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1

IR detection module with integrated real-time FIR filter implemented in FPGA

Achtenberg Krzysztof, Mikołajczyk Janusz, Bielecki Zbigniew

International Journal of Electronics and Telecommunications

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2024

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Vol. 70, No. 1

175--182

EN

Infrared detectors are usually characterized by 1/f noise when operating with biasing. This type of noise significantly reduces detection capabilities for low-level and slow signals. There are a few methods to reduce the influence of 1/f noise, like filtering or chopper stabilization with lock-in. Using the first one, a simple 1st-order analog low-pass filter built-in amplifier usually cuts off 1/f noise fluctuations at low frequencies. In comparison, the stabilization technique modulates the signal transposing to a higher frequency with no 1/f noise and then demodulates it back (lock-in amplifiers). However, the flexible tuned device, which can work precisely at low frequencies, is especially desirable in some applications, e.g., optical spectroscopy or interferometry. The paper describes a proof-of-concept of an IR detection module with an adjustable digital filter taking advantage of finite impulse response type. It is based on the high-resolution analog-to-digital converter, field-programmable gate array, and digital-to-analog converter. A microcontroller with an implemented user interface ensures control of such a prepared filtering path. The module is a separate component with the possibility of customization and can be used in experiments or applications in which the reduction of noises and unexpected interferences is needed.

2

Theoretical study of back-to-back avalanche photodiodes for dual-band infrared applications

Manyk Tetiana, Majkowycz Kinga, Rutkowski Jarosław, Martyniuk Piotr

Opto-Electronics Review

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2023

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Vol. 31, No. 2

art. no. e145093

EN

The dual-band avalanche photodiode (APD) detector based on a HgCdTe material system was designed and analysed in detail numerically. A theoretical analysis of the two-colour APD intended for the mid wavelength infrared (MWIR) and long wavelength infrared (LWIR) ranges was conducted. The main purpose of the work was to indicate an approach to select APD structure parameters to achieve the best performance at high operating temperatures (HOT). The numerical simulations were performed by Crosslight numerical APSYS platform which is designed to simulate semiconductor optoelectronic devices. The current-voltage characteristics, current gain, and excess noise analysis at temperature T = 230 K vs. applied voltage for MWIR (U = 15 V) and LWIR (U = –6 V) ranges were performed. The influence of low and high doping in both active layers and barrier on the current gain and excess noise is shown. It was presented that an increase of the APD active layer doping leads to an increase in the photocurrent gain in the LWIR detector and a decrease in the MWIR device. The dark current and photocurrent gains were compared. Photocurrent gain is higher in both spectral ranges.

3

Low-temperature growth of GaSb epilayers on GaAs (001) by molecular beam epitaxy

Benyahia D., Kubiszyn Ł., Michalczewski K., Kębłowski A., Martyniuk P., Piotrowski J., Rogalski A.

Opto-Electronics Review

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2016

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Vol. 24, No. 1

40--45

EN

Non-intentionally doped GaSb epilayers were grown by molecular beam epitaxy (MBE) on highly mismatched semi-insulating GaAs substrate (001) with 2 offcut towards (110). The effects of substrate temperature and the Sb/Ga flux ratio on the crystalline quality, surface morphology and electrical properties were investigated by Nomarski optical microscopy, X-ray diffraction (XRD) and Hall measurements, respectively. Besides, differential Hall was used to investigate the hole concentration behaviour along the GaSb epilayer. It is found that the crystal quality, electrical properties and surface morphology are markedly dependent on the growth temperature and the group V/III flux ratio. Under the optimized parameters, we demonstrate a low hole concentration at very low growth temperature. Unfortunately, the layers grown at low temperature are characterized by wide FWHM and low Hall mobility.

4

Przetwarzanie sygnału z wielokanałowych detektorów piroelektrycznych

Jasek K., Puton J., Mazurek B., Juszczuk R.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 7

130-134

PL

W pracy przedstawiono różne sposoby przetwarzania sygnału z czterokanałowego detektora piroelektrycznego z filtrami interferencyjnymi, przeznaczonego do pomiaru CO, CO₂ , SO₂ oraz filtrem referencyjnym. Detektor pracował w analizatorze NDIR przeznaczonym do oznaczania składu gazów spalinowych. Aby wybrać odpowiednią metodę obróbki sygnału oraz określić wpływ różnych czynników na wyniki pomiarów wyznaczono charakterystyki stężeniowe analizatora dla różnych mocy źródła promieniowania. Stwierdzono, że najlepsze rezultaty otrzymuje się posługując sygnałem zredukowanym S = 1 - UIU₀, gdzie U i U₀ oznaczają odpowiednio sygnał detektora w trakcie pomiaru oraz zerowania przyrządu. Uwzględnienie kanału referencyjnego nie wpływa w istotnym stopniu na dokładność oznaczeń. Zbadano różne zależności, aproksymujące sygnał detektora w funkcji stężenia mierzonego gazu. Dla wszystkich badanych gazów najlepsze dopasowanie do wartości doświadczalnych uzyskano dla zależności S = b [1-exp(-aCⁿ)j, gdzie C oznacza stężenie gazu; a, b, n współczynniki wyznaczane z danych doświadczalnych.

EN

Different ways of signal processing from multichannel pyroelectric detector with interference filters designed for measurements CO, CO₂, SO₂ and reference filter is presented in the paper. The detector operates in NDIR analyzer, dedicated to determine composition of exhaust gases. To select the best method of signal processing and determine the influence of various factors on measurement results, concentration characteristics were found at different radiation source power. The best results were obtained at relative signal S = 1 – U/U₀, where U and U₀ stand for detector signal during the measurement and zeroing, respectively. The precision of measurements was not considerably improved by using the reference channel. Some relationships between the detector signal and gas concentration were examined. In all casesthe bestfitting of signal to experimental values was obtained for the function S = b [1-exp(-aCⁿ)], where C is gas concentration, a, b, n are experimental coefficients.

5

System do pomiarów charakterystyk widmowych detektorów promieniowania optycznego w szerokim zakresie temperatury

Ćwirko R., Ćwirko J.

Biuletyn Wojskowej Akademii Technicznej

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2009

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Vol. 58, nr 2

407-417

PL

W artykule przedstawiono zaprojektowany i wykonany w Wojskowej Akademii Technicznej (WAT) system do pomiarów charakterystyk widmowych detektorów promieniowania optycznego UV, VIS i IR w szerokim zakresie temperatury od 10 K do 450 K. System pomiarowy umożliwia także badanie wpływu temperatury na charakterystyki szumowe detektorów.

EN

The paper presents an integrated system, developed at the Military University of Technology (MUT), used for measurements of spectral characteristic of UV, VIS, and IR detectors. The setup provides also the possibility of noise measurements in a wide temperature range - from 10 K to 450 K.

6

Wavelength and polarization selective multi-band tunnelling quantum dot detectors

Perera A. G. U., Ariyawansa G., Apalkov V. M., Matsik S. G., Su X. H., Chakrabarti S., Bhattacharya P.

Opto-Electronics Review

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2007

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Vol. 15, No. 4

223-228

EN

The reduction of the dark current without reducing the photocurrent is a considerable challenge is developing far-infrared (FIR)/terahertz detectors. Since quantum dot (QD) based detectors inherently show low dark current, a QD-based structure is an appropriate choice for terahertz detectors. The work reported here discusses multi-band tunnelling quantum dot infrared photo detector (T-QDIP) structures designed for high temperature operation covering the range from mid- to far-infrared. These structures grown by molecular beam epitaxy consist of a QD (InGaAs or InAlAs) placed in a well (GaAs/AlGaAs) with a double-barrier system (AlGaAs/InGaAs/AlGaAs) adjacent to it. The photocurrent, which can be selectively collected by resonant tunnelling, is generated by a transition of carriers from the ground state in the QD to a state in the well coupled with a state in the double-barrier system. The double-barrier system blocks the majority of carriers contributing to the dark current. Several important properties of T-QDIP detectors such as the multi-colour (multi-band) nature of the photoresponse, the selectivity of the operating wavelength by the applied bias, and the polarization sensitivity of the response peaks, are also discussed.

7

Optoelektronika profilem działalności polskiej firmy high-tech

Rzeczkowski M., Brudnowski M., Paliwoda R.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 5

18-27

PL

Przedstawiono problemy występujące przy konstruowaniu urządzeń optoelektronicznych z detektorami podczerwieni, produkowanymi przez polską firmę VIGO System S.A. Zaprezentowano profil standardowej produkcji firmy i specyfikę współpracy z klientem nad projektami wykonywanymi wg indywidualnych wymagań, zwłaszcza wybrane projekty zrealizowane przez Wydział Elektroniki ww. firmy w ostatnich kilku latach. Szczególnie omówiono współpracę wzmacniaczy transimpedancyjnych z wysoko rezystancyjnymi źródłami sygnału o znacznej pojemności.

EN

This article presents a short scope of IR applications against a back-ground of Vigo - System's activity. Apart of standard IR products, a customer oriented approach has been described. It covers non-typical solutions designed according to our customer's requirements. Special attention has been paid to IR detectors and current mode (transimpedance) amplifiers, including selected methods of matching them. The article shows also some difficult problems faced by a designer, when high resistance IR detectors are used. In the final part of this work the prospects of development of the Polish IR market have been discussed.

8

Suppression of Auger generation as the way to perfect detection of IR radiation

Piotrowski J.

Problemy Techniki Uzbrojenia

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2002

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R. 31, z. 82

57--68

EN

Performance of infrared photodetectors operating at high temperatures is limited by the noise due to statistical nature of thermal generation of charge carriers in semiconductors. Auger processes are responsible for thermal generation in narrow gap semiconductors. Various ways to reduce Auger processes are considered including optimised doping, non-equilibrium mode of operations and the use of band gap engineered materials. The suppression of Auger processes will lead to perfect detection of long wavelength detection without cooling. Some applications of Auger suppressed devices are discussed including heterodyne receivers, IR imagers and detectors for optical communications.

9

Device physics and focal plane array applications of QWIP and MCT

Tidrow M. Z., Beck W. A., Clark W. W., Pollehn H. K., Little J. W., Dhar N. K., Leavitt R. P., Kennerly S. W., Beekman D. W., Goldberg A. C., Dyer W. R.

Opto-Electronics Review

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1999

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Vol. 7, No. 4

283-296

EN

Infrared (IR) sensor technology is critical to many commercial and military defense applications. Traditionally, cooled infrared material systems such as indium antimonide, platinum silicide, mercury cadmium telluride (MCT), and arsenic doped silicon (Si:As) have dominated infrared detection. Improvement in surveillance sensors and interceptor seekers requires size, highly uniform, and multicolor IR focal plane arrays involving medium wave, long wave, and very long wave IR (VLWIR) regions. Among the competing technologies are the quantum well infrared photodetectors (QWIPs) based on lattice matched or strained III-V material systems. This paper discusses cooled IR technology with emphasis on QWIP and MCT. Detais will be given concerning device physics, material growth, device fabrication, device performance, and cost effectiveness for LWIR, VLWIR, and multicolor focal plane array applications.