Temat: semiconductor laser

Skocz do pozycji: 1.

Tytuł:: Design of a measurement stand with DAQ card and semiconductor laser for recording acoustic signals
Autorzy:: Krawiecki, Z.
Gloger, D.
Tematy:: acoustic signal
recording
photodetector
semiconductor laser; Pokaż więcej
Wydawca:: Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Powiązania:: https://bibliotekanauki.pl/articles/97505.pdf Link otwiera się w nowym oknie
Opis:: This article describes the stage of work associated with the implementation of a program- controlled measuring stand for recording the acoustic signals. An attempt has been made for practical implementation of the stand that uses light from a semiconductor laser, modulated by acoustic wave to obtain the information transmitted by this wave. The authors decided to build the hardware construction of the stand with the use of: a PC which serves as the controller, a DAQ card, the light emitter set with a semiconductor laser and the light receiving set capable of processing the received signal into a form suitable for a DAQ card. Moreover, additional equipment used during the examination tests is also described. The software part of the stand includes: device drivers and an application written in LabVIEW environment. The functions of signal processing and analysis, graphical and numerical presentation of the data, recording to file and reading the stored data from a file are all implemented in the application. The achieved stage of a work has been confirmed by sample measurements.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: The use of the computer system of detection of the laser beam in the measurements of geometry of mine shafts
Autorzy:: Jaśkowski, W.
Tematy:: laser półprzewodnikowy
instalacje kanalizacyjne
semiconductor laser
sewer systems; Pokaż więcej
Wydawca:: Politechnika Warszawska. Wydział Geodezji i Kartografii
Powiązania:: https://bibliotekanauki.pl/articles/225514.pdf Link otwiera się w nowym oknie
Opis:: A huge progress in the laser technology, in particular the creation of the semiconductor laser, allows to see the method of laser plumbing as a method of the future which can replace mechanical plumbing. Therefore, the issues connected with the method of plumbing become more and more popular. The most important ones are: - directing the laser beam, - determining the center of the laser beam at the point of target (detection of the laser beam). The issue of the focus of the laser beam, thanks to the researches made in 1970 and 1980 and aimed to the use of the laser light in the measurements of the shafts, is practically resolved (Jóźwik 1994). The construction of many types of laser plummets (based on different operating principles), as well as the possibility of adapting the optical plummets to cooperate with the laser diode, enables to focus the laser beam with high precision. The second issue concerning the detection of the laser bean, limited so far the possibilities of applicability of this method. Currently, the most common method of detection is a visual method (used by PMG Katowice, ZG Rudna, ZG Polkowice) aimed to specify the center of the laser beam on the observation wheel with an accuracy of 3mm. There is also applied the photogrammetric method based on the digital photography used by DARTECH company from Ruda Śląska. These methods are either not very accurate (the visual method) or allowing to perform measurements only at selected levels of measurement (the photogrammetric method).
Dostawca treści:: Biblioteka Nauki

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na półce

Skocz do pozycji: 3.

Tytuł:: Phase space analysis of semiconductor laser dynamics
Autorzy:: Grześ, Paweł
Michalska, Maria
Świderski, Jacek
Tematy:: semiconductor laser
laser dynamics
phase space analysis
rate equations; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Powiązania:: https://bibliotekanauki.pl/articles/59112935.pdf Link otwiera się w nowym oknie
Opis:: The dynamics of semiconductor lasers are modelled in the time domain using a pair of differential equations known as rate equations. The analysis, based on temporal solutions of these equations, yields practical results utilised in various applications. Alternatively, an analysis employing the phase space method, a well-established analytical tool in applied mathematics, provides a more comprehensive perspective on semiconductor laser dynamics. The main purpose of this paper is to provide a detailed and intuitive introduction to phase space analysis in the context of semiconductor laser dynamics. The goal is to offer an easily comprehensible description of the mentioned method, placing emphasis on the graphical representation and physical interpretation of the results. The method effectiveness is shown through its application to selected practical problems. Furthermore, semiconductor laser dynamics can be treated as an illustrative example, showcasing the applicability of the method, which can be readily extended to other types of lasers or even more advanced dynamic systems.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Optical MIDO : Multiple Inputs-Digital Output : device
Autorzy:: Alaiz-Gudin, Antonio M.
González-Marcos, Ana P.
Tematy:: distributed feedback laser
multi quantum well
optical bistability
semiconductor laser; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Powiązania:: https://bibliotekanauki.pl/articles/2063884.pdf Link otwiera się w nowym oknie
Opis:: Advances in photonic technologies, with new processes and scopes of photonic integrated circuits, have generated a lot of interest as the field allows to obtain sensors with reduced size and cost and build systems with high interconnectivity and information density. In this work, answering the needs of photonic sensors that must be portable, more energy- efficient, and more accurate than their electrical counterparts, also with a view to the emerging field of neuromorphic photonics, a versatile device is presented. The proposed device makes use of the well-known advantages provided by optical bistability. By combining two distributed feedback-multi quantum well semiconductor laser structures, this new optical multiple inputs - digital output device offers various essential purposes (such as logic gates, wavelength detector and monitoring) with no need for specific manufacturing for each of them. Through a commercial computer-aided design tool, VPIphotonics™, the necessary characterization of proposed device is also described.
Dostawca treści:: Biblioteka Nauki

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na półce

Skocz do pozycji: 5.

Tytuł:: First vertical-cavity surface-emitting laser made entirely in Poland
Autorzy:: Gębski, Marcin
Śpiewak, Patrycja
Kołkowski, Walery
Pasternak, Iwona
Głowadzka, Weronika
Nakwaski, Włodzimierz
Sarzała, Robert P.
Wasiak, Michał
Czyszanowski, Tomasz
Strupiński, Włodzimierz
Tematy:: semiconductor laser
GaAs
gallium arsenide
optical communication
VCSEL
laser półprzewodnikowy
arsenek galu
komunikacja optyczna; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/2173617.pdf Link otwiera się w nowym oknie
Opis:: The paper presents the first vertical-cavity surface-emitting lasers (VCSELs) designed, grown, processed and evaluated entirely in Poland. The lasers emit at »850 nm, which is the most commonly used wavelength for short-reach (<2 km) optical data communication across multiple-mode optical fiber. Our devices present state-of-the-art electrical and optical parameters, e.g. high room-temperature maximum optical powers of over 5 mW, laser emission at heat-sink temperatures up to at least 95°C, low threshold current densities (<10 kA/cm2) and wall-plug efficiencies exceeding 30% VCSELs can also be easily adjusted to reach emission wavelengths of around 780 to 1090 nm.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: First vertical-cavity surface-emitting laser made entirely in Poland
Autorzy:: Gębski, Marcin
Śpiewak, Patrycja
Kołkowski, Walery
Pasternak, Iwona
Głowadzka, Weronika
Nakwaski, Włodzimierz
Sarzała, Robert P.
Wasiak, Michał
Czyszanowski, Tomasz
Strupiński, Włodzimierz
Tematy:: semiconductor laser
GaAs
gallium arsenide
optical communication
VCSEL
laser półprzewodnikowy
arsenek galu
komunikacja optyczna; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/2090716.pdf Link otwiera się w nowym oknie
Opis:: The paper presents the first vertical-cavity surface-emitting lasers (VCSELs) designed, grown, processed and evaluated entirely in Poland. The lasers emit at »850 nm, which is the most commonly used wavelength for short-reach (<2 km) optical data communication across multiple-mode optical fiber. Our devices present state-of-the-art electrical and optical parameters, e.g. high room-temperature maximum optical powers of over 5 mW, laser emission at heat-sink temperatures up to at least 95°C, low threshold current densities (<10 kA/cm2) and wall-plug efficiencies exceeding 30% VCSELs can also be easily adjusted to reach emission wavelengths of around 780 to 1090 nm.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: Irreversible blocking of polar excitations on frog sciatic nerve using semiconductor pulse laser irradiation
Autorzy:: Hirayama, Y.
Ishizuka, S.
Yamakawa, T.
Tematy:: irreversible blocking
semiconductor pulse Laser Irradiation
frog sciatic nerve; Pokaż więcej
Wydawca:: Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Powiązania:: https://bibliotekanauki.pl/articles/385078.pdf Link otwiera się w nowym oknie
Opis:: The final purpose of our research is to cripple the epileptogenic focus by laser irradiation. However, the effect of laser irradiation on brain nerves is not well known. In this paper, we observed laser irradiation to the transmission of action potential of a bullfrog sciatic nerve in the experiment. In addition the marginal amplitude of laser energy is obtained. The bullfrog nerve preparations were stimulated supramaximal intensity pulse. The pulse width and the pulse interval are 1 msec and 1 sec, respectively. A semiconductor pulse laser irradiation (the wavelength, the pulse width and the frequency are 808 nm, 990 µsec and 50 Hz, respectively) was employed until when the amplitude of the action potential decreases to 10 %. The laser light was irradiated to the portion between two electrode pairs for recording. The energy of the laser is variable between 13.9- 202.5 mJ/cm2. The laser irradiator is connected to an optical fiber whose diameter is 1 mm. The action potential of the sciatic nerve is observed at 1 day after in order to confirm irreversibility. The experiment was delivered by the laser pulse, the energy of which over 32.9 mJ/cm2. The peak of action potential was decreased gradually by laser irradiation with depending on the time of irradiation. The time to blocking is reciprocally proportional to laser energy. At a day after the experiment, the action potential was not recovered. This result shows the laser irradiation give irreversible blocking to polar excitations. We observed the frog sciatic nerve is damaged by laser irradiation. The results show a possibility that the epileptogenic focus can be crippled by laser irradiation. We are going to have more experiments and obtain important laser parameters. In the future, the experiment and the result are expanded using rat brain and applied human surgery.
Dostawca treści:: Biblioteka Nauki

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na półce

Skocz do pozycji: 8.

Tytuł:: Influence of Pumping Beam Width on VECSEL Output Power
Autorzy:: Sokół, A. K.
Sarzała, R. P.
Tematy:: VECSEL
SDL
semiconductor disk laser
simulation
numerical modeling
power scaling; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/226018.pdf Link otwiera się w nowym oknie
Opis:: The paper is devoted to a numerical analysis of an influence of a pumping beam diameter on output power of optically pumped vertical-external-cavity surface-emitting lasers. Simulations have been carried out for a structure with a GaInNAs/GaAs active region operating at 1.32 μm. Various assembly configurations have been considered. Results obtained show that laser power scaling is strongly affected by thermal properties of the device.
Dostawca treści:: Biblioteka Nauki

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na półce

Skocz do pozycji: 9.

Tytuł:: Możliwości modyfikacji charakterystyk promieniowania laserów półprzewodnikowych przez superpozycję naprężeń w warstwie aktywnej
Materiały Elektroniczne 2002 T.30 nr 4
Możliwości modyfikacji charakterystyk promieniowania laserów półprzewodnikowych przez superpozycję naprężeń w warstwie aktywnej = On the possibility of modification of semiconductor laser emission characteristics by strain superposition in active region
Autorzy:: Maląg Andrzej
Wydawca:: ITME
Powiązania:: Electronic Materials
Materiały Elektroniczne T.30 nr 4
Opis:: Bibliogr. s. 52-53
22-54 s. : il. 24 cm.
Dostawca treści:: RCIN - Repozytorium Cyfrowe Instytutów Naukowych

Książka

na półce

Skocz do pozycji: 10.

Tytuł:: Thermal problems in arsenide VECSELs
Zagadnienia cieplne w arsenkowych laserach typu VECSEL
Autorzy:: Sokół, A.
Sarzała, R.
Tematy:: VECSEL
laser półprzewodnikowy
gospodarka cieplna
GaInNAs
semiconductor disk laser
heat management
thermal management; Pokaż więcej
Wydawca:: Politechnika Łódzka. Wydawnictwo Politechniki Łódzkiej
Powiązania:: https://bibliotekanauki.pl/articles/296424.pdf Link otwiera się w nowym oknie
Opis:: Different aspects of thermal management of GaAs-based vertical-external-cavity surface-emitting lasers (VECSELs) are described and analyzed by example of typical configurations of GaInNAs/GaAs multiple-quantum-well (MQW) VECSEL. Simulations of two-dimensional heat-flux spreading within investigated structures have been carried out with the aid of the self-consistent thermal finite-element method. Influence of pumping-beam and heat spreader properties on maximal temperature increase have been studied and different heat management techniques have been compared.
W pracy zostały opisane i przeanalizowane wybrane aspekty dotyczące własności cieplnych optycznie pompowanych laserów półprzewodnikowych o emisji powierzchniowej z zewnętrzną pionową wnęką rezonansową (VECSELs, ang. vertical-external-cavity surface-emitting lasers) na podłożu z GaAs. Obliczenia wykonano dla typowych konfiguracji montażowych lasera typu VECSEL z obszarem czynnym w postaci wielokrotnej studni kwantowej wykonanej w systemie materiałowym GaInNAs/GaAs. Do symulacji dwuwymiarowego rozpływu ciepła wykorzystano samouzgodniony model cieplny oparty na metodzie elementów skończonych (MES) , przy pomocy którego porównano własności cieplne poszczególnych struktur oraz określono wpływ parametrów wiązki pompującej (moc, średnica) i heat spreadera (przewodność cieplna, grubość) na maksymalny przyrost temperatury w ich wnętrzach.
Dostawca treści:: Biblioteka Nauki

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