Optical Software Research Articles

Optimized Design with Artificial Intelligence Quantum Dot White Mini LED Backlight Module Development

This study delves into the innovation of mini light-emitting diode (mini-LED) backlight module designs, a significant advancement in display technology. The module comprises a substrate, a receiving plane, and an LED structure, which uses a blue light with specific spectral characteristics. When combined with a red-green quantum dot (QD) film, it produces white light. For improved illumination uniformity, the Mini-LED structure was optimized with a focus on the thickness and concentration of layers, especially the TiO2 diffusion layer. A comprehensive design methodology using LightTools (8.6.0) optical simulation software was employed, linked with MATLAB (R2022a) for varied parameters and using the double deep Q-network (DDQN) algorithm via Python as a reinforcement learning agent. This approach facilitated optimal architecture design based on illumination uniformity. Also, the bidirectional scattering distribution function (BSDF) was employed to calculate the scattering properties of the backlight module’s surface, providing accurate simulation results. The DDQN algorithm enhanced the learning design, reducing simulation runs by 76.7% compared to traditional methods. The optimized solution achieved an impressive illumination uniformity of 83.8%, underscoring the benefits of integrating advanced algorithms into display technology optimization.

Poster (Clinical/Best Practice Implementation) ID 1984972

Background Heart disease is the most common cause of death after spinal cord injury or disease (SCI/D), with Cardiometabolic Disease (CMD) risk a primary contributor. Objectives 1) To report the frequency of Physical Activity guideline adherence; 2) To report the frequency of serum lipid screening recall and their recollection of the result interpretation; among adults living with SCI/D in the community. Methods A Kinesiologist collected the SCI-High outcome data via in person or phone 1:1 interviews, and chart abstraction among UHN outpatients. A Provincial Intake Coordinator collected data via phone interview among outpatients affiliated with SCI Ontario. Survey responses were scored using Reachlite’s optical character recognition software. Descriptive statistics characterize the participant’s age, sex, impairment characteristics, and adherence to physical activity guidelines and the frequency of lipid screening/interpretation recall. Best practice education materials were used to increase future PA guideline adherence, prompt lipid screening, and healthy food choices. Results Adult outpatients (n=127, 67% male), mean age 61 years, and 55% paraplegic consented to participate. In total, 48% (60/126) of outpatients reported engaging in some form of aerobic exercise; of whom 50% (30/60) of these individuals were meeting current PA guidelines. About 51% of outpatients recalled lipid screening within the last year, 33% indicated they had not had an assessment. Clinical interpretation of lipid values was recalled by 71% (53/75) of outpatients. Conclusion Physical activity guideline adherence and routine lipid assessments are integral to CMD risk modification – substantial education resources and recall aids may help to modify CMD risk after SCI/D.

Optical ray-tracing simulation method for the investigation of radiance non-uniformity of an integrating sphere

The paper deals with possibilities and limits of optical simulations of extended uniform light sources. Optical simulations of ideal and real light sources are performed using optical ray-tracing software which is capable to simulate non-imaging systems such as Lambertian disc and integrating spheres. The simulation methodology is validated by comparing the developed simulation model with a real experiment previously performed in optical laboratory. The comparison is made on the radiance uniformity measurement and simulation results of a general purpose integrating sphere rather than on less convenient and more frequent irradiance uniformity measurements. The aim is to develop a reliable simulation method for the investigation of radiance non-uniformity of any real extended uniform light source.

KairoSight-3.0: A validated optical mapping software to characterize cardiac electrophysiology, excitation-contraction coupling, and alternans.

Cardiac optical mapping is an imaging technique that measures fluorescent signals across a cardiac preparation. Dual optical imaging of voltage-sensitive and calcium-sensitive probes allows for simultaneous recordings of cardiac action potentials and intracellular calcium transients with high spatiotemporal resolution. The analysis of these complex optical datasets is both time intensive and technically challenging; as such, we have developed a software package for semi-automated image processing and analysis. Herein, we report an updated version of our software package (KairoSight-3.0) with features to enhance the characterization of cardiac parameters using optical signals. To test software validity and applicability, we used Langendorff-perfused heart preparations to record transmembrane voltage and intracellular calcium signals from the epicardial surface. Isolated hearts from guinea pigs and rats were loaded with a potentiometric dye (RH237) and/or calcium indicator dye (Rhod-2AM) and fluorescent signals were acquired. We used Python 3.8.5 programming language to develop the KairoSight-3.0 software. Cardiac maps were validated with a user-specified manual mapping approach. Manual maps of action potential duration (30 or 80 % repolarization), calcium transient duration (30 or 80 % reuptake), action potential and calcium transient alternans were constituted to validate the accuracy of software-generated maps. Manual and software maps had high accuracy, with >97 % of manual and software values falling within 10 ms of each other and >75 % within 5 ms for action potential duration and calcium transient duration measurements (n = 1000-2000 pixels). Further, our software package includes additional measurement tools to analyze signal-to-noise ratio, conduction velocity, action potential and calcium transient alternans, and action potential-calcium transient coupling time to produce physiologically meaningful optical maps. KairoSight-3.0 has enhanced capabilities to perform measurements of cardiac electrophysiology, calcium handling, alternans, and the excitation-contraction coupling with satisfactory accuracy.

Poster (Clinical/Best Practice Implementation) ID 1984967

Background Assessment of physical activity (PA) prescription recall and serum screening for dyslipidemia are critical to describe and mitigate Cardiometabolic Disease (CMD) risk among adults with spinal cord injury or disease (SCI/D). Objectives To report: 1) the frequency of PA prescription recall; and, 2) the frequency of lipid profile assessment and interpretation recall among inpatients with SCI/D during rehabilitation. Methods Adults with SCI/D completed the SCI-HIGH CMD intermediary outcome indicators. A Kinesiologist collected data via interview and chart abstraction among UHN inpatients. Survey responses were scored using Reachlite’s optical character recognition software. Descriptive statistics were used to characterize the participant’s age, sex, impairment characteristics, and report recall rates and the frequency of lipid screening/interpretation. Based on the participant’s needs, either educational materials to increase future adherence to PA guidelines and/or a Mediterranean diet were provided. Results Adult inpatients (n=124), mean age 59 years, 64% paraplegic, and 36% female participated. In total, 14% of participants (16/117) reported being taught the benefits of PA for their heart health; of whom 69% (11/16) recalled exercise instruction. Similarly, 15% of inpatients (17/114) recalled lipid screening during rehabilitation, although chart abstraction revealed that 30% (37/124) had completed lipid screening. Clinical interpretation of their lipid values was recalled by 30% of inpatients. Conclusion There is a significant opportunity to advance PA instruction and lipid profile education and management among inpatients with SCI/D to reduce CMD risk. Inclusion of PA and lipid management instructions in patient-oriented discharge summaries may enhance patient recall/adherence.

Pupil aberrations correction of the afocal telescope for the TianQin project

TianQin is a planned Chinese space-based gravitational wave (GW) observatory with a frequency band of 10−4–1 Hz. Optical telescopes are essential for the delivery of the measurement beam to support a precise distance measurement between pairs of proof masses. As the design is driven by the interferometric displacement sensitivity requirements, the stability control of optical path length (OPL) is extremely important beyond the traditional requirement of diffraction-limited imaging quality. The recurring tilt-to-length (TTL) coupling noise arises from the OPL variation due to the wavefront deformation and angular misalignment. Reducing the residual chief ray aberration in the optical design helps suppress TTL coupling noise. To correct the pupil aberrations, we derive primary pupil aberrations in a series expansion form, and then refine the formulation of merit function by combining the pupil aberration theory and traditional image aberration theory. The automatic correction of pupil aberrations is carried out by using the macro programming in the commercial optical software Zemax, leading to a high performance telescope design. The design results show that on one side the pupil aberrations have been corrected, and on the other side, its optical performance meets the requirements for TianQin project. The RMS wavefront error over the science field of view (FOV) is less than λ/200 and the maximum TTL coupling noise over the entire ±300 μrad FOV is 0.0152 nm µrad−1 . We believe that our design approach can be a good guide for the space telescope design in any other space-based GW detection project, as well as other similar optical systems.

ATTENUATION ANALYSIS ON FIBER TO THE HOME (FTTH) NETWORK WITH GIGABIT PASSIVE OPTICAL NETWROK (GPON) AT OXYGEN HOME PONTIANAK

Optical fiber as a transmission medium that meets the needs of the internet with large bandwidth. The FTTH (Fiber To The Home) network can deliver a variety of digital information, such as voice, video and data more effectively so that it can support the Triple Play service marketed by Oxygen Home. To determine the feasibility and performance of the FTTH (Fiber To The Home) design system in the Bali Agung 2 Complex, South Pontianak, it will be assessed based on test parameters. The test parameters are Power Link Budget for system feasibility and BER (Bit Error Ratio) will be displayed with an eye diagram for system performance used using Optisystem software, Optisystem is software that can be used to simulate a fiber optic network from central to end – user. From the results of the FTTH network simulator using optical system software, it is found that the farthest user attenuation value is Prx: -16.018 dBm, 1.4804 x 10-61 and Q factor 16.5122. The results obtained are feasible because they are above the minimum FTTH network standard with GPON technology

Study on infrared emissivity model based on perturbation method and Kirchhoff approximation and its application in aluminum alloy welding

Infrared temperature measurement ubiquitously finds applications across multifarious domains. The surface infrared emissivity constitutes the critical parameter influencing the precision of infrared temperature measurement. Therefore, investigating the surface infrared emissivity is of tremendous significance. This paper establishes an infrared emissivity analytical model for rough texture surfaces by considering the repercussions of roughness on the infrared emissivity of material surfaces. First, power spectrum analysis of random roughness is performed. The positive and negative power law components of the rough surface model are constructed using the Monte Carlo method and fractal theory, respectively. Second, based on the perturbation method and Kirchhoff approximation, the infrared emissivity model for rough textured surfaces is established. Third, the infrared emissivity of rough textured surfaces with different fractal dimensions (D), characteristic length scales (G), and surface textures is simulated using the FDTD optical simulation software to validate the efficacy of the infrared emissivity model. Finally, the infrared emissivity model is applied to the temperature measurement system of aluminum alloy friction stir welding. The infrared measurement precision before and after rectification is contrasted and scrutinized to validate the accuracy of this model.

Ring Resonator of Hollow-Core Photonic Crystal Fiber Based on Spatial Coupling Scheme

In this paper, we proposed a hollow-core photonic crystal fiber (HCPCF) ring resonator based on a spatial coupling method, and the component is only 22×30×6mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . When using a 7-core photonic crystal fiber with a mode field diameter of 10um, a ring resonator with the measured finesse of 18 can be built, indicating that the coupling loss is as low as 0.41dB. Compact and low-loss closed resonator is accomplished using a highly integrated free space silicon optical bench manufactured by deep silicon etching and tiny optical lens package technology, which promotes the practicality of the HCPCF gyro. In addition, two important factors affecting the spatial optical coupling efficiency, the lens type and the fiber mode field size, are investigated in this paper. The obtained results are instructive for all spatial optical coupling systems.

Reproducibility of an Artificial Intelligence Optical Coherence Tomography Software for Tissue Characterization: Implications for the Design of Longitudinal Studies

Reproducibility of an Artificial Intelligence Optical Coherence Tomography Software for Tissue Characterization: Implications for the Design of Longitudinal Studies

Analysis and Experiment of Laser Energy Distribution of Laser Wireless Power Transmission Based on a Powersphere Receiver

Laser wireless power transmission (WPT) is one of the most important technologies in the field of long-range power transfer. This technique uses a laser as a transmission medium instead of conventional physical or electrical connections to perform WPT. It has the characteristics of long transmission distance and flexible operation. The existing laser wireless power transmission system uses photovoltaic cells as a receiver, which convert light into electricity. Due to the contradiction between the Gaussian distribution of laser and the uniform illumination requirements of photovoltaic cells, the laser wireless power transmission technology has problems such as low transmission efficiency and small output power. Therefore, understanding the energy distribution changes in the laser during transmission, especially the energy change after the laser is transmitted to each key device, and analyzing the influencing factors of the energy distribution state, are of great significance in improving the transmission efficiency and reducing the energy loss in the system. This article utilizes the optical software Lighttools as a tool to establish a laser wireless power transmission model based on a powersphere. This model is used to study the energy distribution changes in the laser as it passes through various components, and to analyze the corresponding influencing factors. To further validate the simulation results, an experimental platform was constructed using a semiconductor laser, beam expander, Fresnel lens, and powersphere as components. A beam quality analyzer was used to measure and analyze the laser energy distribution of each component except for the powersphere. The output voltage and current values of various regions of the powersphere were measured using a multimeter. The energy distribution of the powersphere was reflected based on the linear relationship between photo-generated current, voltage, and light intensity. The experimental results obtained were in good agreement with the simulation results. Simulations and experiments have shown that using a beam expander can reduce divergence angle and energy loss, while employing large-aperture focusing lens can enhance energy collection and output power, providing a basis for improving the efficiency of laser wireless power transfer.

Reproducibility of an artificial intelligence optical coherence tomography software for tissue characterization: Implications for the design of longitudinal studies

BackgroundTo assess the reproducibility of coronary tissue characterization by an Artificial Intelligence Optical Coherence Tomography software (OctPlus, Shanghai Pulse Medical Imaging Technology Inc.). Methods74 patients presenting with multivessel ST-segment elevation myocardial infarction (STEMI) underwent optical coherence tomography (OCT) of the infarct-related artery at the end of primary percutaneous coronary intervention (PPCI) and during staged PCI (SPCI) within 7 days thereafter in the MATRIX (Minimizing Adverse Hemorrhagic Events by Transradial Access Site and angioX) Treatment-Duration study (ClinicalTrials.gov, NCT01433627). OCT films were run through the OctPlus software. The same region of interest between either side of the stent and the first branch was identified on OCT films for each patient at PPCI and SPCI, thus generating 94 pairs of segments. 42 pairs of segments were re-analyzed for intra-software difference. Five plaque characteristics including cholesterol crystal, fibrous tissue, calcium, lipid, and macrophage content were analyzed for various parameters (span angle, thickness, and area). ResultsThere was no statistically significant inter-catheter (between PPCI and SPCI) or intra-software difference in the mean values of all the parameters. Inter-catheter correlation for area was best seen for calcification [intraclass correlation coefficient (ICC) 0.86], followed by fibrous tissue (ICC 0.87), lipid (ICC 0.62), and macrophage (ICC 0.43). Some of the inter-catheter relative differences for area measurements were large: calcification 9.75 %; cholesterol crystal 74.10 %; fibrous tissue 5.90 %; lipid 4.66 %; and macrophage 1.23 %. By the intra-software measurements, there was an excellent correlation (ICC > 0.9) for all tissue types. The relative differences for area measurements were: calcification 0.64 %; cholesterol crystal 5.34 %; fibrous tissue 0.19 %; lipid 1.07 %; and macrophage 0.60 %. Features of vulnerable plaque, minimum fibrous cap thickness and lipid area showed acceptable reproducibility. ConclusionThe present study demonstrates an overall good reproducibility of tissue characterization by the Artificial Intelligence Optical Coherence Tomography software. In future longitudinal studies, investigators may use discretion in selecting the imaging endpoints and sample size, accounting for the observed relative differences in this study.

The Influence of Wire Diameter Uniformity on the Quality of Fiber Optic Wire Package

The fiber optic wire package is the core component of fiber optic guided rockets. Due to the non-uniformity of the fiber optic wire diameter, the winding process is prone to winding defects, which affects the missile launch process. In this paper, a finite element simulation model for the winding process of the fiber optic wire package is established. The accuracy of the simulation model is verified by comparing it with the analytical model for the contact pressure between fiber optic layers. Then finite element models considering the wire diameter tolerance are established to analyze the effect of diameter uniformity on the winding quality of the fiber package. The results show that the stress distribution of a fiber optic package becomes increasingly uneven with increasing wire diameter non-uniformity, and the structural stability of the package decreases. The edge fibers of a 20-layer optical fiber package are easily extruded when the deviation from the nominal diameter is more than 3%. This study helps to guide the manufacturing accuracy of optical fibers and improve the structural stability of the wire package.

Four-dimensional dynamics of multirotational transition stimulated rotational Raman scattering in air

Stimulated rotational Raman scattering in air is a powerful parasitic process that degrades high intensity laser beams and pulses propagated over significant distances. Conversely, it is used beneficially in the context of Raman lasers. Through this inelastic scattering process, laser photons are converted to higher (anti-Stokes) or lower (Stokes) energies, according to rotational mode transitions in nitrogen and oxygen diatomic molecules. The full wave-mixing problem involves numerous frequencies, and it is consistently assumed that only one rotational mode contributes to the conversion process. We instead present a dynamic 4D multirotational model that is implemented in a parallelized manner within the Virtual Beamline++ optical modeling package allowing high-resolution 4D studies. We highlight the effect that spontaneous emission plays in large and small beam-width setups, even in the highly saturating regime. The weaker transition modes play a large role in the persistent dynamics and can lead to complex spatiotemporal coupling through nonlinear competition of the modes. We highlight how and why these weaker modes persist, how the size and shape of speckle patterns depends highly on the initial beam profile, and how weaker modes can transiently become stronger as a result of such competition.

Fiber array to chip attach using laser fusion splicing for low loss.

With the ever-increasing need for higher data rates, datacom and telecom industries are now migrating to silicon photonics to achieve higher data rates with reduced manufacturing costs. However, the optical packaging of integrated photonic devices with multiple I/O ports remains a slow and expensive process. We introduce an optical packaging technique to attach fiber arrays to a photonic chip in a single shot using CO2 laser fusion splicing. We show a minimum coupling loss of 1.1 dB, 1.5 dB, and 1.4 dB per-facet for 2, 4, and 8-fiber arrays (respectively) fused to the oxide mode converters using a single shot from the CO2 laser.

Design of illumination system using characterized illuminances for smartphone-based fundus camera

Recently, smartphone-based fundus camera (SBFC) research has been actively conducted in response to the need to expand medical infrastructure in underdeveloped countries and the increased telemedicine since the COVID-19 pandemic. Compared to the conventional table-top system, SBFCs have technical challenges that make it difficult to guarantee uniform illumination and avoid back-reflection because of the design constraints of minimizing the form factor and cost. This paper proposes a novel illumination design methodology using characterized illuminance to obtain high-quality fundus images for SBFCs. Key performance indicators (KPIs), such as retinal uniformity, back-reflection suppression, and optical efficiency, were defined to evaluate the performance of the illumination system. Each KPI was calculated using optical simulation software based on Monte-Carlo ray tracing and mapped into a normalized three-dimensional coordinate, the retinal illumination performance space (RIPS). In RIPS, the KPIs are combined into a single parameter ΔRIPS, which is the quantitative difference evaluated as the Euclidean distance between the ideal and actual design point. A compact SBFC illumination system with five design variables was presented to verify the proposed methodology. The final design values at the minimum ΔRIPS were determined using the Taguchi method and response surface methodology. Finally, a working prototype was built, and fundus images were acquired by clinical testing under institutional review board approval. The fundus image had sufficient brightness and resolution to diagnose the lesion with a viewing angle of approximately 50° in one shot.

Determination of the ion beam energy width in tandem Van de Graaff accelerators via Auger projectile spectroscopy

Fast ion beams delivered by tandem Van de Graaff accelerators intrinsically have an energy width, ΔEP/EP, due to the voltage ripple of the accelerator, the production mechanism of the highly charged ions inside the tank of the accelerator, as well as geometrical considerations related to the propagation of the ion beam. The ion beam energy width directly affects the experimental resolution and thus its value should be considered in experiments and the corresponding data analysis. Here, we present a method for determining the energy width of ion beams delivered by tandem Van de Graaff accelerators, based on high resolution Auger projectile electron spectroscopy combined with data analysis via Monte Carlo simulations within the SIMION ion optics package.

Simulation analysis of underwater wireless optical communication based on Monte Carlo method and experimental research in complex hydrological environment

This paper aims to address the challenges of short optical communication distances and high Bit Error Rates (BERs) caused by seawater absorption, scattering, and underwater turbulence. This paper establishes an optical communication channel model based on the Monte Carlo method and simulates and analyzes the process of received optical power attenuation when light is transmitted underwater due to absorption and scattering. The simulation model focuses on the influence of seawater type, transmission distance, receiver position, and angle on the received optical power attenuation. The results of this simulation will provide theoretical support for the development of prototype underwater optical communication systems and experiments in complex environments. To solve the long-range weak signal reception and processing issues in underwater optical wireless communication systems, this paper proposes the design and implementation of an underwater optical wireless communication system using optimized on-off keying high-power light-emitting diode/laser diode modulation technology and avalanche photodiode (APD)/photomultiplier (PMT) receiver modules. In addition, this paper describes the design of the underwater optical communication host computer software, which provides functions such as mode selection, BER monitoring, and file transfer. To test the performance of the proposed system, this paper conducts experiments in a 35 m long pool, fixed platform, and underwater mobile platform, as well as cross-air-water interface optical communication performance test experiments in a complex hydrological environment. The results show that the system achieved a 35 m underwater medium communication distance, transmission rate of 5–20 Mbps, and cross-domain wireless optical communication function under the condition of a BER of less than 10−6. The experiments also revealed that the communication distance decreases as the turbidity of the water body increases and the PMT receiver module selected at the receiver end has a longer communication distance than the APD receiver module. Overall, this paper demonstrates the feasibility of the proposed technology for underwater optical communication systems in complex waters, providing theoretical and data support for the next engineering practice.

Effect of Phase Change Materials on the Optical Path of LEDs for Opto-Thermal Enhancement

A novel concept based on the encapsulation of transparent phase change materials (PCMs) into the optical packaging structure of light-emitting diodes (LEDs) is presented in this article. The concept was initiated by challenges of thermal management of photoluminescent particles in high-power optical systems. LEDs, white LEDs (WLEDs), and porous/network-based photoluminescent matrices can achieve improved thermal networks by embedding PCMs. In this article, paraffin is selected as a suitable PCM encapsulant, and aside from thermal perspectives, an unexpected optical benefit with melted paraffin after surface wetting of the chip was observed. Immersing an LED chip in a melted paraffin pool showed up to an 8% increase in light extraction efficiency and a 1.5% increase in power conversion efficiency (PCE). An accurate dynamic opto-electro-thermal monitoring of studied devices was used to support the proof of concept. This viable method can be integrated into current industrial packaging processes.

Structure optimization, optical design and thermal management of UVC LED photoreactor to improve its inactivation efficiency

Compared with the chlorine disinfection, ultraviolet light emitting diode (UV LED) has attracted extensive interest due to its advantages of environmental friendliness, wide inactivation range and easy automation. However, there are still some challenges on how to apply UV LED to water disinfection more effectively by designing and optimizing some parameters. In this manuscript, the optimal numbers, spacing and configuration of UVC LEDs are systematically studied using the thermal and optical software simulation and experiment methods. Then, the influence of the reactor shape and reflective material on inactivation efficiency of the photoreactor was studied in detail. The results show that the appropriate numbers and spacing of UVC LEDs is helpful not only to increase the average irradiance and petri factor of reactor surface but also to keep a low chip junction temperature. The simulation results of three UVC LED configurations indicate the four corners configuration exhibits the highest average irradiance and petri factor value. The introduction of reflective materials can enhance the inactivation performance, and especially the polytetrafluoroethylene (PTFE) material can effectively increase the inactivation efficiency of module by ∼42% because of higher reflectivity and light uniformity. The further inactivation experiments reveal that the designed cylinder reactor covered with PTFE materials has the maximum log inactivation value. The current research results can provide some reliable suggestions for the design and optimization of UVC LED photoreactor to improve its inactivation effect through optical simulation and experimental methods.