Optical Scanning Research Articles

Photopsias are associated with greater levels of depression and anxiety

ABSTRACT Clinical relevance Vitreous floaters have been associated with depressive and anxiety symptoms. However, there is a scarcity in the literature regarding the possible impact of vitreous flashes on the psychological status of the patients. Background Photopsias and vitreous floaters frequently co-exist. Floaters have been accompanied by exacerbated levels of depression and anxiety. The aim of this study was to examine whether the presence of photopsias in patients suffering from vitreous floaters is accompanied by exacerbated levels of anxiety and depression. Methods One hundred and four patients complaining of floaters were included in the study; 51 experienced also photopsias and 53 did not. A comprehensive ocular examination, including funduscopy and optical coherence tomography scans was performed to every patient, while their clinical and demographic data were also assessed. Every participant completed the PHQ-9, the Zung SDS, and the HADS anxiety and depression questionnaires. Results The clinical and demographic data did not differ significantly between the study groups (p > 0.05).The scores of every questionnaire were significantly higher among the patients with vitreous flashes (p < 0.05 for all). After adjustment for several confounders, the values remained significantly impaired. Conclusion Photopsias negatively affect the psychological and mental well-being of the patients, by the terms of amplified levels of depression and anxiety. These findings underscore the necessity for a more holistic approach to managing patients presenting with vitreous flashes.

Random sparse sampling and compressive sensing based reconstruction for computational optical scanning holography

Random sparse sampling and compressive sensing based reconstruction for computational optical scanning holography

Effect of Pre-Emulsified Flaxseed Oil Containing Rutin on the Quality of Nemipterus virgatus Surimi Gel: Gelatinization Properties, Storage Stability, and Protein Digestibility

Rinsing during surimi protein processing can result in the loss of essential nutrients, such as fats and minerals. Therefore, supplementing functional fats in a stable form can make up for the fat loss of surimi during the rinsing process. This research aimed to investigate the effects of incorporating pre-emulsified flaxseed oil with different concentrations of rutin (0, 0.5, 1.5, 2.5, and 3.5%, dissolved in flaxseed oil, w/v) to Nemipterus virgatus surimi on the gelatinization properties, lipid oxidation, and in vitro static simulated digestion characteristics of surimi gels. The results indicated that the addition of 1.5% rutin significantly improved the water-holding capacity and decreased the cooking loss rate of surimi gel (p &lt; 0.05). The results of optical microscopy and scanning electron microscopy showed that the addition of 1.5% rutin promoted a denser network structure of surimi gel. Furthermore, the incorporation of rutin effectively slowed lipid oxidation in pre-emulsified flaxseed oil surimi gel. Compared with the gel group containing only pre-emulsified flaxseed oil, the addition of rutin significantly reduced the levels of volatile base nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARSs) in the gel and also mitigated the decline in acidity (p &lt; 0.05). Moreover, the addition of rutin significantly inhibited the decrease in pH of surimi gel during storage (p &lt; 0.05). In vitro static simulated digestion demonstrated that the addition of 1.5% rutin enhanced the protein digestibility from 71.2% to 77.2% of the surimi gel. Therefore, adding pre-emulsified oil containing an appropriate amount of rutin to surimi can not only compensate for the fat loss during the surimi rinsing process but also effectively improve the quality characteristics of surimi gels. This research will provide a theoretical basis for the effective addition of functional lipids in surimi products and the development of nutritious and healthy surimi products.

Updates on Methods for Body Composition Analysis: Implications for Clinical Practice.

Recent technological advances have introduced novel methods for measuring body composition, each with unique benefits and limitations. The choice of method often depends on the trade-offs between accuracy, cost, participant burden, and the ability to measure specific body composition compartments. To review the considerations of cost, accuracy, portability, and participant burden in reference and emerging body composition assessment methods, and to evaluate their clinical applicability. A narrative review was conducted comparing traditional reference methods like dual-energy X-ray absorptiometry (DXA), magnetic resonance imaging (MRI), and computed tomography (CT) with emerging technologies such as smartphone camera applications, three-dimensional optical imaging scanners, smartwatch bioelectric impedance analysis (BIA), and ultrasound. Reference methods like CT and MRI offer high accuracy and the ability to distinguish between specific body composition compartments (e.g., visceral, subcutaneous, skeletal muscle mass, and adipose tissue within lean mass) but are expensive and non-portable. Conversely, emerging methods, such as smartwatch BIA and smartphone-based technologies, provide greater accessibility and lower participant burden but with reduced accuracy. Methods like three-dimensional optical imaging scanners balance portability and accuracy, presenting promising potential for population-level applications. The selection of a body composition assessment method should be guided by the clinical context and specific application, considering trade-offs in cost, accuracy, and portability. Emerging methods provide valuable options for population-level assessments, while reference methods remain essential for detailed compartmental analysis.

Computer-aided design and fabrication of statistically shaped nasal prostheses: A feasibility study.

A nasal prosthesis may compensate for a partial or complete defect of the nose associated with trauma or amputation. However, the design and production is time-consuming, expensive, and expertize-dependent. Computer-generated prosthesis models and 3D printing can optimize the process. The purpose of this pilot study was to evaluate a novel method for nasal prosthesis design utilizing statistical shape modeling (SSM) on a cohort of participants. The prosthesis shapes were generated by a design algorithm and fabricated through a 3-dimensionally (3D) printed mold. Combining a semi-automated algorithm with 3D printing reduced the dependence on expertize. A proof-of-concept assessment was conducted by enrolling 20 participants with total nose amputation with a conventionally created prosthesis (Cp). The faces of the participants were scanned with an optical scanner to acquire 3D surface scans that were loaded into the algorithm to create the statistically shape modeled prosthesis (SSMp). Participants were asked to digitally modify the SSMp by changing 9 parameters using the Scalismo Lab software program, allowing them to shape their preferred nose model, the patient-preferred prosthesis (PPp). The SSMps were fabricated using 3D printed molds and mailed to the participants for testing. They were asked to complete questionnaires comprising three FACE-Q modules: satisfaction with the nose and psychological and social function. In addition, the SSMp and Cp were compared with the PPp using anthropometric measurements. Fifteen participants were able to fit the SSMp and complete the questionnaire. The median satisfaction, psychological, and social function scores were 56, 67, and 62, respectively. All 20 participants filled out the questionnaires on their Cp, with scores of 71, 67, and 62, respectively. Anthropometric measurements comparing the SSMp with the PPp showed that the algorithm generates noses with a wider nasal root, a larger nostril floor width to nasal width ratio, a smaller columella length to nasal width as well as nostril floor width ratio than the patients prefer according to their set PPp. Comparing the Cp with the PPp showed a larger nasal width to nasal height ratio and nasal root width to intercanthal distance ratio. SSM can facilitate the design and fabrication of nasal prostheses. Using the current models, however, patients were less satisfied than with prostheses made by the anaplastologist in consultation with the patient. Improving the SSM algorithm and incorporating patient manipulations into the resulting model should increase patient satisfaction and enable the production of nasal prostheses with minimal expert dependence.

Fracture Resistance and Wear Behavior of Ultra‐Thin Occlusal Veneers Made From Translucent Zirconia Ceramics Bonded to Different Tooth Substrates

ABSTRACTObjectiveInvestigation of the mechanical properties of occlusal veneers made from zirconia with varying translucency, bonded to different tooth substrates.Materials and MethodsSixty‐four extracted molars were divided into two groups: preparation within enamel (E) or extending into dentin (D). Veneers were milled from four zirconia ceramics (n = 8): 5Y‐TZP (HT), a multilayer of 5 and 3Y‐TZP (GT), 3Y‐TZP (LT), and 4Y‐TZP (MT). After bonding, specimens underwent thermocycling (7500 cycles; 5°C–55°C) and chewing simulation (1,200,000 cycles; 10 kg), followed by investigation of the wear behavior using optical and laser scanning microscopy. Specimens were then loaded to examine fracture resistance.ResultsAll specimens except one in the HT group survived artificial aging. Zirconia wear was below the resolution of the 3D scanner, with no significant difference in antagonist vertical loss across materials (p &gt; 0.05). Fracture resistance was significantly higher in E‐LT compared with E‐HT (p = 0.003). No significant differences (p &gt; 0.05) were observed in fracture resistance between materials bonded to dentin, or between the materials within different substrates.ConclusionsVeneers made of 3 and 4Y‐TZP zirconia showed promising in vitro performance and fracture resistance, regardless of the tooth substrate. All zirconia ceramics exhibited favorable wear behavior.Clinical SignificanceAs tooth wear rates increase, the use of minimally invasive occlusal veneers is becoming more important. The goal is to create restorations that are both esthetically pleasing and mechanically durable, while keeping them thin to minimize occlusal preparation and still ensure sufficient fracture resistance. Ultra‐thin (0.3 mm in the fissures/0.6 mm at the cusps) occlusal veneers made of 4Y‐TZP, multilayer and 3Y‐TZP zirconia ceramics survived chewing simulation corresponding 5‐years. All zirconia restorations showed wear‐resistant behavior.

Accuracy of digital and conventional implant impressions in edentulous jaws: A clinical comparative study.

This clinical study aimed to evaluate the accuracy of digital and conventional implant impressions in a fully edentulous maxilla and mandible. A 53-year-old edentulous patient with four maxillary and two mandibular implants was selected. Ten intraoral scans (IOS) and a conventional impression per jaw were taken. Clinically verified upper and lower plaster models were digitized using both optical (reference data, n = 10 per model) and tactile laboratory scanner (n = 10 per model). Accuracy was evaluated by comparing the precision and linear/angular deviations of the implants with the reference data. Statistical analyses were conducted using Student's t-test and Kruskal-Wallis test (α = 0.05). In the maxilla, the most significant linear deviations exceeding the 100 µm threshold were found with IOS between implants 1-4. In the mandible, all linear deviations remained below 55 µm. Angular deviations between implants after IOS ranged from 0.01° to 0.40° in the mandible and <0.01° to 1.86° in the maxilla. After tactile scanning, linear deviations did not exceed 100 µm threshold (except in one distance) and angular deviations ranged from 0.04° to 0.54° (mandible) and <0.01° to 2.50° (maxilla). The optical scanner demonstrated significantly higher precision (p < 0.001) compared to the IOS and tactile scanner. Given the significant deviations observed, especially in the maxilla, the optical scanner following conventional impressions remained the preferred method for fully edentulous cases due to its superior accuracy. IOS could be a viable alternative particularly for shorter distances in the edentulous jaw, although the clinical implications of these deviations need to be investigated in future studies.

Equipmentless point-of-care testing of dengue antibodies using ELISA and smartphones.

Infections with the dengue virus affect more than 100 million people every year. The infected can present a mild form of the disease or a severe form, which can, eventually, lead to death. Dengue prevails in tropical and subtropical regions, although increased incidence has been observed in the last years in tempered climates. Vaccines are available but testing for previous infection is often required prior to application. Commercially available ELISA and rapid tests for the diagnosis of dengue IgG do not fulfill individually the performance required by control agencies. In this context, rapid, simple and decentralized point-of-care testing (POCT) is highly desirable. However, POCT approaches available usually offer expensive solutions, often due to the complex complementary hardware required. In this article, an equipmentless system based on a commercial ELISA kit and a smartphone is developed for POCT of dengue antibodies. A customized app provides guiding, optical reading, result reporting and connectivity. The reading method employes an algorithm which requires no external information, other than the available on the digital images from the smartphone camera, to classify samples into positives, negatives or indeterminates. The full system operation, from sample extraction to result reporting, was tested in a low resource medical facility with real patients (n = 26). After comparison with an ELISA reader, a Cohen's κ coefficient of 0.92 was obtained, showing very good agreement between both methods. These results show that it is possible to perform ELISA with no specific equipment, bringing massive testing at low resource facilities one step closer.

Comparison of tooth substance loss and angle deviation in access cavity preparation using guided endodontics and conventional method in calcified canals – An in vitro study

Abstract Aims: This study aimed to evaluate the accuracy of access cavity preparation using guided endodontics (GE) and conventional technique (CT) in calcified canals. Subjects and Methods: Twenty teeth with calcification up to middle third were collected after scanning through RadioVisioGraphy (RVG). Preoperative cone-beam computed tomography (CBCT) scan was done and samples were randomly divided into two groups of ten samples each on the basis of method of access cavity preparation. Group 1: Access cavity was prepared by CT, Group 2: Access cavity was prepared by GE. 3D template and corresponding guide drill were made for group 2 samples after performing optical surface scans. After access cavity preparation, postoperative CBCT scanning was performed for all samples. The amount of tooth structure loss and angle deviation were calculated using Sidexis Software. Statistical Analysis Used: The data were analyzed using IBM SPSS Statistics, version 22. A t-test compared tooth structure loss and angle deviation between groups, and a one-way ANOVA calculated tooth structure loss in multiple directions for both groups (P &lt; 0.001). Results: Our study found that the mean tooth volume loss (17.19 mm3 ± 06.11 standard deviation [SD]) and angle deviation (4.82° ±01.66 SD) in GE was significantly less (P &lt; 0.001) as compared to mean tooth structure loss (38.85 mm3 ± 19.07 SD) and angle deviation (13.16° ±2.34 SD) by CT. Conclusion: GE is more accurate and conservative than CT in management of calcified canals.

Effect of shape and size of implant scan body on scanning accuracy: an in vitro study.

Objectives: Evaluating the effect of shape and size of implant scan body on the accuracy of optical 3D scanning. Materials and methods: Fifteen PEEK scan bodies were milled, including 1 spherical, 9 cylindrical, and 5 cuboidal. The 3D position and angulation of each scan body were measured using a CMM 3 times and a laboratory scanner 10 times. The linear and angular trueness and precision of the scans were calculated by comparing with the CMM measurements. Results: The linear accuracy of the cylindrical scan bodies (9.5±6.2 µm) was significantly higher than those of the cuboidal (17.7±8.1 µm) and spherical scan bodies (12.5±6.5 µm). The cuboidal (0.050±0.009°) showed significantly better angular accuracy than the cylindrical (0.065±0.040°). In the cylindrical group, the narrow (∅4.8 mm) demonstrated significantly inferior accuracy than the wider (∅5.5 mm and ∅6.5 mm)(p=0.003). The tall (12 mm) showed significantly higher angular trueness than the shorter (8 and 4 mm)(p<0.001). In the cuboidal group, the 24 mm2 exhibited significantly poorer angular trueness compared to the 18 mm2 and 30 mm2 (p<0.001) Conclusions: The shape and size of the implant scan body significantly affect the scanning accuracy. Spherical scan bodies cannot transfer implant angulation. Scan bodies with a size of >∅4.8mm and >8 mm seem accurate for transferring the 3D implant position. Clinical significance: The shape and size of scan bodies directly influence the accuracy of 3D scanning. Well-designed scan bodies offer better transfer results, which is crucial for ensuring passive fit of implant prostheses and improving long-term clinical outcomes.

Respiratory System of the Two-Toed Sloth (Choloepus didactylus): Macroscopic, Histological and Scanning Electron Microscopy Analysis.

Relatively little research has been conducted regarding Choloepus didactylus and studies that have been done have mainly covered physiology and morphology, as well as studies on its respiratory system. The objective of this study was to describe the components of the respiratory system of the two-toed sloth and compare it with other species already described in the literature. For this purpose, eight adult animals were used. Macroscopic analyses were carried out on the organs that make up the respiratory system, which confirmed the existence of four cartilages of the larynx, trachea with an average of 37 incomplete tracheal cartilages and lung, highlighting the absence of the accessory pulmonary lobe being composed only of the right cranial and caudal, left cranial and caudal lobes. After the standard protocol, microscopic analyses of fragments of the organs evidenced in the macroscopic study were carried out, using optical microscopy and scanning electron microscopy, in addition to chest x-rays with positive contrast media through orotracheal intubation. Finally, we conclude that microscopically the respiratory system of the two-toed sloth is like other Xenarthra and some domestic animals. Macroscopically, the nose is like Choloepus hoffmanni, the nasal cavity to other species of Xenarthra already described in addition to domestic animals. The trachea differs from other species in terms of the number of tracheal rings and extension. As for the lungs, they were the ones that differed most when compared to other Xenarthra and to domestic animals as it was the species with the least lobation.

MACULAR VOLUME SCAN AS A MARKER OF ANGIOGRAPHIC UVEITIC RETINAL VASCULITIS: A Retrospective Longitudinal Study.

To determine whether optical coherence tomography thickness values from macular volume scans can be used to detect uveitic retinal vasculitis. Retrospective study of patients with noninfectious retinal vasculitis. Fluorescein angiogram and 61-line optical coherence tomography macular volume scans with an overlying Early Treatment Diabetic Retinopathy study grid were obtained. Correlation between 1 mm and 6 mm Early Treatment Diabetic Retinopathy study ring values and posterior pole vasculitis was analyzed. A linear longitudinal model was used to assess the relationship between global retinal vasculitis scores and optical coherence tomography macular thickness parameters. Ninety-nine eyes of 54 patients were included. A total of 460 optical coherence tomography and fluorescein angiogram pairs were analyzed. Central (1 mm) macular thickness was weakly correlated with posterior pole vasculitis (correlation coefficient [rho] = 0.09, P = 0.06). Both the mean 6 mm ring (rho = 0.11, P = 0.018) and the average of the superior and inferior (S/I) 6 mm ring values (rho = 0.13, P = 0.006) were strongly correlated with posterior pole leakage. The longitudinal model showed that S/I 6 mm ring values are associated with vasculitis in the posterior pole, mid, and far periphery ( P < 0.0001). Optical coherence tomography-based macular volume thickness can detect uveitic retinal vasculitis and aid in monitoring disease activity.

MODELAGEM DE MISTURAS BINÁRIAS PELA APLICAÇÃO DA EQUAÇÃO DE SCHRÖEDER-van LAAR A UM CONJUNTO DE SUBSTÂNCIAS COM DIVERSIDADE ESTRUTURAL

MODELING OF BINARY MIXTURES BY APPLYING THE SCHRÖEDER-van LAAR EQUATION TO A SET OF SUBSTANCES WITH STRUCTURAL DIVERSITY. The Schröeder-van Laar equation to predict the theoretical eutectic melting temperature values was applied to a set of fourteen binary mixtures (UR1 to UR14). The fourteen binary mixtures belong to a structurally diverse group of organic molecules. They are represented by the 5-membered heterocycles containing N-S and N-O rings, flexible methylene chains (RH), semi-rigid semi-fluorinated chains (RF), and hydrogen bonds (HB). A virtual screening totalizing ninety-one possible theoretical combinations was planned. The UR1 to UR14 were prepared by mixing individual components using the calculated mole fractions. The experimental (Te) and theoretical (Tt) temperatures for the eutectic melting points were determined using polarized optical microscopy (POM) and differential scanning calorimetry (DSC) techniques. Heterogeneous mixtures were formed for components with large structural diversity as seen by POM. During the melting of the mixtures, irregular behavior through the segregation of the components was recorded. The study showed that the similarities in structural diversities favor the formation of homogeneous mixtures, with Te values approaching Tt, as predicted by the Schröeder-van Laar equation and by the theory of eutectic mixtures. Liquid crystal properties were affected in homogeneous binary mixtures containing one of the individual liquid crystal components.

Association of Blood Pressure and Retinal Nerve Fiber Layer Rates of Thinning in Patients with Moderate to Advanced Glaucoma.

Investigate the influence of baseline blood pressure (BP) on retinal nerve fiber layer (RNFL) rates of change (RoC) in glaucoma patients with central damage or moderate to severe disease. Prospective cohort study. 110 eyes with ≥4 RNFL optical coherence tomography scans and ≥2 years of follow-up. Global RNFL RoC were modeled with a Bayesian hierarchical model with subject- and sector-level random effects. Influence of baseline systolic and diastolic BP measures and their interactions with intraocular pressure (IOP) on global RNFL rates of change was investigated in prognostic models adjusting for relevant baseline demographic and clinical measures. Magnitude and direction of coefficients for BP, IOP, and their interaction for prediction of global RNFL RoC. One-sided Bayesian p-values denote posterior probability that a regression coefficient is greater than or less than zero with p <0.025 or >0.975 defining significance. Average (SD) 24-2 visual field mean deviation (MD) at baseline, follow-up time, and number of OCT scans were -8.8 (6.0) dB, 4.3 (0.5) years, and 8.3 (1.4), respectively. In multivariable analyses, female sex, Hispanic ethnicity (vs. White ethnicity), better baseline 24-2 MD, higher contrast sensitivity at 12 cycles per degree, presence of diabetes, and thicker central corneal predicted faster RNFL thinning. Adjusted for covariates, lower diastolic BP combined with higher IOP predicted faster RNFL rates of change. Parallel multivariable models incorporating systolic BP showed similar effects. Among various BP/IOP combinations, eyes with IOP at the 90th percentile and diastolic (systolic) BP at 10th percentile demonstrated the fastest RNFL thinning rates (-0.554 and -0.539 μm/year). Low BP and higher IOP at baseline predicted faster (worse) RNFL rates of change in glaucoma patients with central damage or moderate to advanced disease. While there may be potential benefits to BP management in glaucoma patients, the therapeutic value of BP manipulation in glaucoma patients is yet to be established given the proven benefits of tight BP control in reducing cardiovascular morbidity and mortality.

The effect of the guide hole height on the accuracy of implant placement: an in-vitro study.

Guided implant surgery using three-dimensional (3-D) planning software and 3-D printed surgical guides has become a critical tool for enhancing accuracy. This study aims to determine the minimum guide hole height necessary to maintain implant placement accuracy. Ten maxillary models with edentulous areas were created using CT and optical scan data. Six sites (for each model) were prepared for implant placement with surgical guides fabricated using a 3-D printer. Sixty implants were placed using these guides and divided into five groups according to the guide hole height (1 to 5 mm). After the placement, digital impressions were taken to assess the accuracy of implant positioning. Deviations between planned and actual implant positions were investigated using computer software, and data were statistically analyzed using ANOVA and Kruskal-Wallis tests. Guide holes with 1 mm height (Group Ⅰ) resulted in the highest 3-D deviations (1.12 ± 0.36 and 1.99 ± 0.74 mm at the coronal and apical positions, respectively), with significant errors at the implant apical position compared to groups with taller guide holes (Groups Ⅳ and Ⅴ) (p=0.005). There were no significant deviations between the 3 mm and 5 mm guide hole heights, with no statistical differences between groups at the x, y, and z-axis in the implant position. A comparison between the group with a guide hole height of 5 mm on one side and the group with a height of 1 mm on both sides revealed a significant difference in implant placement accuracy.

Enhancing Manufacturing Precision: Leveraging Motor Currents Data of Computer Numerical Control Machines for Geometrical Accuracy Prediction Through Machine Learning.

Direct verification of the geometric accuracy of machined parts cannot be performed simultaneously with active machining operations, as it usually requires subsequent inspection with measuring devices such as coordinate measuring machines (CMMs) or optical 3D scanners. This sequential approach increases production time and costs. In this study, we propose a novel indirect measurement method that utilizes motor current data from the controller of a Computer Numerical Control (CNC) machine in combination with machine learning algorithms to predict the geometric accuracy of machined parts in real-time. Different machine learning algorithms, such as Random Forest (RF), k-nearest neighbors (k-NN), and Decision Trees (DT), were used for predictive modeling. Feature extraction was performed using Tsfresh and ROCKET, which allowed us to capture the patterns in the motor current data corresponding to the geometric features of the machined parts. Our predictive models were trained and validated on a dataset that included motor current readings and corresponding geometric measurements of a mounting rail later used in an engine block. The results showed that the proposed approach enabled the prediction of three geometric features of the mounting rail with an accuracy (MAPE) below 0.61% during the learning phase and 0.64% during the testing phase. These results suggest that our method could reduce the need for post-machining inspections and measurements, thereby reducing production time and costs while maintaining required quality standards.

Design and production of personalized cervical orthosis using CAD/CAM systems

The aim of this work was to design and manufacture a personalized cervical orthosis using CAD/CAM systems through additive manufacturing technology. Cervical orthoses are practically used to ensure the stability of the cervical spine. The work was motivated by recent research into personalized orthoses made using additive manufacturing technologies. This study describes the methodology of 3D scanning the cervical area, CAD design, and CAM manufacturing of a personalized cervical orthosis. As a basis for modelling the orthosis, a 3D scan of the subject's head, neck, shoulders, and upper chest was obtained using an optical 3D scanner Artec Eva. The scan was processed in CAD software Meshmixer and served as a basis for the modelling of a personalized cervical orthosis, considering the support points. The orthosis was made by additive manufacturing technology Multi Jet Fusion (MJF) on a HP 5200 3D printer from biocompatible polymer PA12. The advantage of manufacturing a cervical orthosis using MJF technology is the individualized design, improved production efficiency, as well as increased quality and comfort in using the orthosis. It meets attributes such as copying the subject's morphology, airiness, lightness, and easy fastening.

A Practical Usage of Point Spread Function for Industrial Barcode Image Enhancement

Barcodes are extensively utilized across industries for a variety of critical and routine applications, ranging from logistics to inventory management. Their widespread use has driven a high demand for barcode-reading devices. Optical barcode readers rely heavily on camera performance and image quality to achieve successful decoding. However, the cost of these cameras can vary significantly based on factors such as lighting conditions, working distance, and exposure time. To reduce costs without the need to upgrade cameras or other hardware, a computational enhancement approach leveraging the Point Spread Function (PSF) has been developed. This method enhances image quality, ensuring effective barcode decoding even under suboptimal conditions, thereby offering a cost-efficient solution for industrial applications.

Large deflection angle resonant 1D scanning micromirror fabricated with multi jet fusion 3D printed parts

This paper presents a one-dimensional scanning micromirror, utilizing Multi Jet Fusion three-dimensional (3D) printed polyamide 12 as its core material, with a gold-coated silicon mirror in a half-circle extension shape (4.2 mm × 15 mm). The micromirror serves as a horizontal scanner in a two-dimensional scan module for light detection and ranging. It features a self-supported coil for electromagnetic actuation, and its design is validated through analytical and finite element analyses. The magnetic circuit design is assessed with three magnet configurations. Forced air cooling and salt bath annealing processes are performed to mitigate the effect of Joule heating in the coil and improve the mechanical characteristics of the 3D printed structure. A maximum optical scan angle of 34° was achieved at 1,432 Hz with 90.8 mArms under forced air cooling. The salt bath annealing enhances the long-term reliability significantly, with a 12-hour operational test showing a 1.2% variation in resonant frequency.

A comparison of the accuracy and feasibility of a low-cost mobile application versus higher-cost handheld 3D scanner for digital ear prosthetics.

Facial prosthetics are an important means to rehabilitate patients with congenital or acquired facial defects. However, with a time-consuming manual workflow and workforce shortage, access to facial prosthetics is limited in Australia and worldwide, especially for rural and remote patients. Optical 3D scanning has been increasingly integrated in digitizing data. With the development of TrueDepth® camera technology on smartphones, there is increasing availability of mobile applications which can generate 3D images to improve accessibility and reduce cost. This study compares the accuracy of mobile phone applications to high resolution 3D scanners for auricular data acquisition. We conducted a case-control study comparing the EM3D smartphone application (EM3D) with the EinScan Pro 2× Plus Shining 3D handheld scanner (EinScan) in 22 healthy participants equating to 44 ears, using CloudCompare software analysis. On average, EM3D acquired images 2.5 minutes quicker than the EinScan. The mean absolute directional distance difference was 1.10 mm, within the accepted deviation range of 2 mm. Out of the 44 ears, only 1 ear (2.27%) did not meet the accepted value of accuracy within 2 mm. The average completeness was 85% and the overall quality of images obtained from EinScanand EM3D were 53.5% and 57.7%, respectively, through observational analysis. Mobile iPhone applications such as EM3D are a viable alternative to 3D handheld scanners such as EinScan. This study demonstrates reliable results in accuracy, and improved results in time, cost and operational feasibility.