Wyniki wyszukiwania - BazTech

1

Sterowany elektronicznie zasilacz z kompensacją temperatury do krzemowych fotopowielaczy (SiPM)

Matajek Tomasz, Mosorov Volodymyr

Przegląd Elektrotechniczny

|

2022

|

R. 98, nr 3

9--13

PL

W artykule przedstawiono zasadę działania, projekt i sposób obliczania elementów zasilacza do układów krzemowych fotopowielaczy (SiPM). Zasilacz jest skompensowany termicznie i wyposażony w analogowe wejście do regulacji napięcia wyjściowego. Podano i omówiono wyniki testów zbudowanego egzemplarza.

EN

This article presents the design, principle of operation and the method of calculating component values of power supply designed for silicon photomultipliers (SiPM). The power supply is thermally compensated and equipped with an analog input to regulate the output voltage. The results of the tests of the constructed prototype are presented and discussed.

2

A new brain dedicated PET scanner with 4D detector information

Gonzalez-Montoro Andrea, Barbera Julio, Sanchez David, Mondejar Alvaro, Freire Marta, Diaz Karel, Lucero Alejandro, Jimenez-Serrano Santiago, Alamo Jorge, Morera-Ballester Constantino, Barrio John, Cucarella Neus, Ilisie Victor, Moliner Laura, Valladares Celia, Gonzalez Antonio J., Prior John, Benlloch Jose M.

Bio-Algorithms and Med-Systems

|

2022

|

Vol. 18, no. 1

107--119

EN

In this article, we present the geometrical design and preliminary results of a high sensitivity organspecific Positron Emission Tomography (PET) system dedicated to the study of the human brain. The system, called 4D-PET, will allow accurate imaging of brain studies due to its expected high sensitivity, high 3D spatial resolution and, by including precise photon time of flight (TOF) information, a boosted signal-to-noise ratio (SNR). The 4D-PET system incorporates an innovative detector design based on crystal slabs (semi-monolithic) that enables accurate 3D photon impact positioning (including photon Depth of Interaction (DOI) measurement), while providing a precise determination of the photon arrival time to the detector. The detector includes a novel readout system that reduces the number of detector signals in a ratio of 4:1 thus, alleviating complexity and cost. The analog output signals are fed to the TOFPET2 ASIC (PETsys) for scalability purposes. The present manuscript reports the evaluation of the 4D-PET detector, achieving best values 3D resolution values of < 1,6 mm (pixelated axis), 2.7±0.5 mm (monolithic axis) and 3.4±1.1 (DOI axis) mm; 359 ± 7 ps coincidence time resolution (CTR); 10.2±1.5 % energy resolution; and sensitivity of 16.2% at the center of the scanner (simulated). Moreover, a comprehensive description of the 4D-PET architecture (that includes 320 detectors), some pictures of its mechanical assembly, and simulations on the expected image quality are provided.

3

Application of the silicon photomultiplier for fluorescence photobleaching measurement

Mik Ł., Kucewicz W.

Science, Technology and Innovation

|

2017

|

Vol. 1, no. 1

11--16

EN

In the paper a measurement method of fluorescence intensity reduction (called photobleaching) caused by excitation light was presented. Intensity of fluorescence light was measured by silicon photomultiplier (SiPM) – sensor which allows single photons detection. It has more compact dimensions and lower bias voltage in comparison to photomultiplier tube, presently used in many laboratory devices. Standard photometric cuvettes with a capacity of 1.6 ml and optical path length of 10 mm were used for the measurements. Sodium fluoresceinate dissolved in 10 mM TRIS buffer at pH 8.5 was used as the fluorescent dye. The solution was tested at a concentration of 100 μg per ml with constant excitation light from LED source over the time of measurement.

4

Regulated common-gate TIA with noise improvement for radiation detectors

Dias D. C, Melo F. S, Oliveira L. B., Oliveira J. P.

International Journal of Microelectronics and Computer Science

|

2014

|

Vol. 5, nr 2

69--80

EN

A Transimpedance Amplifier (TIA) is a device which performs current-voltage conversion and signal shaping. The most commonly used solution is an Avalanche Photo-Diode (APD) as radiation detector with a feedback TIA. Recently, Silicon Photo-Multipliers (SiPMs), have proven to be good alternatives. The main objective in this paper is to show, evaluate and compare the behavior of a regulated common-gate (RCG) TIA when the light sensitive device is an APD or a SiPM. We will also present two alternative circuits based on the RCG topology. The first can be resumed to the insertion of a transistor, responsible for an improvement in the output noise response of the TIA. This solution proves itself to be a good alternative, since it will improve the Signal-to-Noise Ratio (SNR) of the circuit by around 3 dB, with negligible penalty in consumption (only 2%). The second alternative will be a proposed differential version of the RCG topology, in which the first solution will be included. These two latter solutions will only be tested with a SiPM at the input. We will also study the RCG topology in a RF front-end, providing there is a passive mixer at the TIA’s input. The proposed circuits are simulated with standard CMOS technology (UMC 130 nm), from a 1.2 V supply.

5

Silicon photomultiplier gain compensation algorithm in multidetector measurements

Baszczyk M., Dorosz P., Głąb S., Kucewicz W., Mik Ł., Sapor M.

Metrology and Measurement Systems

|

2013

|

Vol. 20, nr 4

655--666

EN

The paper stresses the issue of strong temperature influence on the gain of a Silicon Photomultiplier (SiPM). High sensitivity of the detector to light (single photons) requires stable parameters during measurement, including gain. The paper presents a method of compensating the change of gain caused by temperature variations, by adjusting a suitable voltage bias provided by a precise power module. The methodology of the research takes in account applications with a large number of SiPMs (20 thousand), explains the challenges and presents the results of the gain stabilization algorithm.

6

Fluorescence detection in microfluidics systems

Szczypiński R., Mik Ł., Kruk J., Baszczyk M., Dorosz P., Głąb S., Pijanowska D. G., Kucewicz W.

Przegląd Elektrotechniczny

|

2012

|

R. 88, nr 10b

88-91

EN

In this paper, two optical detection systems – first based on the tube and the second one on the silicon photomultiplier are described. The detection system was tested for fluorescent dyes - sodium fluoresceinate and resorufin excitated in two systems: static and dynamic i.e. in PMMA cuvettes and PDMS made microchannels, respectively. Sources of excitation light were 488 and 532 nm wavelength laser diodes and blue/green LEDs (light emitting diodes). In the experiment tube and silicon photomultipliers applied in the above-mentioned systems were compared.

PL

Jako fotodetektory w układach mikroprzepływowych stosuje się urządzenia takie jak matryce CMOS, fotodiody lawinowe czy fotopowielacze lampowe. W ostatnim czasie prowadzone są intensywne badania nad zastosowaniem fotopowielaczy krzemowych jako fotodetektorów. Jest to spowodowane między innymi względami ekonomicznymi oraz dużo łatwiejszą ich mobilnością. W naszym artykule zaprezentowane zostały porównawcze wyniki badań dla dwóch fotopowielaczy – lampowego oraz krzemowego w zastosowaniach w układach mikrofluidycznych.

7

Method of temperature fluctuations compensation in the silicon photomultiplier measurement system

Baszczyk M., Dorosz P., Głąb S., Kucewicz W., Mik Ł., Sapor M.

Elektronika : konstrukcje, technologie, zastosowania

|

2012

|

Vol. 53, nr 7

64-67

EN

This paper presents the method for the compensation of the temperature fluctuations in the measurement system based on the Silicon Photomultipliers (SiPM). Temperature has very strong influence on the gain of the detectors. Because single photons are detected and the system is very sensitive, its parameters have to be steady during the measurements. Temperature is being stabilized by changeable bias voltage of the detector. This paper describes how the algorithm of compensation has been determined during series of measurements and presents first results of temperature compensation.

PL

Artykuł opisuje metodę kompensacji zmian temperatury w systemach pomiarowych zawierających krzemowe fotopowielacze. Temperatura ma duży wpływ na wzmocnienie krzemowego fotopowielacza. Ponieważ urządzenie to jest bardzo czułe i potrafi mierzyć pojedyncze fotony, jego parametry muszą być kontrolowane podczas pomiaru. Temperatura jest stabilizowana przez zmiany napięcia polaryzacji. Artykuł prezentuje opis opracowania metody kompensacji na podstawie pomiarów oraz pierwsze wyniki kompensacji temperatury.

8

Silicon photomultiplier as fluorescence light detector

Mik Ł., Kucewicz W., Barszcz J., Sapor M., Głąb S.

Elektronika : konstrukcje, technologie, zastosowania

|

2011

|

Vol. 52, nr 12

61-65

EN

This paper presents an efficient measurement system for a low-level light detection, emitted by fluorescent dye. The system setup and measuring method has been discussed. Silicon photomultiplier, which is called Multi Pixel Photon Counter developed by Hamamatsu, has been used as a light detector. Tests has been done for fluorescein and resorufin specimens in 1.5 ml volume PMMA (Polymethyl Methacrylate) cuvettes positioned in a specially designed optical system. Solutions of this dyes were prepared in TRIS buffer with pH factor equal 8. Range of concentrations which has been used for measurements is from 1ug/ml to about 1 pg/ml.

PL

Artykuł przedstawia efektywny system pomiarowy do detekcji światła fluorescencyjnego o niskim natężeniu. Została w nim omówiona konstrukcja systemu oraz metoda pomiarowa. Jako czujnik światła fluorescencyjnego użyty został fotopowielacz krzemowy produkowany przez firmę Hamamatsu. Testy wykonano na próbkach fluoresceiny i rezorufiny umieszczonych w kuwetkach PMMA o pojemności 1,5 ml. Roztwory tych barwników przygotowano w roztworze TRIS o czynniku pH = 8. Stężenia barwników w roztworach, wykorzystane podczas pomiarów zawierają się w przedziale od 1ug/ml do około 1 pg/ml.

9

Four channels data acquisition system for silicon photomultipliers

Baszczyk M., Dorosz P., Głąb S., Kucewicz W., Sapor M.

Elektronika : konstrukcje, technologie, zastosowania

|

2011

|

Vol. 52, nr 12

28-31

EN

This paper presents data acquisition system for Silicon Photomultiplier (SiPM), with four channels front-end ASIC implemented in 0.35 µm CMOS AMS technology. The signal from SiPM is shaped in front-end ASIC, converted to a digital value and processed in FPGA. The paper discusses principles of work, results of device measurements and data analysis.

PL

Artykuł ten prezentuje system akwizycji danych dla krzemowych fotopowielaczy (SiPM), który wykorzystuje czterokanałowy układ scalony ASIC zaimplementowany w technologii CMOS AMS 0,35 µm. Sygnał pochodzący z SiPM jest kształtowany w układzie ASIC, następnie konwertowany na postać cyfrową i poddawany dalszej obróbce w układzie FPGA. Artykuł omawia zasadę działania systemu, wyniki przeprowadzonych badań oraz analizę danych.