Estudio de la extensión de foco en lentes intraoculares de rango extendido

Objectiu: Analitzar les variables que poden influir sobre l'extensió de focus de les lents intraoculars de focus estès. En particular, s'analitzarà la variació de l'extensió de focus amb la potència i la mida de pupil·la de la lent Tecnis EyhanceTM (Johnson & Johnson Vision). Metodologia: Obtenir la funció de transferència de modulació (MTF) en un model d'ull estàndard sobre banc òptic de les lents Eyhance de 10 D, 20 D i 30 D amb diàmetres de pupil·la sobre el plànol de la lent de 3.0 mm i 2.0 mm. Posteriorment, es procedeix a calcular l'àrea sota la corba de la MTF (MTFa) i l'agudesa visual (AV) correlacionada. Resultats: S'obtenen diferències poc significatives en el rendiment de la lent en funció de la potència, essent l'extensió de focus lleugerament més gran amb la lent de 10 D i la qualitat òptica relativament millor amb 30 D. Amb la pupil·la més petita la profunditat de focus augmenta significativament, però es redueix la qualitat òptica. Els resultats obtinguts sobre banc òptic són força concordants amb els resultats clínics obtinguts per alguns grups d'investigació. Conclusions: La potència de la lent Eyhance afecta de manera poc significativa la qualitat òptica i l'extensió de la profunditat de focus. El rendiment de la lent varia notablement amb el diàmetre pupil·lar. S'han d'analitzar més les propietats òptiques i clíniques amb diferents potències de la lent en futurs estudis. Cal assenyalar, com a dificultat, una gran variació entre els estudis clínics a causa de la manca d'estandardització de les proves.Objetivo: Analizar las variables que pueden influir sobre la extensión de foco de las lentes intraoculares de foco extendido. En particular, se analizará la variación de la extensión de foco con la potencia y el tamaño de pupila de la lente Tecnis EyhanceTM (Johnson & Johnson Vision). Metodología: Obtener la función de transferencia de modulación (MTF) en un modelo de ojo estándar sobre banco óptico de las lentes Eyhance de 10 D, 20 D y 30 D con diámetros de pupila sobre el plano de la lente de 3.0 mm y 2.0 mm. Posteriormente, se procede a calcular el área bajo la curva de la MTF (MTFa) y la agudeza visual (AV) correlacionada. Resultados: Se obtienen diferencias poco significativas en el rendimiento de la lente en función de la potencia, siendo la extensión de foco ligeramente mayor con la lente de 10 D y la calidad óptica relativamente mejor con 30 D. Con la pupila más pequeña la profundidad de foco aumenta significativamente, pero se reduce la calidad óptica. Los resultados obtenidos sobre banco óptico son bastante concordantes con los resultados clínicos proporcionados por algunos grupos de investigación. Conclusiones: La potencia de la lente Eyhance afecta de manera poco significativa la calidad óptica y la extensión de la profundidad de foco. El rendimiento de la lente varía notablemente con el diámetro pupilar. Se deben analizar más las propiedades ópticas y clínicas con diferentes potencias de la lente en futuros estudios. Cabe señalar, como dificultad, una gran variación entre los estudios clínicos debido a la falta de estandarización de las pruebas.Purpose: To analyze the variables that can influence the focus extension of extended focus intraocular lenses. Specifically, the variation of the focus extension with the power and pupil size of the Tecnis EyhanceTM (Johnson & Johnson Vision) lens will be analyzed. Methods: Obtain the modulation transfer function (MTF) in a standard eye model on the optical bench of the Eyhance lenses of 10 D, 20 D and 30 D with pupil diameters on the plane of the lens of 3.0 mm and 2.0 mm. Subsequently, we proceed to calculate the area under the curve of the MTF (MTFa) and the correlated visual acuity (AV). Results: Insignificant differences are obtained in lens performance depending on the power, being the slightly larger focus extension with the 10 D lens and the optical quality relatively better with 30 D. With the smaller pupil the depth of focus increases significantly, but the optical quality is reduced. The results obtained on the optical bench are quite consistent with the clinical results provided by some research groups. Conclusions: The power of the Eyhance lens significantly affects optical quality and the extent of focus depth. The performance of the lens varies significantly with the pupil diameter. The optical and clinical properties with different lens powers must be further analyzed in future studies. It should be noted, as difficulty, a great variation between clinical studies due to the lack of standardization of the tests

Textile antenna-sensor for In vitro diagnostics of diabetes

In this paper, a feasibility study of a microwave antenna-based sensor is proposed for in vitro experiments for monitoring blood glucose levels. The proposed device consists of a square-ring incorporated within a fully textile monopole antenna to absorb and sense different glucose concentrations, covering patients with different diabetic conditions. The designed antenna-sensor is optimized to operate at 2.4 GHz. The sensing principle is based on the resonance frequency shift of the reflection response of the antenna-based sensor under different glucose levels. The experiments were carried out with blood mimicking by means of aqueous solutions, using D(+)- glucose/water in different concentrations for various diabetic conditions of type-2 diabetes. The performance of the embroidered antenna-based sensor is characterized and validated using a convenient setup for in vitro measurements. The results demonstrated the ability of the proposed antenna-based sensor to cover all the glucose levels of the diabetes range, including hypoglycemia (10–70 mg/dL), normoglycemia (80–110 mg/dL) and hyperglycemia (130–190 mg/dL) with a sensitivity of 350 kHz/(mg/dL). Besides its ability to detect different glucose concentrations of various diabetic conditions, the proposed antenna-sensor presents diverse features such as a simplistic design, compact size, wearability and low cost. The proposed textile device demonstrates a proof of concept for efficient in vitro blood glucose level measurements and diagnostics of diabetes.This work was supported by the Spanish Government-MINECO under Projects TEC2016- 79465-R.Peer ReviewedPostprint (published version

Breathing pattern characterization based on wireless etextile antenna-sensor for respiratory disease surveillance

Programa de doctorat: Doctorat en Enginyeria Electrònic

Embroidered wearable antenna-based sensor for real-time breath monitoring

© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In this paper we present the design and the validation of a novel fully embroidered meander dipole antenna-based sensor integrated into a commercially available T-shirt for real-time breathing monitoring using the technique based on chest well movement analysis. The embroidered antenna-based sensor is made of a silver-coated nylon thread. The proposed antenna-sensor is integrated into a cotton T-shirt and placed on the middle of the human chest. The breathing antenna-based sensor was designed to operate at 2.4 GHz. The sensing mechanism of the system is based on the resonant frequency shift of the meander dipole antenna-sensor induced by the chest expansion and the displacement of the air volume in the lungs during breathing. The resonant frequency shift was continuously measured using a Vector Network Analyzer (VNA) to a remote PC via LAN interface in real-time. A program was developed via Matlab to collect respiration data information using a PC host via LAN interface to be able to transfer data with instrumentation over TCP/IP. The measurements were carried out to monitor the breathing of a female volunteer for various positions (standing and sitting) with different breathing patterns: eupnea (normal respiration), apnea (absence of breathing), hypopnea (shaloow breathing) and hyperpnea (deep breathing). The measured resonance frequency shift to 2.98 GHz, 3.2 GHz and 2 GHz for standing position and 2.84 GHz, 2.95 GHz and 2.15 GHz for sitting position, for eupnea, hyperpnea and hypopnea, respectively. The area of the textile sensor is 45 x 4.87 mm2 , reducing the surface consumtion significatively with regard to other reported breath wearable sensors for health monitoring.This work was supported by the Spanish Government MINECO under project TEC2016-79465-R.Peer ReviewedPostprint (author's final draft

Wireless communication platform based on an embroidered antenna-sensor for real-time breathing detection

Wearable technology has been getting more attention for monitoring vital signs in various medical fields, particularly in breathing monitoring. To monitor respiratory patterns, there is a current set of challenges related to the lack of user comfort, reliability, and rigidity of the systems, as well as challenges related to processing data. Therefore, the need to develop user-friendly and reliable wireless approaches to address these problems is required. In this paper, a novel, full, compact textile breathing sensor is investigated. Specifically, an embroidered meander dipole antenna sensor integrated into an e-textile T-shirt with a Bluetooth transmitter for real-time breathing monitoring was developed and tested. The proposed antenna-based sensor is designed to transmit data over wireless communication networks at 2.4 GHz and is made of a silver-coated nylon thread. The sensing mechanism of the proposed system is based on the detection of a received signal strength indicator (RSSI) transmitted wirelessly by the antenna-based sensor, which is found to be sensitive to stretch. The respiratory system is placed on the middle of the human chest; the area of the proposed system is 4.5 × 0.48 cm2 , with 2.36 × 3.17 cm2 covered by the transmitter module. The respiratory signal is extracted from the variation of the RSSI signal emitted at 2.4 GHz from the detuned embroidered antenna-based sensor embedded into a commercial T-shirt and detected using a laptop. The experimental results demonstrated that breathing signals can be acquired wirelessly by the RSSI via Bluetooth. The RSSI range change was from -80 dBm to -72 dBm, -88 dBm to -79 dBm and -85 dBm to -80 dBm during inspiration and expiration for normal breathing, speaking and movement, respectively. We tested the feasibility assessment for breathing monitoring and we demonstrated experimentally that the standard wireless networks, which measure the RSSI signal via standard Bluetooth protocol, can be used to detect human respiratory status and patterns in real time.This work was supported by the Spanish Government-MICINN under Projects TED2021- 131209B-I00 and PID2021-124288OB-I00.Peer ReviewedPostprint (published version

Determination of salinity and sugar concentration by means of a circular-ring monopole textile antenna-based sensor

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper presents a monopole antenna-based sensor for measuring different amounts and concentrations of salt and sugar in water. The proposed antenna sensor consists of a textile monopole antenna with circular-ring and partial ground plane. It is implemented by means of embroidery on a felt textile substrate and it resonates at 2.4 GHz. The textile substrate can absorb liquids through the sensing area incorporated within the monopole antenna structure. Therefore, the substrate dielectric properties are changed according to the liquid properties of the absorbed solution. The proposed antenna sensor uses microwave signals to track different amount and concentrations of salt and sugar in terms of the magnitude of the return loss and resonance frequency shift. The measurements are recorded and compared before and after applying different solutions. The rinsing reliability of the proposed antenna sensor has been also studied. The proposed antenna sensor demonstrates a high sensitivity of 800 MHz/mL with a good correlation with the linear fit ( R2=0.9737 ) and 550 MHz/mL with linear response ( R2=0.9135 ) for 5% salt and sugar concentration solutions, respectively. To the best of our knowledge, this article demonstrates for the first time the capability of a fully-textile antenna sensor to detect different amounts and concentrations of salt and sugar using microwave signals.This work was supported by the Spanish Goverment MINECO under Project TEC2016-79465-R.Peer ReviewedPostprint (author's final draft

Analysis on the effects of the human body on the performance of wearable textile antenna in substrate integrated waveguide technology

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A wearable textile circular ring slot antenna based on a substrate integrated waveguide cavity is presented. In this paper, the focus is on studying and understanding the technical behavior of the SIW textile antenna when located near the human body. Thus, based on the electrical properties of conductive material and the dielectric characteristics of the Felt substrate, a 5.5GHz electro-textile antenna was designed. The proposed antennas are simulated in free space, while the performance of antenna is investigated for on-body condition. The simulated impedance bandwidths of the proposed antenna in free space and on phantom are 120MHz and 110MHz at 5.5GHz respectively. The efficiencies of the antenna at 5.5GHz are 95.8% in free space, and 91.6% on phantom, respectively, meanwhile the gains of that are 8.64dB and 9.35dB, respectively.Peer ReviewedPostprint (author's final draft

Design and characterization of wearable antenna sensors for healthcare applications

Tesi en modalitat de compendi de publicacions, amb continguts parcialment retallats per drets de l’editor(English) Wearable antenna sensors are a promising technology for developing new applications in the healthcare field since textiles are widely used by everyone due to the maturity of textile manufacturing. According to the last decade's market behavior, it is expected that consumers will claim smaller and more intelligent communications systems which will improve their quality of life. In this respect, wearable antenna sensor technology is one of the key implementations of the future smart clothes field and they may find their place in our daily life. Currently, the researches on wearable antenna sensors are receiving increasing interest while wearable antenna sensors on textile have less research, thus it is a novelty and motivation of this thesis. This thesis deals with challenges regarding wearable antenna sensor design, characterization, and measurements on textile. Based on the analysis of the current state of the art, there are several new research that merits to be explored, thus generating the specific objectives of this thesis. The first objective is to develop new textile antenna sensors with high performance including low profile, high sensitivity, low cost, and high durability; the second objective is to explore wearable antenna-based sensors that can be used for body signal/healthcare monitoring and communication purposes; the third objective is to test the performance of the antenna sensor in real-world scenarios, such as breathing monitoring, and the fourth objective is to develop antenna sensors that can be integrated into clothing for breathing monitoring combined with other commercial electronic components, such as Bluetooth/WIFI transmitter. For achieving the first objective, an embroidered fully textile antenna-based sensor is proposed to detect various concentrations of salt and sugar using microwave signals. Different concentrations of salt and sugar are identified through variations in frequency shifts and magnitude levels observed in reflection coefficient measurements. In addition, the rinsing reliability validation measurements are performed. The proposed sensor offers high sensitivity and compact size. To achieve the second objective, a textile antenna sensor for in vitro diagnostics of diabetes for monitoring blood glucose levels is proposed. The experiments are performed to detect different diabetic conditions including hypoglycemia, normoglycemia, and hyperglycemia. To attain the third objective, a new embroidered meander dipole antenna-based sensor for real-time breath detection using the technique based on chest well movement analysis is proposed. For the fourth objective, an embroidered antenna-based sensor is integrated into the T-shirt to demonstrate the sensing mechanism based on the detection of different breathing patterns through the resonance shift frequency and the received signal strength indicator (RSSI) using a Bluetooth transmitter. The results show a good sensing performance and its ability to detect and monitor different breathing patterns. This thesis has been developed at RFLEX (Radio Frequency Identification and Flexible Electronics) group, which is part of the Electronic Engineering Department at UPC partially supported by projects: TEC2016-79465-R, TED2021-131209B-I0, and PID2021-124288OB-I0. This Ph.D. thesis has been written as a Compendium of articles, five articles indexed in the Journal Citation Report are already published and one additional is under submission, which are included as an annex in this thesis.(Español) Los sensores de antena portátiles son una tecnología prometedora para el desarrollo de nuevas aplicaciones en el campo de la salud, ya que los textiles son ampliamente utilizados por todos debido a la madurez de los métodos de fabricación textil. De acuerdo con el comportamiento del mercado de la última década, se espera que los consumidores reclamen sistemas de comunicaciones más pequeños e inteligentes que mejoren su calidad de vida. En este sentido, la tecnología de sensor de antena portátil es una de las implementaciones clave del futuro campo de la ropa inteligente y puede encontrar su lugar en nuestra vida diaria. Actualmente, las investigaciones sobre sensores de antena portátiles están recibiendo un interés creciente, mientras que los sensores de antena portátiles en textiles han sido sometidos a menor investigación, por lo que es una novedad y motivación de esta tesis. Esta tesis aborda los desafíos relacionados con el diseño, la caracterización y las mediciones de sensores antena portátiles. En base al análisis del estado del arte actual, hay varias investigaciones nuevas que merecen ser exploradas y que constituyen los objetivos específicos de esta tesis. El primer objetivo es desarrollar nuevos sensores de antena textil con alto rendimiento que incluyan bajo perfil, alta sensibilidad, bajo costo y alta durabilidad; el segundo objetivo es explorar sensores portátiles basados en antenas que se puedan integrarse en la ropa para propósitos de comunicación y monitoreo de señales corporales/salud; el tercer objetivo es probar el rendimiento del sensor de antena en escenarios del mundo real, como el control de la respiración, y el cuarto objetivo es desarrollar sensores de antena que se puedan integrar en la ropa para para monitorear la respiración junto con otros componentes electrónicos comerciales, como el transmisor Bluetooth/WIFI. Para lograr el primer objetivo, se propone un sensor basado en una antena totalmente textil bordado para detectar diferentes concentraciones de sal y azúcar utilizando señales de microondas. Las diferentes concentraciones de sal y azúcar se identifican a través de variaciones en los cambios de frecuencia y los niveles de magnitud observados en las mediciones del coeficiente de reflexión. Además, se realizan las medidas de validación de la fiabilidad del enjuague. El sensor propuesto ofrece alta sensibilidad y tamaño compacto. Para lograr el segundo objetivo, se propone un sensor de antena textil para el diagnóstico in vitro de diabetes para monitorear los niveles de glucosa en sangre. Los experimentos se realizan para detectar diferentes condiciones diabéticas que incluyen hipoglucemia, normoglucemia e hiperglucemia. Para lograr el tercer objetivo, se propone un nuevo sensor basado en una antena dipolo de meandro bordado para la detección de la respiración en tiempo real utilizando la técnica basada en el análisis del movimiento del pecho. Para el cuarto objetivo, se integra un sensor basado en antena bordado en la camiseta para demostrar el mecanismo de detección basado en la detección de diferentes patrones de respiración a través de la frecuencia de cambio de resonancia y el indicador de intensidad de la señal recibida (RSSI) usando un transmisor Bluetooth. Los resultados muestran un buen rendimiento de detección y su capacidad para detectar y monitorear diferentes patrones de respiración. Esta tesis ha sido desarrollada en el grupo RFLEX (Identificación por Radio Frecuencia y Electrónica Flexible), que forma parte del Departamento de Ingeniería Electrónica en la UPC apoyado parcialmente por los proyectos: TEC2016-79465-R, TED2021-131209B-I0, y PID2021-124288OB-I0. Esta tesis doctoral se ha escrito bajo la modalidad de compendio de artículos. Cinco artículos indexados en el Journal Citation Report ya están publicados y uno adicional está en proceso de presentación, los cuales se incluyen como anexo en esta tesis.DOCTORAT EN ENGINYERIA ELECTRÒNICA (Pla 2013

A Review of Flexible Wearable Antenna Sensors: Design, Fabrication Methods, and Applications

This review paper summarizes various approaches developed in the literature for antenna sensors with an emphasis on flexible solutions. The survey helps to recognize the limitations and advantages of this technology. Furthermore, it offers an overview of the main points for the development and design of flexible antenna sensors from the selection of the materials to the framing of the antenna including the different scenario applications. With regard to wearable antenna sensors deployment, a review of the textile materials that have been employed is also presented. Several examples related to human body applications of flexible antenna sensors such as the detection of NaCl and sugar solutions, blood and bodily variables such as temperature, strain, and finger postures are also presented. Future investigation directions and research challenges are proposed

Textile Antenna-Sensor for In Vitro Diagnostics of Diabetes

In this paper, a feasibility study of a microwave antenna-based sensor is proposed for in vitro experiments for monitoring blood glucose levels. The proposed device consists of a square-ring incorporated within a fully textile monopole antenna to absorb and sense different glucose concentrations, covering patients with different diabetic conditions. The designed antenna-sensor is optimized to operate at 2.4 GHz. The sensing principle is based on the resonance frequency shift of the reflection response of the antenna-based sensor under different glucose levels. The experiments were carried out with blood mimicking by means of aqueous solutions, using D(+)- glucose/water in different concentrations for various diabetic conditions of type-2 diabetes. The performance of the embroidered antenna-based sensor is characterized and validated using a convenient setup for in vitro measurements. The results demonstrated the ability of the proposed antenna-based sensor to cover all the glucose levels of the diabetes range, including hypoglycemia (10–70 mg/dL), normoglycemia (80–110 mg/dL) and hyperglycemia (130–190 mg/dL) with a sensitivity of 350 kHz/(mg/dL). Besides its ability to detect different glucose concentrations of various diabetic conditions, the proposed antenna-sensor presents diverse features such as a simplistic design, compact size, wearability and low cost. The proposed textile device demonstrates a proof of concept for efficient in vitro blood glucose level measurements and diagnostics of diabetes