to better the living conditions of the civilian population, pioneer new medical applications as well as search and rescue endeavors. She has also been actively involved in social, cultural and civic activities.

Prof. Ronchi Abbozzo was born in Florence, Italy, in 1929. Her father, Prof. Vasco Ronchi, was the well-known optical scientist and inventor who founded the Italian National Institute of Optics. Her mother, Dr. Edda Ronchi Suckert, was one of the first women in Italy to be granted a university degree in mathematics.

Prof. Ronchi Abbozzo earned a degree in physics at the University of Florence in 1950, at the age of 21. She was conferred a doctoral degree there in 1956, working under mentorship of Professor Nello Carrara. She taught at the University of Florence from 1961 to 1996, and continued her career at the CNR Microwave Institute in Florence, remaining there for the rest of her professional life. She also collaborated on diverse projects with researchers at Consorzio CREO, particularly with Dr. Carlo Corsi.

As a member of the International Commission for Optics, she worked to include developing countries as members and contributors. Laura Ronchi Abbozzo is one of those one-in-a-million professional women who use their power and influence to promote other women. In her conferences, women were regularly invited to deliver keynote presentations and function as session chairs and program reviewers. Early on, as Editor-in-Chief, she invited women to sit on the editorial board of the refereed scientific journal Atti della Fondazione Giorgio Ronchi.

She was particularly interested in promoting civilian and pacific use of optical technologies. Since 1992, together with a select group of international scientists, she has organized an annual (later bi-annual) conference on AITA in Europe, Canada and America. Within these very popular and successful conferences, which were usually hosted by a local university or a CNR institute, she chose to organize lively meetings that required small registration fees.

She was interested in attracting scientists from Eastern European countries who often lacked funds for travel. Under Laura’s leadership, Fondazione Giorgio Ronchi published proceedings of the first few meetings. Recently, Applied Optics dedicated a special section to IR that included select papers from the preceding AITA conference.

Within the last 30 years, Prof. Ronchi Abbozzo has also dedicated herself to several social projects, focusing primarily on the scientific education. She is a member of the national committee of Libera, the Italian association that promotes outreach activities. She continues to be actively involved in work to help migrants and refugees.

We are hoping that Laura continues her productive life for many years!

Prof. Laura Ronchi Abbozzo. (Photo by Prof. Dr. Margherita Abbozzo Heuser, 2020.)