1. Articles in category: Broadband Sources

    1-24 of 237 1 2 3 4 5 6 7 8 9 10 »
    1. Wideband ultrafast fiber laser sources for OCT and metrology

      Wideband ultrafast fiber laser sources for OCT and metrology

      Fiber lasers, which use optical fibers as ideal waveguides, have been attracting a great deal of attention as stable, practical, and maintenance-free lasers. Using a combination of an ultrashort-pulse fiber laser and a nonlinear fiber, we can realize wideband highly functional ultrafast fiber laser sources. The generation of ultrashort pulses with wide wavelength tunability and supercontinua based on fiber lasers and nonlinear fibers has been demonstrated. These techniques are useful for laser applications, especially for imaging and metrology. In this topical review, the fundamentals of and recent progress in wideband ultrafast fiber laser sources and their applications are reviewed mainly ...

      Read Full Article
    2. 15 Open PhD Positions within Supercontinuum Light Sources and Applications at Technical University of Denmark

      15 Open PhD Positions within Supercontinuum Light Sources and Applications at Technical University of Denmark

      We are seeking 15 skilled candidates for PhD positions across Europe in supercontinuum light sources and applications. The candidates should have a background in physics and interest in nonlinear optics, fibre optics and waveguides, and laser physics. SUPUVIR ( SUPercontinuum broadband light sources covering UV to IR applications ) is a new Innovative Training Network (ITN) funded by the European H2020 programme. SUPUVIR will focus on so-called supercontinuum laser sources, which essentially are laser sources emitting coherent laser light that is broadband enough to be considered white. The PhD students will be given extensive knowledge in silica and soft-glass chemistry, preform design ...

      Read Full Article
    3. Method and apparatus for producing supercontinuum light for medical and biological applications

      Method and apparatus for producing supercontinuum light for medical and biological applications

      A method and an apparatus are provided for producing SuperContinuum (SC) light for medical and biological applications is provided. Pulses are focused from a laser system into at least one of a pressurized cell and one or more fibers. A pump pulse is converted into the SC light at a specified rate of repetition. The SC light is applied at the specified rate of repetition to tissue for medical and biological applications.

      Read Full Article
      Mentions: Robert R. Alfano
    4. Single all-fiber-based nanosecond-pulsed supercontinuum source for multispectral photoacoustic microscopy and optical coherence tomography

      Single all-fiber-based nanosecond-pulsed supercontinuum source for multispectral photoacoustic microscopy and optical coherence tomography

      We report the usefulness of a single all-fiber-based supercontinuum (SC) source for combined photoacoustic microscopy (PAM) and optical coherence tomography (OCT). The SC light is generated by a tapered photonic crystal fiber pumped by a nanosecond pulsed master oscillator power amplifier at 1064 nm. The spectrum is split into a shorter wavelength band (500–800 nm) for single/multi-spectral PAM and a longer wavelength band (800–900 nm) band for OCT. In vivo mouse ear imaging was achieved with an integrated dual-modality system. We further demonstrated its potential for spectroscopic photoacoustic imaging by doing multispectral measurements on retinal pigment epithelium ...

      Read Full Article
    5. Simulation of broad spectral bandwidth emitters at 1060 nm for retinal optical coherence tomography

      Simulation of broad spectral bandwidth emitters at 1060 nm for retinal optical coherence tomography

      The simulation of broad spectral bandwidth light sources (semiconductor optical amplifiers (SOA) and superluminescent diodes (SLD)) for application in ophthalmic optical coherence tomography is reported. The device requirements and origin of key device parameters are outlined, and a range of single and double InGaAs/GaAs quantum well (QW) active elements are simulated with a view to application in different OCT embodiments. We confirm that utilising higher order optical transitions is beneficial for single QW SOAs, but may introduce deleterious spectral modulation in SLDs. We show how an addition QW may be introduced to eliminate this spectral modulation, but that this ...

      Read Full Article
    6. Superluminescent diode with a broadband gain based on self-assembled InAs quantum dots and segmented contacts for an optical coherence tomography light source

      Superluminescent diode with a broadband gain based on self-assembled InAs quantum dots and segmented contacts for an optical coherence tomography light source

      We report a broadband-gain superluminescent diode (SLD) based on self-assembled InAs quantum dots (QDs) for application in a high-resolution optical coherence tomography (OCT) light source. Four InAs QD layers, with sequentially shifted emission wavelengths achieved by varying the thickness of the In 0.2 Ga 0.8 As strain-reducing capping layers, were embedded in a conventional p-n heterojunction comprising GaAs and AlGaAs layers. A ridge-type waveguide with segmented contacts was formed on the grown wafer, and an as-cleaved 4-mm-long chip (QD-SLD) was prepared. The segmented contacts were effective in applying a high injection current density to the QDs and obtaining ...

      Read Full Article
    7. High-power supercontinuum generation using high-repetition-rate ultrashort-pulse fiber laser for ultrahigh-resolution optical coherence tomography in 1600 nm spectral band

      High-power supercontinuum generation using high-repetition-rate ultrashort-pulse fiber laser for ultrahigh-resolution optical coherence tomography in 1600 nm spectral band

      We describe the generation of a high-power, spectrally smooth supercontinuum (SC) in the 1600 nm spectral band for ultrahigh-resolution optical coherence tomography (UHR-OCT). A clean SC was achieved by using a highly nonlinear fiber with normal dispersion properties and a high-quality pedestal-free pulse obtained from a passively mode-locked erbium-doped fiber laser operating at 182 MHz. The center wavelength and spectral width were 1578 and 172 nm, respectively. The output power of the SC was 51 mW. Using the developed SC source, we demonstrated UHR-OCT imaging of biological samples with a sensitivity of 109 dB and an axial resolution of 4 ...

      Read Full Article
    8. Optimal operational conditions for supercontinuum-based ultrahigh-resolution endoscopic OCT imaging

      Optimal operational conditions for supercontinuum-based ultrahigh-resolution endoscopic OCT imaging

      We investigated the optimal operational conditions for utilizing a broadband supercontinuum (SC) source in a portable 800 nm spectral-domain (SD) endoscopic OCT system to enable high resolution, high-sensitivity, and high-speed imaging in vivo . A SC source with a 3-dB bandwidth of ∼ 246     nm was employed to obtain an axial resolution of ∼ 2.7     μm (in air) and an optimal detection sensitivity of ∼ − 107     dB with an imaging speed up to 35 frames/s (at 70 k A-scans/s). The performance of the SC-based SD-OCT endoscopy system was demonstrated by imaging guinea pig esophagus in vivo , achieving image quality comparable to ...

      Read Full Article
    9. Highly functional ultrashort pulse fiber laser sources and applications for optical coherence tomography

      Highly functional ultrashort pulse fiber laser sources and applications for optical coherence tomography

      We have been investigating highly functional ultrashort pulse fiber laser sources for highly sensitive, ultrahigh resolution optical coherence tomography (UHR-OCT). The coherent, low-noise, and Gaussian like wideband super-continuum (SC) sources were developed at five different wavelength regions between 0.8 and 1.7 um in order to investigate the wavelength dependence of OCT imaging. A real-time imaging was achieved with spectral domain OCT system. A fiber laser based, rapid, widely wavelength tunable narrow linewidth source was also developed. The UHR-OCT imaging of biological samples were demonstrated using the developed OCT systems.

      Read Full Article
    10. Leica Microsystems and NKT Photonics sign supercontinuum laser supply contract

      Leica Microsystems and NKT Photonics sign supercontinuum laser supply contract

      Leica Microsystems signed a 14-month supply contract with NKT Photonics to deliver significant numbers of its market-leading SuperK EXTREME supercontinuum lasers. The SuperK EXTREME powers the Leica TCS SP8 X high-end confocal microscope used globally for high-resolution bio imaging. NKT Photonics CTO, Christian Poulsen on the collaboration with Leica Microsystems: “We have worked with Leica Microsystems since 2005 and their World-renowned dedication to quality and performance has been a great benchmark for us in our product development. Today, we are proud to deliver the best supercontinuum lasers in the industry - lasers worthy of the iconic Leica logo.” CEO Basil Garabet ...

      Read Full Article
      Mentions: NKT Photonics Leica
    11. The Fabrication and Characterization Study of Broadband and High Resolution of Ce/Cr-Doped Crystal Fiber for Optical Coherence Tomography Light Sources (Thesis)

      The Fabrication and Characterization Study of Broadband and High Resolution of Ce/Cr-Doped Crystal Fiber for Optical Coherence Tomography Light Sources (Thesis)

      We report the fabrication and characteristics of Ce-doped fibers (CeDFs) and Cr-doped fibers (CDFs) based on drawing tower technique. The CeDFs show an emission from 480 to 650 nm, 600 to 800 nm, and 700 to 950 nm with a power density of 21.1 nW/nm, 79.1 nW/nm and 63.8 nW/nm, respectively. The CDFs exhibit an emission from 975 to 1300 nm with a power density of 27.3 nW/nm which was dominated by Cr4+ near-Gaussian ASE spectrum. For fiber-based OCT system, the measured broadband emission of CeDFs and CDFs showed four different high ...

      Read Full Article
    12. Superluminescent diode and optical coherence tomography apparatus including the superluminescent diode

      Superluminescent diode and optical coherence tomography apparatus including the superluminescent diode

      A superluminescent diode which amplifies light through stimulated amplification and outputs emitted beams from one of edges at two ends includes a cladding layer of a first conductivity type formed on a semiconductor substrate, an active layer formed on the cladding layer of the first conductivity type, a cladding layer of a second conductivity type formed on the active layer, and a multilayer film formed at the other edge opposite to the one edge that emits the beams, reflectance of which has wavelength dependence, and a spectral shape of the emitted beams output from the one edge is controllable by ...

      Read Full Article
    13. GaAs-Based Superluminescent Light-Emitting Diodes with 290-nm Emission Bandwidth by Using Hybrid Quantum Well/Quantum Dot Structures

      GaAs-Based Superluminescent Light-Emitting Diodes with 290-nm Emission Bandwidth by Using Hybrid Quantum Well/Quantum Dot Structures

      A high-performance superluminescent light-emitting diode (SLD) based upon a hybrid quantum well (QW)/quantum dot (QD) active element is reported and is assessed with regard to the resolution obtainable in an optical coherence tomography system. We report on the appearance of strong emission from higher order optical transition from the QW in a hybrid QW/QD structure. This additional emission broadening method contributes significantly to obtaining a 3-dB linewidth of 290 nm centered at 1200 nm, with 2.4 mW at room temperature.

      Read Full Article
    14. Small, inexpensive, and incredibly resilient: A new femtosecond laser for industry

      Small, inexpensive, and incredibly resilient: A new femtosecond laser for industry

      A team at the University of Warsaw, Faculty of Physics has created a laser capable of generating ultrashort pulses of light even under extremely difficult external conditions. This unique combination of precision and resilience is due to the fact that the whole process of generating femtosecond laser pulses takes place within a specially-selected optical fiber. Its appearance seems quite inconspicuous: just a flat, rectangular box, tens of centimeters across and about the same height, with a thin, shiny-tipped "thread" leading out of it, so long that it is rolled up into a coil. This small instrument, built by physicists from ...

      Read Full Article
    15. High-speed ultrahigh-resolution spectral domain optical coherence tomography using high-powersupercontinuum at 0.8 µm wavelength

      High-speed ultrahigh-resolution spectral domain optical coherence tomography using high-powersupercontinuum at 0.8 µm wavelength

      We demonstrated high-speed ultrahigh-resolution (UHR) optical coherence tomography (OCT) in the 800 nm wavelength region. A high-power coherent supercontinuum (SC) and a high-speed line scan camera were used to construct a spectral domain OCT. The axial resolution was 3.1 µm in air and 2.3 µm in tissue. The dependence of sensitivity on the SC power and A-scan rate was examined. For the A-scan rate of 70 kHz, the sensitivity of 104 dB was achieved for the SC power higher than 60 mW. High-speed in vivo UHR-OCT imaging was demonstrated for zebrafish embryo and swimming medaka.

      Read Full Article
    16. Broadband infrared light emitting device

      Broadband infrared light emitting device

      There is provided a broadband infrared light emitting device that radiates infrared light having a band broader than a conventional broadband infrared light emitting device. [MEANS FOR SOLVING] The broadband infrared light emitting device at least includes: a light source 4 that emits first excitation light .lamda.1 in a first wavelength range; a first glass phosphor 51 that has an excitation band in a first wavelength range, and when the first excitation light .lamda.1 is incident thereon, emits second excitation light .lamda.2 in a second wavelength range and first infrared light .lamda.3 in a third wavelength ...

      Read Full Article
    17. Broadband supercontinuum generation using a hollow optical fiber filled with copper-ion-modified DNA

      Broadband supercontinuum generation using a hollow optical fiber filled with copper-ion-modified DNA

      We experimentally demonstrated supercontinuum generation through a hollow core photonic bandgap fiber (HC-PBGF) filled with DNA nanocrystals modified by copper ions in a solution. Both double-crossover nano DNA structure and copper-ion-modified structure provided a sufficiently high optical nonlinearity within a short length of hollow optical fiber. Adding a higher concentration of copper ion into the DNA nanocrystals, the bandwidth of supercontinuum output was monotonically increased. Finally, we achieved the bandwidth expansion of about 1000 nm to be sufficient for broadband multi-spectrum applications.

      Read Full Article
    18. Optical characterization of In-flushed InAs/GaAs quantum dots emitting a broadband spectrum with multiple peaks at ~1 μm

      Optical characterization of In-flushed InAs/GaAs quantum dots emitting a broadband spectrum with multiple peaks at ~1 μm

      We investigated optical properties of In-flushed InAs quantum dots (QDs) grown on a GaAs substrate by molecular beam epitaxy. By using the In-flush technique for setting the height of self-assembled InAs QDs, we have tuned the emission wavelength of InAs QDs to the ~1 μm regime, which can be utilized as a non-invasive and deeply penetrative probe for biological and medical imaging systems. The controlled emission exhibited a broadband spectrum comprising multiple peaks with an interval of approximately 30 meV. We examined the origin of the multiple peaks using spectral and time-resolved photoluminescence, and concluded that it is attributed to ...

      Read Full Article
    19. Mid-infrared photonics: Spiral superluminescent emitter

      Mid-infrared photonics: Spiral superluminescent emitter

      Superluminescent (SL) light sources, which offer the beneficial combination of a broad emission bandwidth with low temporal and high spatial coherence, have many potential industrial and medical applications. In particular, mid-infrared (MIR) SL light sources that are suitable for use in an optical coherence tomography system would be attractive for…

      Read Full Article
    20. Imaging of spectral-domain optical coherence tomography using a superluminescent diode based on InAs quantum dots emitting broadband spectrum with Gaussian-like shape

      Imaging of spectral-domain optical coherence tomography using a superluminescent diode based on InAs quantum dots emitting broadband spectrum with Gaussian-like shape

      We developed a low-coherence light source based on self-assembled InAs quantum dots (QDs) with controlled emission wavelengths and applied it to optical coherence tomography (OCT) imaging. A current-driven superluminescent diode (SLD) light source including four layers of QDs exhibits a broadband (80-nm-bandwidth) emission centered at approximately 1.2 µm with a Gaussian-like spectral shape at room temperature. Spectral-domain OCT (SD-OCT) using the QD-SLD as a light source was developed and imaging with the SD-OCT was demonstrated. The axial resolution was estimated to be approximately 8 µm in air and no apparent side lobes appeared beside the point spread function, indicating ...

      Read Full Article
    21. Broadband generation of mid IR, coherent continua with optical fibers

      Broadband generation of mid IR, coherent continua with optical fibers

      Coherent and compact supercontinuum light sources for the mid IR spectral regime are disclosed and exemplary applications thereof. The supercontinuum generation is based on the use of highly nonlinear fibers or waveguides. In at least one embodiment the coherence of the supercontinuum sources is increased using low noise mode locked short pulse sources. Compact supercontinuum light sources can be constructed with the use of passively mode locked fiber or diode lasers. Wavelength tunable sources can be constructed using appropriate optical filters or frequency conversion sections. Highly coherent supercontinuum sources further facilitate coherent detection schemes and can improve the signal/noise ...

      Read Full Article
    22. Frequency combs in molecular fingerprint region

      Frequency combs in molecular fingerprint region

      Silicon nanowire optical waveguides dramatically broaden mid-infrared frequency comb spectra, scientists report. Frequency combs are commercially available in the visible and near-infrared spectral ranges. The mid-infrared spectral region (2-20?m), however, is still emerging. Many applications in spectroscopy, material science, security and industry process control, or chemical, biological and medical sensing would straightforwardly take advantage of mid-infrared photonics devices of higher performance.

      Read Full Article
    23. High resolution Fourier domain optical coherence tomography in the 2 um wavelength range using a broadband supercontinuum source

      High resolution Fourier domain optical coherence tomography in the 2 um wavelength range using a broadband supercontinuum source

      A 220 nm bandwidth supercontinuum source in the two-micron wavelength range has been developed for use in a Fourier domain optical coherence tomography (FDOCT) system. This long wavelength source serves to enhance probing depth in highly scattering material with low water content. We present results confirming improved penetration depth in high opacity paint samples while achieving the high axial resolution needed to resolve individual paint layers. This is the first FDOCT developed in the 2 μm wavelength regime that allows fast, efficient capturing of 3D image cubes at a high axial resolution of 13 μm in air (or 9 μm ...

      Read Full Article
    24. Supercontinuum generation for ultrahigh-resolution optical coherence tomography at wavelength of 0.8µm using carbon nanotube fiber laser and similariton amplifier

      Supercontinuum generation for ultrahigh-resolution optical coherence tomography at wavelength of 0.8µm using carbon nanotube fiber laser and similariton amplifier

      We demonstrated supercontinuum (SC) generation for ultrahigh-resolution optical coherence tomography (UHR-OCT) in the 0.8 µm wavelength region using an ultrashort-pulse fiber laser system. An Er-doped ultrashort-pulse fiber laser with single-wall carbon nanotubes was developed as the seed pulse source. A 46 fs, highest quality, pedestal-free, clean, ultrashort pulse was generated with a similariton amplifier. Then, a 60 fs ideal ultrashort pulse was generated at a wavelength of 0.8 µm with a second-harmonic generation (SHG) crystal, and a Gaussian-like SC was generated in a photonic crystal fiber. UHR-OCT was demonstrated using the generated SC, and precise images of a ...

      Read Full Article
    1-24 of 237 1 2 3 4 5 6 7 8 9 10 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Popular Articles

  3. Organizations in the News

    1. (1 articles) Nagoya University
  4. People in the News

    1. (1 articles) Norihiko Nishizawa