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Za analizo svetlobnih signalov so detektorji svetlobe najbolje implementirani na način, ki omogoča linearnost odziva, visoko pasovno širino, nizek šum in nizek vpliv neželenih tokov in napetosti, ki lahko vplivajo na signal. V primeru visokih frekvenc in višjih ojačenj pulzno krmiljenih virov, je zaradi vpliva parazitne kapacitivnosti ali omejitev komponent, signal na izhodu lahko neustrezen. V diplomski nalogi začnemo z implementacijo detektorja na transimpedančni način, ki izboljša vse omenjene lastnosti. Načrtamo in dizajniramo vezje, primerjamo odziv fotodiode in fototranzistorja, ter se lotimo izboljšav vezja s fotodiodo, ki pri zastavljenih pogojih daje ustreznejši odziv. Vezje razdelimo na tri stopnje. Pri izboljšavah se osredotočimo predvsem na pohitritev signala pri visokih ojačenjih, znižanje vpliva parazitne kapacitivnosti zaradi dodanih uporov, med katerimi izbiramo glede na željeno ojačenje, realizacijo vezja s čim manjšim številom komponent ter nizko ceno celotnega izdelka. Nazadnje optimiziramo še drugo in tretjo stopnjo. In light analysis circuits, light detectors are best implemented in a way, that enables linearity of the response, wide bandwidth, low noise and low effect of unwanted currents and voltages, that can affect the signal. In case of higher frequencies and higher gain of pulse driven light sources, the output signal can become inadequate, due to effect of parasitic capacitance or the component’s limitations. In this thesis, we start by implementing the detector in a transimpedance circuit, which improves all the mentioned characteristics. We construct and design a printed circuit, compare the response of a photodiode and a phototransistor, and start improving the photodiode circuit, which gives a better response, based on the requirements. The circuit is divided into three stages. The improvements mostly focus on optimising the speed at higher gain, lowering the effect of parasitic capacitance, caused by the added resistances, from which we are choosing based on the required gain and the realisation of the circuit with the least number of components as well as a low price of the final product. Finally, we also optimize the two remaining stages.

An Alpha-particle detection system for dark environment is developed. This system is capable to detect alpha-induced UV lights from few meters’ distance. A photomultiplier tube is used to detect the UV lights from ionized nitrogen.

Wearable devices provide their users with feedback and guidance for daily behavior. The objective of this thesis was to develop new algorithms for wearable devices and validate them for long-term assessment of human health-related behavior. In addition to technical accuracy, attention was also paid to feasible long-term use and usability as a research tool at big scale. The main sensor arrangements in this work were a digital accelerometer integrated into a wrist-band and optical photoplethysmographic sensor integrated into a wellness ring. In this work, new algorithms were developed for quantification of daily physical activity and sleep schedule. The same technology was also used to evaluate physiological responses in resting heart rate and heart rate variability. The measurements were validated against gold standard methods. In addition to separate measurements, the use of the sensor solutions was extended to a combined big data evaluation of lifestyle factors, sleep quality and body responses. The algorithms embedded in the wrist-band were able to detect a training-induced change in daily energy expenditure. The developed models explained 62–85% of the inter-individual variability in total energy expenditure. High agreement between ring PPG and the ECG based measurement of night-time heart rate variability was shown (r2=0.980). In addition, the results showed that the data gathered with the ring reflect behavioral, societal and seasonal effects on resting heart rate at the population scale. Moreover, the collected data displayed how bedtime inconsistency and alcohol consumption negatively affect human recovery by means of reduced HRV and worsened sleep quality. The solutions developed in this work combine daily physical activity and nightly recovery metrics. The methodology has already been embedded in commercial devices that are used world-wide. The biggest dataset of this work analyzes human body responses from over 55,000 subjects and provides the highest available precision for human responses to seasons. This work studied healthy individuals; future work will enable more accurate tracking of other groups as well, including people with physical disability, pregnancy and arrhythmia. Tiivistelmä Puettavan teknologian tuotteet tarjoavat käyttäjilleen henkilökohtaisen palautejärjestelmän päivittäisen käyttäytymisen seurantaan ja ohjaukseen. Tämän tutkimuksen tavoitteena oli kehittää ja validoida uutta puettavaa anturiteknologiaa terveyskäyttäytymisen mittaamiseen. Teknisen suorituskyvyn lisäksi kehitettävältä teknologialta edellytettiin käyttömukavuutta pitkäaikaisissa mittauksissa ja käyttökelpoisuutta tutkimustyökaluna laajoissa aineistoissa. Väitöskirjatyön tärkeimmät mittausjärjestelyt olivat rannekkeeseen integroitu digitaalinen kiihtyvyysanturi ja hyvinvointisormukseen integroitu pulssimittaus. Työssä kehitettiin laskentamenetelmät päivittäisen liikunta-aktiivisuuden ja unirytmin mittausta varten. Samalla teknologialla mitattiin myös kehon fysiologisia vasteita — leposykettä ja sykevaihtelua. Mittaukset validoitiin luotettavilla vertailumenetelmillä. Erillisten mittausten lisäksi työssä yhdistettiin päivän toiminnan, yöunen laadun ja kehon vasteiden havainnointi laajoissa aineistoissa. Rannemittariin integroidulla laskentamenetelmällä pystyttiin toteamaan liikuntaharjoittelun vaikutus päivittäiseen energiankulutukseen. Kehitetyt mallit selittivät 62–85 % yksilöiden välisestä päivittäisen energiankulutuksen vaihtelusta. Sormuksessa toimiva sykevaihtelun arviointimenetelmä voitiin todeta erittäin luotettavaksi EKG:hen verrattuna yön yli tehtävissä mittauksissa (r2 = 0,980). Tulosten mukaan sormuksella kerätyllä datalla pystyttiin myös havainnollistamaan käyttäytymisen ja vuodenaikoihin liittyvien tekijöiden vaikutuksia leposykkeeseen ja sykevaihteluun. Analysoitu data esimerkiksi osoitti unirytmin epäsäännöllisyyden ja alkoholinkäytön vaikuttavan kielteisesti palautumiseen, mikä ilmeni alentuneena sykevaihteluna ja huonompana unen laatuna. Työssä kehitetyt ratkaisut yhdistävät päivän aktiivisuuden ja yön palauttavuuden mittauksen. Menetelmät on otettu käyttöön kuluttajatuotteissa, joita käytetään eri puolilla maailmaa. Suurin aineisto tarkastelee yli 55 000 käyttäjän leposykkeitä ja muodostaa laajimman koskaan toteutetun vuodenaikaan liittyvien fysiologisten vasteiden tutkimuksen. Tämän tutkimuksen aineistot koostuivat pääsääntöisesti terveistä henkilöistä; tulevat tutkimukset selvittävät kehitetyn teknologian soveltuvuutta myös muille käyttäjäryhmille, esimerkiksi liikuntarajoitteisille, raskaana oleville ja rytmihäiriöistä kärsiville.

By the current processing technology, it is a challenge to obtain ultrahigh-density information storage in the conventional binary floating-gate-based organic field-effect transistor (FG-OFET) nonvolatile memories (NVMs). To develop a multilevel memory in one cell is a feasible solution. In this work, we demonstrate FG-OFET NVMs with an integrated polymer floating-gate/tunneling (I-FG/T) layer consisting of poly(9,9-dioctylfluorene

International audience; The CALDER project aims to realize cryogenic light detectors for the next generation of experiments searching for rare events. More in detail, the main application of these devices will be the background suppression in future cryogenic calorimetric experiments searching for neutrinoless double beta decay ($0\nu $DBD). This is the case of CUPID, a next-generation $0\nu $DBD observatory, able to take advantage from particle identification to dramatically reduce the background events. In this contribution, we show the status of the CALDER project. The light sensors developed in this R&D are based on kinetic inductance detector operated in the phonon-mediated approach. Their energy resolution (20 eV), time response ($\upmu $s) and multiplexing capability make them very promising for the future CUPID experiment.

COSINUS (Cryogenic Observatory for SIgnatures seen in Next-generation Underground Searches) is an experiment employing cryogenic calorimeters, dedicated to direct dark matter search in underground laboratories. Its goal is to cross-check the annual modulation signal the DAMA collaboration has been detecting for about 20 years (Bernabei et al. in Nucl Part Phys Proc 303–305:74–79, 2018. 10.1016/j.nuclphysbps.2019.03.015) and which has been ruled out by other experiments in certain dark matter scenarios. COSINUS can provide a model-independent test by the use of the same target material (NaI), with the additional chance of discriminating $$\beta /\gamma$$ β / γ events from nuclear recoils on an event-by-event basis, by the application of a well-established temperature sensor technology developed within the CRESST collaboration. Each module is constituted by two detectors: the light detector, that is a silicon beaker equipped with a transition edge sensor (TES), and the phonon detector, a small cubic NaI crystal interfaced with a carrier of a harder material (e.g. $$\hbox {CdWO}_4$$ CdWO 4 ), also instrumented with a TES. This technology had so far never been applied to NaI crystals because of several well-known obstacles, and COSINUS is the first experiment which succeeded in operating NaI crystals as cryogenic calorimeters. Here, we present the COSINUS project, describe the achievements and the challenges of the COSINUS prototype development and discuss the status and the perspectives of this NaI-based cryogenic frontier.

Тема выпускной квалификационной работы: ”Исследование и разработка модуля управления автоматической системы освещения”. Целью данной работы является разработка модуля управления автоматической системы управления освещением одного или Ð½ÐµÑÐºÐ¾Ð»ÑŒÐºÐ¸Ñ Ñ€ÑÐ´Ð¾Ð¼ Ñ€Ð°ÑÐ¿Ð¾Ð»Ð¾Ð¶ÐµÐ½Ð½Ñ‹Ñ Ð¾ÑÐ²ÐµÑ‚Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ Ð¿Ñ€Ð¸Ð±Ð¾Ñ€Ð¾Ð². Задачи, которые решались в Ñ Ð¾Ð´Ðµ выполнения работы: - Разработка и отладка программы, обеспечивающей работу модуля управления - Разработка модели системы модуль управления - осветительный прибор - датчик освещенности в системе Proteus - Исследование на модели Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸Ðº пары светодиод - датчик освещенности - Исследование замкнутой системы регулирования освещенности на основе модели Помимо разработки и отладки модели модуля управления, было проведено исследование модели осветительный прибор - датчик освещенности. Кроме того, сняты и проанализированы Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸ÐºÐ¸ системы без обратной связи и с обратной связью, а также ÑÑ‚Ð°Ñ‚Ð¸Ñ‡ÐµÑÐºÐ¸Ñ Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸Ðº П и ПИД регуляторов. В результате выполнения работы была построена модель в среде Proteus и разработана программа управления для микроконтроллера., The subject of the graduate qualification paper is "Study and development of control module for the automated system of light-control". The purpose of this work is to develop the control module for the automated system of light-control of one or a group of closely spaced light fixtures. Tasks, that were solved during the work: - Development and debugging of program, that runs the control module - Development of model of system control module - light fixture - light sensor in Proteus system - On-model study of specification of the LED - light sensor bunch - Study of closed regulation system of light, based on model Besides development and debugging the model of control module, a study of model light fixture - light sensor was conducted. Aside from that, charachteristics of system with and without the feedback were taken and analyzed, as well as static characteristics of P and PID controllers. As a result, the Proteus system model was created, as well as the program to run the microcontroller.

This study aims to develop a system of crop spraying in the greenhouse using a microcontroller ATMega8535 automated. The benefits of automa-tion is the reduction in consumption of spraying time on the process of spraying, reduced manpower requirements, and increase the volume of spray so that the plants are watered harvest results as expected. The research was done by design, give depth and implement components system that includes: (1) mikorokontroler as process controllers, (2) DC motor as a driving force to open and close the roof, (3) the LDR as the light detector, (4) the detector TGS 2610 air humidity, and (5) water sensors to detect rain.

We developed the interactive multimedia lesson for Michelson Interferometer experiment to compare learning achievement between students who learn with and without the interactive multimedia and to study student’s satisfaction of the interactive multimedia lesson. Michelson Interferometer experiment is the lesson in the Intermediate Physics Laboratory for the second year of Applied Physics students of the Rajamangala University of Technology Thanyaburi. In this experiment, students have to count numbers of light fringes to determine the wavelength of He-Ne laser. We also developed a light counting device providing better experiment results with only 0.032% error compared to counting only by eyes. The efficiency of the interactive multimedia lesson evaluated by 3 experts both in content and production technique of the courseware was 4.45 meaning that the developed the Interactive Multimedia lesson was qualified at a good level. The Interactive Multimedia had the effectiveness at 92.12:80.38 which was higher than standard criteria set (80:80). The post-test scores of students who studied with interactive multimedia were significantly higher than the pre-test score at .05 level, and the student’s satisfaction of the interactive multimedia lesson was 4.25 which students most preferred the Interactive Multimedia Michelson interferometer experiment at a good level.

A fast-acting Cherenkov light detector with a high temporal resolution is described. The interest in such extensive air shower detectors is due to the need for more precise measurements of the Cherenkov pulse shape. The efficiency of the integral Cherenkov detector is demonstrated.

A simple method for measuring and evaluation of nonlinearity of the photomultiplier response efficiency using two controlled noncalibrated light sources is presented. The accuracy of the response efficiency nonlinearity evaluation and its linearization procedure was found to be 0.15%. As was shown, photomultiplier nonlinearity led to nonproportional distortions of photoelectronic estimates.

Because of their advantages, including easy tunability of optical and electrical properties by tailoring the molecular structure, flexibility, and compatibility with a low-temperature fabricating process, the use of organic semiconductors (OSCs) as active layers has shown strong competitiveness as candidates for use in next-generation high-sensitivity organic photodetectors (OPDs). Infrared (IR) OPDs that are sensitive to illumination at wavelengths higher than 780 nm have been rapidly developed in recent years driven by potential applications such as remote control, night vision, and imaging as well as biomedical monitoring. In this review, after a brief illustration of the mechanisms, we summarize the recent advances in high-performance IR organic photodiodes (OPDIs) and organic phototransistors (OPTs). We will highlight the state-of-the-art protocols for constructing qualified IR OPDs, including new OSCs with excellent photoelectric properties, optimization of active-layer-fabrication processes, and novel device architectures. Thereafter, we will discuss the IR organic light detector as a platform for integrated applications, such as health monitoring, spectrometric analysis, and electronic eyes. This review aims to provide readers with a deeper understanding of the design of future IR OPDs and IR-OPD-based integrated practices.

This study aims at exploring a simple and quantitative method for non-destructive monitoring of the myoglobin redox forms inside of beef. The modified Beer–Lambert law was employed to derive an equation that delineates a relationship between attenuance differences and oxy-, deoxy-, and met-myoglobin proportions. An experiment with forty-three well-bled muscle beef samples during 7 days of storage was performed to validate the equation. Firstly, the reflection spectra were collected from the beef samples using a probe consisting of a light source and a light detector. Secondly, the attenuance differences, A630-615 and A578-567, were calculated from the measured spectra. Finally, these attenuance differences were placed into the derived equation to determine the proportions of the three myoglobin redox forms. Both the met-myoglobin proportion and meat oxygenation computed via the attenuance differences established a strong correlation with the ones estimated using the whole spectrum (R(2) > 0.88). The experimental results suggest the potential of using the attenuance at five wavelengths (524, 567, 578, 615, and 630 nm) to monitor oxy-, deoxy-, and met-myoglobin inside of beef in a simple and fast manner with little to no sample preparation.

International audience; In this work we present how to fabricate large-area (15 cm 2 ), ultra-low threshold germanium bolometric photo-detectors and how to operate them to detect few (optical) photons. These detectors work at temperatures as low as few tens of mK and exploit the Neganov-Trofimov-Luke (NTL) effect. They are operated as charge-to-heat transducers: the heat signal is linearly increased by simply changing a voltage bias applied to special metal electrodes, fabricated onto the germanium absorber, and read by a (NTD-Ge) thermal sensor. We fabricated a batch of five prototypes and ran them in different facilities with dilution refrigerators. We carefully studied how impinging spurious infrared radiation impacts the detector performances, by shining infrared photons via optical-fiber-guided LED signals, in a controlled manner, into the bolometers. We hence demonstrated how the radiation-tightness of the test environment tremendously enhances the detector performances, allowing to set electrode voltage bias up to 90 volts without any leakage current and signal-to-noise gain as large as a factor 12 (for visible photons). As consequence, for the first time we could operate large-area NTD-Ge-sensor-equipped NTL bolometric photo-detectors capable to reach sub 10-eV baseline noise (RMS). Such detectors open new frontiers for rare-event search experiments based on low light yield Ge-NTD equipped scintillating bolometers, such the CUPID neutrinoless double-beta decay experiment.

Comunicació presentada a EDULEARN2019, 11th International Conference on Education and New Learning Technologies (July 1-3, 2019, Palma, Mallorca, Spain). Nowadays, it is undeniable that the amount of technological devices is having a sharp increase all around us, with important benefits and repercussions for the society. Despite this, students are not used to knowing the basic principles of its operations. Hence, it is of utmost importance to approach undergraduate students to a practical example of a device they can find in their daily life. It is a fact that science is interconnected with multiple disciplines, such as Physics and Solid State Chemistry, Materials Science and Engineering. A good example of it is a smoke detector because it combines both optical and electrical behaviour. Such a device contains a chamber inside which there is an infrared LED (light-emitting diode) and a photodiode (light detector). When the path of light is interrupted by the smoke, according to the principle of light scattering, the smoke will scatter a fraction of light into the photodiode, activating the detector. Thus, detecting low levels of smoke is vital for preventing the fire expansion and occupants can get more time to escape from the premises. The main purpose of this work is to help students to understand the work mechanism of the LED and photodiode in basis of their material composition. In order to do that, a smoke detector is disassembled and its different parts are observed. After that, the microstructure and composition of them are fully analysed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques. With these experiments, students have gained knowledge about semiconductors materials and got a more accurate understanding of their role in these devices. All in all, this experience has allowed them to keep in contact during the whole study with three main concepts of Materials Science: composition, structure and properties. This fact make the work interesting not only from the point of view of students, but also for teachers of Inorganic Chemistry and Materials Science owing to its pedagogical character employing a Problem Based Learning.

Cryogenic detectors are excellent devices for rare event searches. Thanks to their low energy thresholds, these detectors are at the cutting edge for the investigations of light dark matter (DM). The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) experiment explores with high sensitivity the parameter space of low mass DM candidates, being the pathfinder in the sub-GeV/c$^2$ mass range. CRESST employs scintillating CaWO$_4$ crystals as target material operated at mK temperature. Thanks to the simultaneous read-out of heat, in the main absorber, and light, with an auxiliary cryogenic light detector, the background in the region of interest is strongly suppressed. In 2018, the first stage of CRESST-III data taking was successfully completed, achieving an unprecedented energy threshold for nuclear recoils, lower than 100 eV. New results of CRESST-III will be presented accompanied by a status update on the ongoing activities.

This project aims to develop a cryogenic system for a UHV (Ultra-High Vacuum) manipulator that is currently under development in our group and that will be installed inside a low temperature scanning tunneling microscope (LT-STM). This advice will be used as a light detector to collect the Luminescence in the STM scan, and since the equipment will operate in low temperatures, it is necessary that this advice also operate in low temperatures so that it won't cause thermal instability which would prefent image acquisition due to thermal drifts.

This project aims to implement, test and improve a light detection system that will be installed in a Scanning Tunneling Microscope operating at Low Temperatures (LT-STM). This system is made of a parabolic mirror, a converging lens and an optical fiber bundle. The challenge will be to aligning these elements with sub-micrometric precision and develop alignment protocols to align the mirror with respect to the tunnel junction. Such procedures are crucial to the Young Investigators Project that funds the purchase of the LT-STM and which the final objective is the study of the luminescence of nanostructured semiconductors.

In this fast world we should need to know the blood group and type. So quick and perfect identification of blood sample is very important during the urgent situation. This future proposal is to change the physical work in medical laboratories for identifying the blood sample. Usually, the blood group analysis is made in the laboratories and there are three types of blood group analyzing methods, they are ABO forward typing, ABO reverse typing and Rhesus type testing. In the laboratories ABO type and Rhesus type testing techniques are mainly used. In the ABO testing method is used to identify the blood sample group. In the Rhesus testing method is used to identify the positive and negative of blood group.Even though it is easy to identify the blood group of single sample blood, but when handling the large number of blood samples, it might lead to wrong analysis. In order to solve this problem and reducing the manual involvement and to get better reliable result, we design the machine which will automatically identify the blood group based on the application of Infra Red (IR) light source. When the IR light is focused towards the blood sample, the light intensity is changed due to the blood darkness. It will be sensed by the IR light detector. The blood group and type can be identified by the intensity value of the light.

Detailed theoretical analysis of the shape measurement of optical surfaces based on light reflection on the measured surface is provided. Relations are given for computing the parameters of the reflected beam on the measured surface and its record on the light detector. Deflectometric equation is derived for oblique incident beam on the measured surface and the method of its solution is given.

According to the requirement of small satellite, this paper designed a digital sun sensor which diaphragm is a V-shaped cross-section structure. Using Position Sensitive Detector (PSD) as the light detector, we designed the V-shaped cross-section structure based on the pinhole imaging principle. The sun sensor realized the accurate calculation for two axis sun angle of the sun sensor. The mechanical test, thermal test and testing of the sun sensor are designed and carried out. The mechanical test and thermal test results verify the stability of the sun sensor. Testing result shows that the detection angle can reach (120°)×(120°), and the attitude determination accuracy is better than 6” in the entire viewing field. The mass, volume and power consumption of the sun sensor is 0.177 kg, 78 mm×77 mm×21 mm and 0.25 W. The sun sensor has low power consumption, large viewing angle and high precision characteristics, which realized the sun sensor the miniaturization and meet the requirements of the micro satellite. Its performance has been verified in orbit.

Okadaic acid (OA) and saxitoxin (STX) are common marine toxins which can accumulate in shellfish and affect human health through the food chain. A convenient and efficient method is urgently required to perform on-site detection of marine toxins to avoid frequent poisoning incidents. In this work, a smartphone-based system cooperating with competitive immunoassay strips was designed for rapid on-site detection of OA and STX. The smartphone was employed as a light detector for image acquisition and data processing. The 3D-printed portable accessory of the smartphone was utilized to fix the test strips. The homemade APP – iStrip used the pixel scan to obtain the valley value of the pixel curve as the output of the strip. The strip analytical method was easy to operate with a detection limit of 2.800 ng ml−1 for OA and 9.808 ng ml−1 for STX. Moreover, with the optimization of the antigen–antibody ratio on the strip, it provided quantitative analysis of OA and STX in the range of 3–20 ng ml−1 and 10–100 ng ml−1, respectively. Taking advantage of the smartphone and biochemical analysis, the strip analytical system will be a promising tool for on-site rapid detection of these two toxins.