Optical Design Research Articles

Current Evidence for a New Surgical Technique for Scleral Fixation: The Implantation of a Carlevale Lens, a Systematic Review.

Background: The Carlevale lens (FIL SSF, Soleko IOL Division, Italy) is a new lens for suture-less scleral fixation. This paper aimed to systematically review articles on this lens, the surgical techniques used for its implantation, complications and outcomes. Methods: This systematic review was performed following the PRISMA guidelines. The search string used was "Carlevale" AND "scleral fixation" from inception until March 2024. For completeness, either case-control studies, case reports or case series written in English were included. The authors used the Newcastle-Ottawa scale for the case-control studies and the JBI Critical Appraisal Checklist for case reports and case series. Results: Twenty-nine articles were included. Scleral fixation with Carlevale lens can be performed by creating scleral flaps or, alternatively, by using scleral pockets. The two sclerotomies must be diametrically opposed, and are preferably created by 25-gauge trocars. A pars plana vitrectomy should be performed every time, and the design of the lens should be suitable for self-anchoring to the sclera; the most accredited strategy to achieve this is to avoid scleral sutures. There were only a few intraoperative and postoperative complications reported; vitreous hemorrhages were the most frequent intraoperative events, while the most relevant postoperative complications were vitreous hemorrhages, cystoid macular oedema and transient variations in the intraocular pressure. Excellent results have been obtained in terms of BCVA, IOL centration and stability, mean intraocular pressure, postoperative spherical equivalent, separation between anterior and posterior chamber and the distance of the IOL from anterior chamber structures. Conclusions: The foldable hydrophilic design of the Carlevale lens has shown good effectiveness, IOL stability and few intra and post-operative complications.

Creating advanced photonics AI assistants

AbstractThe AI assistants that have emerged in the past couple of years open up new domains of knowledge, allowing us to be educated and guided in many new and versatile domains. However, for domain experts such as optical designers, scientists, and photonics engineers, they often have limitations in their information accuracy and scope. 3DOptix has developed a dynamic approach to overcome these limitations that enables the creation of a proficient optical design copilot. This copilot assists experts in every step of the design process, including conducting precise calculations, searching for components, and simulating actions.

7‐3: Analysis of a 1.2‐in. 4k2k LCOS Display Phase Modulator for Holographic Display Applications

This developed 1.2‐inch 4K2K LCOS with 76.0 lp/mm spatial resolution can still achieve high phase accuracy and obviously enlarge field‐of‐viewing (FOV) angle compared with previous 0.55‐inch 2K1K LCOS. The holographic image quality within phase‐only LCOS not only can be improved by using higher phase accuracy and compensation technologies, but also can realize the real 3D imaging into near‐eye displays to avoid the VAC phenomena. In addition to, the holographic 4K2K LCOS (26.6mm x 15.8mm) optical design can achieve lighter optical engine and reconstructed square (26.6mm x 26.6mm) image per eye, so that it has advantages of more feasible driving condition and cost competition. As high‐speed technologies of display electronics, liquid crystal, and optical algorithm were gradually mature, the above 1.2" phase‐only LCOS with both high pixel resolution and smaller pixel pitch will be another choice into the VR & MR headsets utilized video see‐through (VST) method. Meanwhile, the 1.2” 4K2K LCOS with enhanced FOV can be alternative scheme for AR glasses using optical see‐through (OST) method before the trade‐off between volume, brightness, and FOV angle are resolved.

39‐3: Invited Paper: Kirameki Display: Technical Approaches to Represent Real Texture with Light Fields

We have developed a “Kirameki display” that can represent a real texture of materials. (“Kirameki” means a shining/glittering sense in Japanese.) In addition, we have investigated an improvement of “texture representation” by optimization of both an optical design and a software algorithm. Lastly, we discuss the future technical fields for texture representation on displays.

International trends in rigid contact lens prescribing (2000–2023): An update

PurposeRigid contact lenses have an important role in contact lens practice. The purpose of this work is to update earlier surveys by describing global trends in rigid lens fitting between 2000-2023. MethodAn annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023. Data relating to 342,500 fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of rigid lens fitting, defined as the fitting of any design of a contact lens manufactured in a rigid material. ResultsOverall, rigid lens prescribing increased slightly over time, from 14.2 % of lens fits in 2000 to 15.2 % in 2023 (p < 0.0001). However, post-hoc analysis shows that the change over time is best described as a decline between 2000 and 2012, followed by a steady increase subsequently. There were significant differences in rigid lens prescribing between countries (p < 0.0001). The difference between the percentage of males fitted with rigid lenses, as a proportion of all contact lenses (12.7 %), and females (12.0 %) is significant (p < 0.0001), although not clinically meaningful. Rigid lens wearers are older at fitting than soft lens wearers (38.7 vs 31.3 years, respectively) (p < 0.0001). Analysis of 5,994 rigid lens fits prescribed currently (2019–2023) were categorised as: corneal sphere – 30 %; scleral and corneo-scleral – 28 %; corneal myopia control/orthokeratology – 21 %; and corneal complex (including toric, multifocal and monovision) – 16 %. ConclusionThere has been a slight increase in rigid lens fitting during the second decade of this century. This increase is apparently due to a ‘repurposing’ of rigid lenses, with the growth of scleral/corneo-scleral and myopia control/orthokeratology lens fits essentially replacing conventional spherical corneal lens fits.

Assessment of the performance of fibre optic sensor designs based on two FBGs

The paper presents, and compares the performance of, two optical sensing systems each based on a combination of two fibre Bragg gratings (FBGs) and where a simple measurement of transmitted or reflected power provides an alternative to specialist interrogators. In both configurations one of the FBGs acts as a reference whilst the other is used as the measuring element. It is shown that using FBGs with wide spectra results in higher dynamic range. The measurement of strain is used to demonstrate the behaviour of the proposed sensing systems. The performance of the two systems is compared experimentally and discussed with the insight of the simultaneous measurement of the spectra reaching the detector.

83‐3: Inverse Design of Liquid Crystal Phase Modulators for 2D/3D Switchable Display Based on Deep Learning

The fringe field effect in liquid crystal (LC) devices can cause pixel crosstalk issues. Therefore, LC devices with multiple electrode structures require multiple calibrations to achieve an approximate distribution of the target phase modulation. At the same time, optical inverse design based on data‐driven algorithms is also a highly popular topic. This article introduces a deep‐learning approach to realize inverse phase modulation in LC devices. By adopting the deep learning method for inverse phase modulation in LC devices, can effectively alleviate the problems caused by fringe field effects and achieve more precise and accurate phase modulation distribution.

International trends in daily disposable contact lens prescribing (2000–2023): An update

PurposeDaily disposable contact lenses offer numerous benefits in terms of ocular health and wearer convenience. The purpose of this work is to update earlier surveys by describing global trends in daily disposable lens fitting between 2000 and 2023. MethodAn annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023, inclusive. Data relating to 265,106 daily wear soft lens fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of daily disposable lens fitting. ResultsOverall, daily disposable lens prescribing increased over time, from 17.1 % of daily wear soft lens fits in 2000 to 46.7 % in 2023 (p < 0.0001). There were significant differences between countries in daily disposable lens prescribing (p < 0.0001), and between the percentage of males fitted with daily disposable lenses, as a proportion of all daily wear soft lenses (37.2 %), compared to females (35.2 %) (p < 0.0001). Daily disposable lens wearers are slightly younger at fitting than reusable soft lens wearers (31.0 vs 31.2 years, respectively) (p < 0.0001), although this difference is not clinically meaningful. Analysis of 50,240 daily wear soft lenses fitted recently (2019–2023) were found to be prescribed for the following replacement frequencies: daily – 47 %; monthly – 42 %; 1–2 weekly – 9 %; and ≥3 monthly – 2 %. ConclusionThere has been a substantial increase in daily disposable lens fitting throughout the first 24 years of this century. The gradual nature of this increase is commensurate with the staged introduction of daily disposable lens designs and expanded parameter ranges over the survey period.

35‐2: Multispectral Pancharatnam‐Berry Phase Liquid Crystal Lens and Its Aplication in AR Displays

Pancharatnam‐Berry (PB) phase liquid crystal (LC) lenses show attractive benefits in optical systems because of their high efficiency, compact size and polarization‐dependent behavior. However, as a kind of diffraction‐based devices, PB LC lenses suffer from chromatic dispersion, which limits their applications in multi‐wavelength imaging systems. In this paper, we demonstrate a multispectral PB LC lens design to overcome this issue. An active multispectral PB LC lens has been fabricated and characterized. It can focus different wavelengths at the same distance so they are expected to solve the chromatic dispersion problem in the multi‐wavelength display system and other broadband optical systems.

27‐1: Flat‐based Double Path Pancake Optics to Improve Productivity

We proposed highly light efficient pancake Head Mounted Display (HMD) optics named “Double path pancake optics” last year, which has 1.8 times higher light efficiency than conventional one.While maintaining such high optical efficiency, this year, we have improved its productivity by replacing curved Reflective Polarizer (RP) with flat one. To realize a structure with flat RP, we have simulated optical concepts and finally found appropriate design. According to our optimized optical design, 25.5 mm thickness with 90 deg Field Of View (FOV) was realized and we have successfully made the prototype and confirmed that the high image quality can be displayed and optical properties are almost the same as our previous one with curved RP.

Coaxial Bright and Dark Field Optical Coherence Tomography.

To improve the signal collection efficiency of Optical Coherence Tomography (OCT) for biomedical applications. A novel coaxial optical design was implemented, utilizing a wavefront-division beam splitter in the sample arm with a 45-degree rod mirror. This design allowed for the simultaneous collection of bright and dark field signals. The bright field signal was detected within its circular aperture in a manner similar to standard OCT, while the dark field signal passed through an annular-shaped aperture and was collected by the same spectrometer via a fiber array. This new configuration improved the signal collection efficiency by ∼3 dB for typical biological tissues. Dark-field OCT images were found to provide higher resolution, contrast and distinct information compared to standard bright-field OCT. By compounding bright and dark field images, speckle noise was suppressed by ∼ √2 . These advantages were validated using Teflon phantoms, chicken breast ex vivo, and human skin in vivo. This new OCT configuration significantly enhances signal collection efficiency and image quality, offering great potential for improving OCT technology with better depth, contrast, resolution, speckles, and signal-to-noise ratio. We believe that the bright and dark field signals will enable more comprehensive tissue characterization with the angled scattered light. This advancement will greatly promote the OCT technology in various clinical and biomedical research applications.

Gain variations as induced by the diffuse night sky background: the ASTRI-Horn experience

ASTRI-Horn is the prototype of the nine telescopes that form the ASTRI Mini-Array, under construction at the Teide Observatory in Tenerife (Spain), devoted to observe the sky in the 1–200 TeV energy band. It adopts an innovative optical design based on a dual-mirror Schwarzschild-Couder configuration, and the camera, composed by a matrix of monolithic multipixel silicon photomultipliers (SiPMs) is managed by ad-hoc tailored front-end electronics based on a peak-detector operation mode. During the Crab Nebula campaign in 2018–2019, ASTRI-Horn was affected by gain variations induced by high levels of night sky background. This paper reports the work performed to detect and quantify the effects of these gain variations in shower images. The analysis requested the use of simultaneous observations of the night sky background flux in the wavelength band 300–650 nm performed with the auxiliary instrument UVscope, a calibrated multi-anode photomultiplier working in single counting mode. As results, a maximum gain reduction of 15% was observed, in agreement with the value previously computed from the variance of the night sky background level in each image. This ASTRI-Horn gain reduction was caused by current limitation of the voltage supply. The analysis presented in this paper provides a method to evaluate possible variations in the nominal response of SiPMs when scientific observations are performed in the presence of high night sky background as in moon conditions.

Integrated optical waveguides for quantum photon gates at a wavelength of 810 nm

Subject of study. The optical losses in waveguides designed for creating quantum photon gates at a wavelength of 810 nm were investigated. Aim of study. The aim of the study was to create integrated optical single-mode waveguides for quantum photon gates at a wavelength of 810 nm and to estimate optical losses acceptable for maintaining the necessary degree of photon-pair entanglement. Method. The waveguides were manufactured through thermal diffusion of titanium ions into a substrate composed of an X-slice of nominally pure lithium niobate (LiNbO3). Optical losses were estimated by experimentally measuring the loss per unit length of the waveguide. Optical radiation was coupled into and out of the waveguide using fiber segments, with one end connected and the other cleaved. A drop of immersion liquid was applied between the cleaved fiber and waveguide end, and measurements were performed for both polarization modes. Main results. Six groups of samples were produced, each containing waveguides with strip widths of d=3.0, 2.0, and 1.5 µm. The measured optical losses in the manufactured waveguides indicated that those with a titanium strip width of d≈3 µm exhibited the lowest losses. The estimated minimum optical losses for transverse magnetic and transverse electric polarization were approximately 0.20–0.25 and 0.1 dB/cm, respectively. Practical significance. The waveguides manufactured with a strip width of approximately 3 µm can be used to create quantum photonic gates in an integrated optical design. The chosen wavelength of 810 nm offers potential for near-future development of photonic gates, as one of the most accessible methods for generating entangled photon pairs involves using a 405-nm laser followed by wavelength doubling through a nonlinear beta-barium borate crystal.

A science-driven approach to optimize the design for a biological small-angle neutron scattering instrument

Biological small-angle neutron scattering (SANS) instruments facilitate critical analysis of the structure and dynamics of complex biological systems. However, with the growth of experimental demands and the advances in optical systems design, a new neutron optical concept is necessary to overcome the limitations of current instruments. This work presents an approach to include experimental objectives (i.e. the science to be supported by a specific neutron scattering instrument) in the optimization of the neutron optical concept. The approach for a proposed SANS instrument at the Second Target Station of the Spallation Neutron Source at Oak Ridge National Laboratory, USA, is presented here. The instrument is simulated with the McStas software package. The optimization process is driven by an evolutionary algorithm using McStas output data, which are processed to calculate an objective function designed to quantify the expected performance of the simulated neutron optical configuration for the intended purpose. Each McStas simulation covers the complete instrument, from source to detector, including realistic sample scattering functions. This approach effectively navigates a high-dimensional parameter space that is otherwise intractable; it allows the design of next-generation SANS instruments to address specific scientific cases and has the potential to increase instrument performance compared with traditional design approaches.

Improvement of optical wave propagation simulations: the scaled angular spectrum method for far-field and focal analysis

In the field of optics, accurately simulating wave propagation is essential for both theoretical insights and practical applications. This study introduces the scaled angular spectrum method (Sc-ASM) for simulating far-field and focal patterns, overcoming the limitations inherent in the standard angular spectrum method (ASM) by allowing variable sampling intervals between source and observation planes. Comparative analysis with the Rayleigh–Sommerfeld integral demonstrates Sc-ASM's superior accuracy in estimating the far-field patterns of beams with complex phase structures. Our results underscore Sc-ASM’s potential to set a new benchmark in optical simulations, significantly advancing optical system design and the study of wave propagation.

AI-Based Metamaterial Design.

The use of metamaterials in various devices has revolutionized applications in optics, healthcare, acoustics, and power systems. Advancements in these fields demand novel or superior metamaterials that can demonstrate targeted control of electromagnetic, mechanical, and thermal properties of matter. Traditional design systems and methods often require manual manipulations which is time-consuming and resource intensive. The integration of artificial intelligence (AI) in optimizing metamaterial design can be employed to explore variant disciplines and address bottlenecks in design. AI-based metamaterial design can also enable the development of novel metamaterials by optimizing design parameters that cannot be achieved using traditional methods. The application of AI can be leveraged to accelerate the analysis of vast data sets as well as to better utilize limited data sets via generative models. This review covers the transformative impact of AI and AI-based metamaterial design for optics, acoustics, healthcare, and power systems. The current challenges, emerging fields, future directions, and bottlenecks within each domain are discussed.

Optical design of longwave infrared image mapping spectrometer

Optical design of longwave infrared image mapping spectrometer

All-optical complex field imaging using diffractive processors.

Complex field imaging, which captures both the amplitude and phase information of input optical fields or objects, can offer rich structural insights into samples, such as their absorption and refractive index distributions. However, conventional image sensors are intensity-based and inherently lack the capability to directly measure the phase distribution of a field. This limitation can be overcome using interferometric or holographic methods, often supplemented by iterative phase retrieval algorithms, leading to a considerable increase in hardware complexity and computational demand. Here, we present a complex field imager design that enables snapshot imaging of both the amplitude and quantitative phase information of input fields using an intensity-based sensor array without any digital processing. Our design utilizes successive deep learning-optimized diffractive surfaces that are structured to collectively modulate the input complex field, forming two independent imaging channels that perform amplitude-to-amplitude and phase-to-intensity transformations between the input and output planes within a compact optical design, axially spanning ~100 wavelengths. The intensity distributions of the output fields at these two channels on the sensor plane directly correspond to the amplitude and quantitative phase profiles of the input complex field, eliminating the need for any digital image reconstruction algorithms. We experimentally validated the efficacy of our complex field diffractive imager designs through 3D-printed prototypes operating at the terahertz spectrum, with the output amplitude and phase channel images closely aligning with our numerical simulations. We envision that this complex field imager will have various applications in security, biomedical imaging, sensing and material science, among others.

Practical design of an optical filter for thermal management of photovoltaic modules

AbstractThis work presents a practical approach to designing an optical filter for thermal management for photovoltaic modules. The approach emphasizes the practicality of manufacturing over optical performance. Simulation work demonstrates that, for an interdigitated back contact solar cell architecture, complete rejection of infrared radiation offers limited thermal benefits requiring highly complex optical filter designs. An alternative approach consists of reducing thermalization losses by providing reflectance at lower wavelength values. An optical filter design that fulfills this requirement is possible using simple structures based on two materials and taking advantage of the harmonics present in quarter wavelength optical thickness designs. The filter is later optimized for angular performance via second‐order algorithms, resulting in a device consisting of only 15 thin‐film layers. Performance simulations on two locations, Delft (the Netherlands) and Singapore, estimate a temperature reduction of 2.20°C and 2.45°C, respectively. In a single year, the optical loss produced by the filter is not compensated via temperature reduction. However, improvements in the annual degradation rate show that in Singapore, the overall effect of the filter on the lifetime DC energy yield is positive.

Integrated photonic encoder for low power and high-speed image processing.

Modern lens designs are capable of resolving greater than 10 gigapixels, while advances in camera frame-rate and hyperspectral imaging have made data acquisition rates of Terapixel/second a real possibility. The main bottlenecks preventing such high data-rate systems are power consumption and data storage. In this work, we show that analog photonic encoders could address this challenge, enabling high-speed image compression using orders-of-magnitude lower power than digital electronics. Our approach relies on a silicon-photonics front-end to compress raw image data, foregoing energy-intensive image conditioning and reducing data storage requirements. The compression scheme uses a passive disordered photonic structure to perform kernel-type random projections of the raw image data with minimal power consumption and low latency. A back-end neural network can then reconstruct the original images with structural similarity exceeding 90%. This scheme has the potential to process data streams exceeding Terapixel/second using less than 100 fJ/pixel, providing a path to ultra-high-resolution data and image acquisition systems.