Articolele autorului Virgil-Florin Duma
Link la profilul stiintific al lui Virgil-Florin Duma

7th SRLS-SPIE International Conference on Lasers In Medicine

We kindly invite you to take part in this event organized by the  Romanian Society for Lasers in Dentistry (July 13th-16th, 2017, Timisoara, Romania). Site of the event: http://lasercongress-srls.com/ The program of the Conference is organized on two sections: (i) Lasers in medicine and dentistry: Clinical applications; (ii) Optics, photonics, and biomedical imaging (with a focus on Optical Coherence Tomography). The International Society for Optics

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Assessment of the sealant/tooth interface using optical coherence tomography

Sealant materials are typically employed in dentistry in order to prevent the development of cavities on the teeth. They prevent bacterial adhesion to enamel, thus arresting the development of demineralization and of caries. In this study the critical zone of the interface between different sealant materials and the results of the dental work for the teeth processed were investigated ex vivo using Swept Source (SS) Optical Coherence Tomography (OCT).

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Surface imaging of metallic material fractures using optical coherence tomography (OPEN ACCESS)

We demonstrate the capability of optical coherence tomography (OCT) to perform topography of metallic surfaces after being subjected to ductile or brittle fracturing. Two steel samples, OL37 and OL 52, and an anti-friction Sn-Sb-Cu alloy were analyzed. Using an in house built swept source (SS) OCT system height profiles were generated for the surfaces of the two samples. Based on such profiles, it can be concluded that the first two samples were

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Design and testing of prototype handheld scanning probes for optical coherence tomography (OPEN ACCESS)

Three simple and low-cost configurations of handheld scanning probes for optical coherence tomography (OCT) have been developed. Their design and testing for dentistry applications are presented. The first two configurations were built exclusively from available off-the-shelf optomechanical components, which, to the best of our knowledge are the first designs of this type. The third configuration includes these components in an optimized and ergonomic

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Prototypes and modulation functions of classical and novel configurations of optical chopper wheels

Optical choppers with rotating wheels are some of the most used macroscopic optomechatronic devices for the controlled modulation, attenuation or obscuration of light in a wide area of applications. We discuss and compare the modulation functions produced by two types of chopper wheels: the classical device, with windows with linear edges, and the eclipse chopper (with windows with circular edges) that, to the best of our knowledge, we have introduced.

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SRLS – SPIE Lasers in Medicine Conference [ISI] in Timisoara, Sept. 19-21, 2013

Cea de a 5-a Editie a Conferintei Internationale "Lasers in Medicine" (ICLM) va avea loc in Timisoara, in 19-21 Sept. 2013, in organizarea SRLS (Societatea Romana de Laseri in Stomatologie, www.srls.ro), sub egida WFLD (World Federation for Lasers in Dentistry) si cu participarea SPIE (Society of Optical Engineering, USA, www.spie.org) - cu Sectiuni de Laseri in Medicina, dar si de Optica si Optomecatronica,Optical Coherence Tomography si Basic Science

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Experimental investigations of the scanning functions of galvanometer-based scanners with applications in OCT

We analyse three most common profiles of scanning functions for galvanometer-based scanners (GS), the sawtooth, triangular and sinusoidal functions. They are determined experimentally with regard to the scan parameters of the input signal (i.e. frequency and amplitude). We study the differences of the output function of the GS measured as the positional error of the oscillatory mirror from the ideal function given by the input signal of the device.

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Fulbright Science and Technology 2012

Comisia Fulbright din Romania anunta deschiderea competitiei International Fulbright Science and Technology Award 2012, prin care se acorda studentilor, absolventilor si masteranzilor romani de la universitati de stat si private burse doctorale in domeniul ingineriei, tehnologiei si stiintelor exacte, la universitati de elita din Statele Unite ale Americii. Bursa vizeaza discipline precum: Aeronautica, Agronomie, Astronomie/Stiinte planetare, Biologie,

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Optical choppers with circular-shaped windows: Modulation functions

In this paper the non-linear process of light modulation performed by optical choppers is studied. The real functions of the transmitted flux, with transition portions are derived, in contrast to approximate approaches, of flux functions considered as series of rectangular impulses. An exact mathematical model of the dynamic phenomenon is thus achieved. Top-hat light beam distributions are considered. We are developing in this paper a new type of

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Optimal Scanning Function of a Galvanometer Scanner for an Increased Duty Cycle

We study different possible scanning functions of a galvanometer-based scanner (GS), considered with an optimal profile for the user, i.e., symmetrical, linear on their active portions, and with fast stop-and-turn parts. The scope is to obtain the function that provides the highest theoretical limit of the duty cycle of the device. From the equation of the oscillatory mirror, the active torque is obtained with regard to the scanning function. Several

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