1. Articles in category: Broadband Sources

    1-24 of 192 1 2 3 4 5 6 7 8 »
    1. Optical Semiconductor Device, Driving Method Thereof, And Optical Coherence Tomography Apparatus Having The Optical Semiconductor Device

      Optical Semiconductor Device, Driving Method Thereof, And Optical Coherence Tomography Apparatus Having The Optical Semiconductor Device

      The present invention provides an optical semiconductor device which can make a wavelength band of emitted light wider than that of a conventional optical semiconductor device. The optical semiconductor device includes: an active layer including a multiple quantum well structure; and at least one electrode pair for injecting an electric current into the active layer, wherein the multiple quantum well structure has a first quantum well and a second quantum well which is different from the first quantum well, and the first quantum well and the second quantum well are mutually different in at least two out of a composition ...

      Read Full Article
    2. Light Source And Optical Coherence Tomography Apparatus Including The Light Source

      Light Source And Optical Coherence Tomography Apparatus Including The Light Source

      A light source includes an upper electrode layer, a lower electrode layer, and an active layer interposed therebetween. At least one of the upper and lower electrode layers is divided into a plurality of electrodes separated from each other in an in-plane direction of the active layer. The separated electrodes independently inject current into a plurality of different regions in the active layer. The light source emits light by injecting current from the upper and lower electrode layers into the active layer, guide the light in the in-plane direction, and output the light. The plurality of different regions in the ...

      Read Full Article
    3. Filtered ASE swept source for OCT medical imaging

      Filtered ASE swept source for OCT medical imaging

      An integrated swept wavelength optical source uses a filtered ASE signal with an optical amplifier and tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a first tunable Fabry Perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal, and a second tunable Fabry Perot filter, installed on the bench, for spectrally filtering the amplified tunable signal from the amplifier. A self-tracking arrangement is also possible where a single tunable filter ...

      Read Full Article
    4. Development of a high power supercontinuum source in the 1.7 μm wavelength region for highly penetrative ultrahigh-resolution optical coherence tomography

      Development of a high power supercontinuum source in the 1.7 μm wavelength region for highly penetrative ultrahigh-resolution optical coherence tomography

      We developed a high power supercontinuum source at a center wavelength of 1.7 μm to demonstrate highly penetrative ultrahigh-resolution optical coherence tomography (UHR-OCT). A single-wall carbon nanotube dispersed in polyimide film was used as a transparent saturable absorber in the cavity configuration and a high-repetition-rate ultrashort-pulse fiber laser was realized. The developed SC source had an output power of 60 mW, a bandwidth of 242 nm full-width at half maximum, and a repetition rate of 110 MHz. The average power and repetition rate were approximately twice as large as those of our previous SC source [ 20 ]. Using the developed ...

      Read Full Article
    5. III-V Quantum Dot Lasers Grown Directly on Silicon

      III-V Quantum Dot Lasers Grown Directly on Silicon

      The University of California Santa Barbara (UCSB) has grown 1.3 μm-wavelength indium arsenide (InAs) quantum dot (QD) lasers directly on silicon, with record device performance. The breakthrough approach promises an alternative to wafer bonding lasers grown on native substrates, which, in return, could help advance silicon photonics by way of cheap large-scale growth and high-performing QD optoelectronics. The new QD lasers consist of billions of nanometer-sized indium arsenide (InAs) quantum dots, cladded on either side by gallium-arsenide-(GaAs)-related compounds. The structure is grown using a technique called molecular beam epitaxy (MBE) on germanium/silicon substrates. “The excitement from ...

      Read Full Article
    6. NKT Photonics releases World’s most affordable supercontinuum laser

      NKT Photonics releases World’s most affordable  supercontinuum laser

      NKT Photonics, the leading manufacturer of supercontinuum sources, releases new SuperK COMPACT – the World’s most affordable supercontinuum fiber laser. The new source provides single mode, fiber delivered light in the entire 450-2400nm range and, unlike most supercontinuum sources on the market, the laser can be triggered externally and synced with low jitter from single shot up to 20 kHz. The previous generation COMPACT can be found in laboratories around the World where it is the daily driver within applications like component characterization, test & measurement and spectroscopy, or simply as a general purpose laboratory white light source. However, the low ...

      Read Full Article
      Mentions: NKT Photonics
    7. Ultrahigh-Resolution Optical Coherence Tomography with LED-Phosphor-Based Broadband Light Source

      Ultrahigh-Resolution Optical Coherence Tomography with LED-Phosphor-Based Broadband Light Source

      This study proposed and demonstrated the potential use of LED phosphors as a simple light source for ultrahigh-resolution spectral-domain optical coherence tomography (SD-OCT) in the visible regime. Excited by a 405 nm diode laser, broadband spontaneous emission from three different LED phosphors was generated. The best axial resolution was 1.7 µm in air, and finally, corresponding three-dimensional (3D) ultrahigh-resolution SD-OCT imaging was performed with the proposed broadband light source.

      Read Full Article
    8. Novel waveguide increases superluminescent output

      Novel waveguide increases superluminescent output

      A partnershipbetween Polish and Japanese researchers claims to have set a new benchmark for the combination of output power and smoothness of spectral output for GaN superluminescent diodes. This team’s emitter features a ‘J-shaped’ waveguide and could be used in fibre-optic gyroscopes and optical coherence tomography. Both applications require a light source that combines a high degree of spatial coherence with low time coherence. These conditions are met with the superluminescent diodes. They were developed in the arsenide material system in the 1970s, but the shorter wavelengths emitted by GaN-based materials are beneficial.

      Read Full Article
    9. Laser plus phosphor emits white light without

      Laser plus phosphor emits white light without

      Combining a blue-emitting indium gallium nitride (InGaN) LED with a yellow YAG phosphor has produced one of most successful commercial photonic devices ever—the white-light LED. But there is a problem: InGaN LEDs suffer from efficiency droop, in which their efficiency at high currents, and therefore high optical outputs, is lower than that for low currents and optical outputs. However, other InGaN light sources—blue- and near-UV-emitting laser diodes—do not suffer from this problem. With this in mind, researchers at the University of California, Santa Barbara (UCSB), led by material scientists Kristin Denault and Michael Cantore, have combined laser ...

      Read Full Article
    10. High-Optical-Power InGaN Superluminescent Diodes with “j-shape” Waveguide

      High-Optical-Power InGaN Superluminescent Diodes with “j-shape” Waveguide

      We demonstrate blue-violet InGaN superluminescent diodes (SLDs) with bent-waveguide (j-shape) geometry, emitting optical power exceeding 200 mW for SLD with 1-mm-long waveguide. The adopted j-shape geometry prevents devices from lasing, even at the highest applied currents (450 mA). However, high-resolution measurements reveal the appearance of spectral ripples at currents on the order of 250 mA. The maximum output power increases with the waveguide length

      Read Full Article
    11. Coherent Launches Turnkey 550 mW, Sub-10 fs Laser

      Coherent Launches Turnkey 550 mW, Sub-10 fs Laser

      The latest member of the Vitara family ofextreme performance, closed-box, ultrafast oscillators from Coherent, Inc. (Santa Clara, CA) – the Vitara UBB –provides hands-free access to pulsewidths under 10 femtoseconds, with options below 8 fs on request. Vitara UBB (Ultra BroadBand) achieves its short transform-limited pulsewidths because of its very broad bandwidth (> 200 nm at the -10 dB point). Its unique combination of short pulsewidths, broad bandwidth, high reliability and ease-of-use make Vitara UBB the ideal laser for applications in terahertz pulse generation, optical coherence tomography (OCT), pump-probe spectroscopy, multiplexed CARS spectroscopy, non-linear microscopic imaging and seeding short-pulse amplifiers. By integrating ...

      Read Full Article
    12. Broadband wavelength swept source combining a quantum dot and a quantum well SOA in the wavelength range of 1153–1366 nm

      Broadband wavelength swept source combining a quantum dot and a quantum well SOA in the wavelength range of 1153–1366 nm

      wide tuning range wavelength swept laser for high axial resolution optical coherence tomography reported. Here, a parallel configuration of a quantum dot semiconductor optical amplifier (SOA) and a quantum well SOA is utilised for broadband optical source. The total scanning range of over 210 nm (192 nm at 10 dB) from 1153 to 1366 nm is reported. To investigate the feasiblity of the swept light source, demonstrated is an optical frequency domain imaging (OFDI) system. The system sensitivity of 101 dB is reported and axial resolution of 6.0 µm in air is achieved. Finally, ex vivo OFDI imaging of ...

      Read Full Article
      Mentions: Samsung
    13. Broadband superluminescent diodes with bell-shaped spectra emitting in the range from 800 to 900 nm

      Broadband superluminescent diodes with bell-shaped spectra emitting in the range from 800 to 900 nm

      Quantum-well superluminescent diodes (SLD) with extremely thin active (AlGa)As and (InGa)As layers and centre wavelengths about 810, 840, 860 and 880 nm are experimentally studied. Their emission spectrum possesses the shape close to Gaussian, its FWHM being 30 – 60 nm depending on the length of the active channel and the level of pumping. Under cw injection, the output power of light-emitting modules based on such SLDs can amount to 1.0 – 25 mW at the output of a single-mode fibre. It is demonstrated that the operation lifetime of these devices exceeds 30000 hours. Based on the light-emitting modules ...

      Read Full Article
      Mentions: Superlum
    14. Generation of a low divergent supercontinuum for mid-IR high power delivery through a large mode area photonic bandgap fiber

      Generation of a low divergent supercontinuum for mid-IR high power delivery through a large mode area photonic bandgap fiber

      We numerically report the feasibility of generating broadband low divergent supercontinuum covering the entire wavelength window of 1.5–3.5 μm from a 2.25 m long effectively single mode all solid, soft glass based, photonic bandgap fiber with mode area as large as 1100 μm 2 . Owing to its chosen fabrication, friendly geometry, and the chosen material composition, the proposed fiber-based light source should be useful as a mid-wave IR pulsed broadband light source for applications such as high power delivery, optical coherence tomography and mid-IR spectroscopy.

      Read Full Article
    15. Monolithically grown multi-color InAs quantum dots as a spectral-shape-controllable near-infrared broadband light source

      Monolithically grown multi-color InAs quantum dots as a spectral-shape-controllable near-infrared broadband light source

      We have grown monolithic multi-color InAs quantum dots (QDs) for use as a near-infrared (NIR) broadband light source. Our previously developed rotational metal mask enables selective-area growth of QD ensembles with emission peak wavelengths controlled by strain-reducing layers thicknesses, varying the emission approximately 1.2–1.3  μ m. The peak shift value was up to 120 nm, and a combined 160-nm-bandwidth emission spectrum was achieved. Further, the emission spectra shapes were controlled using specific optical excitation powers for each QD ensemble. These results demonstrate the effectiveness of multi-color QDs as a spectrum-shape-controllable NIR broadband light source, particularly suited for optical ...

      Read Full Article
    16. Mirau-based full-field time-domain optical coherence tomography using Ce3+ :YAG crystal fiber light source

      Mirau-based full-field time-domain optical coherence tomography using Ce3+ :YAG crystal fiber light source

      Based on single-objective construction utilizing high brightness Ce 3+ :YAG single-clad crystal fiber light source, this Mirau-based full-field time-domain optical coherence tomography with circular polarization incident light represents deeper penetration in scattering medium. Using objective-changeable ability of home-designed Mirau objective, this system provides different applications, like biological tissue and single cells, by different spatial resolution with corresponding dynamics. High quality image relying on less ghost image and near common-path interference was demonstrated under this compact and power-stable system.

      Read Full Article
    17. Coherence Properties of Supercontinuum Generated in Dispersion-Tailored Lead-Silicate Microstructured Fiber Taper

      Coherence Properties of Supercontinuum Generated in Dispersion-Tailored Lead-Silicate Microstructured Fiber Taper

      This article details the numerically studied coherence properties of the supercontinuum generated in a lead-silicate microstructured fiber taper, with an increasing core radius along the propagation distance that tailors the dispersion property. Simulations are conducted by adding quantum noise into the input pulse at 1.55 μm, and the complex degree of first-order coherence function and the overall spectral coherence degree are both calculated. Although the spectral broadening is comparable, the coherence degree is shown to vary with different pumping conditions. It decreases with higher peak power and longer duration due to the significant competition between the soliton-fission process and ...

      Read Full Article
    18. Multifunctional Laser Device

      Multifunctional Laser Device

      A multifunctional laser device configured to be applicable as such in each of: multiple photon processes, nano structuring processes, optical coherence tomography, Terahertz (THZ) spectroscopy, THz imaging; or a combination of such processes; and comprising a mode-locked linear (X or Z-folded) fs laser resonator having a repetition rate of at least 300 MHz and 600 MHz at most and, thus, a corresponding short resonator length, said fs laser resonator further being a dispersive mirrors cavity having an average negative GDD (Group Delay Dispersion) in the spectral range of the laser operation, and being arranged to generate laser pulses with a ...

      Read Full Article
      Mentions: Femtolasers Tuan Le
    19. MODE-LOCKED Laser Light Source Device And Optical Coherence Tomography Apparatus Using Same

      MODE-LOCKED Laser Light Source Device And Optical Coherence Tomography Apparatus Using Same

      Provided is a mode-locked laser light source device capable of implementing laser light with a narrow oscillation spectral distribution. This mode-locked laser light source device comprises: a semiconductor optical amplifier (1) wherein carriers are generated by the injection of an injection current (I) thereinto, a pulse of laser light (P) is amplified by the consumption of the carriers, and phase modulation equivalent to self-phase modulation depending on the pulse intensity of the laser light (P) occurs due to a change in the density of carriers; a sweep modulation unit (3) which makes the oscillation wavelength of the pulse of the ...

      Read Full Article
    20. Feature Of The Week 4/7/2013: Seoul National University Presentation on Fiber Laser Technology For Broadband Light Generation

      Feature Of The Week 4/7/2013: Seoul National University Presentation on Fiber Laser Technology For Broadband Light Generation

      Over the past decade fiber laser technology has made dramatic advances in a multitude of regimes. Such advances, firstly initiated with the development of continuous-wave fiber lasers of high average power, including ytterbium (Yb)-doped fiber lasers at ~1.1 um, erbium (Er)-doped fiber lasers at ~1.6 um, and thulium (Tm)-doped fiber at ~2 um, have made another great progress in fiber-based pulsed sources of high peak power. In particular, such fiber-based pulsed sources are very useful for nonlinear wavelength conversion, so that the continuum generation combined with fiber-based pulsed sources has become a vivid research area ...

      Read Full Article
    21. Adaptive broadband continuum source at 1200–1400 nm based on an all-fiber dual-wavelength master-oscillator power amplifier and a high-birefringence fiber

      Adaptive broadband continuum source at 1200–1400 nm based on an all-fiber dual-wavelength master-oscillator power amplifier and a high-birefringence fiber

      We experimentally analyze the stimulated Raman scattering characteristics of a high-birefringence fiber (HBF), which presents an extraordinary level of spectral broadening incurred by the strong nonlinear interaction between the pump and Stokes pulses via the polarization-mode dispersion and group-velocity dispersion of the fiber. We also investigate the impact of the inter-pulse time-delay on the additional spectra broadening when dual-wavelength pump pulses are used. Exploiting these unique SRS properties of the HBF, we develop a novel Raman continuum source based on an all-fiber dual-wavelength master-oscillator power amplifier that can generate a dip-free spectrum in the 1200−1400-nm spectral range. We finally ...

      Read Full Article
    22. A new small-package super-continuum light source for optical coherence tomography

      A new small-package super-continuum light source for optical coherence tomography

      Broadband light sources provide a significant benefit for optical coherence tomography (OCT) imaging concerning the axial resolution. Light sources with bandwidths over 200 nm result in an axial resolution up to 2 microns. Such broad band OCT imaging can be achieved utilizing super continuum (SC) light sources. The main important disadvantage of commercial SC light sources is the overall size and the high costs. Therefore, the use of SC light sources in small OCT setups and applications is limited. We present a new small housing and costeffective light source, which is suitable for OCT imaging. The used light source has ...

      Read Full Article
    23. Supercontinuum sources make their presence felt

      Supercontinuum sources make their presence felt

      Market for the ultra-broadband sources and related technology estimated at $50 million, with microscopy a key application. After transitioning from a laboratory curiosity to a genuine commercial tool in recent years, supercontinuum sources have emerged to create a fledgling marketplace. The point was one of several made by Wilhelm Kaenders, co-founder and co-president of Toptica Photonics, at the Lasers & Photonics Marketplace Seminar in San Francisco last week. “This new light source is finding applications in fields ranging from optical coherence tomography (OCT), frequency metrology, and fluorescence lifetime imaging microscopy (FLIM), to optical communications and gas sensing,” he told the conference ...

      Read Full Article
    24. Dispersion-flattened supercontinuum light source design at center wavelength for high resolution optical coherence tomography in ophthalmology

      Dispersion-flattened supercontinuum light source design at center wavelength for high resolution optical coherence tomography in ophthalmology

      Optimal wavelength light sources are designed for medical imaging to overcome the effects of the dispersion of the sampling medium of biological tissues which contain about 60% water in normal tissues and 90% water in anatomic structures such as in the eye. Based on highly nonlinear photonic crystal fiber (HNL-PCF), two light sources are designed at center wavelength as the influences of the dispersion of the main component of biological tissues on the resolution of optical coherence tomography (OCT) can be eliminated. Using finite element method with a circular perfectly matched boundary layer, it is shown through simulations that the ...

      Read Full Article
    1-24 of 192 1 2 3 4 5 6 7 8 »
  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, Velocimetry
    4. Miscellaneous:

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

  3. OCT Companies in the News

    1. (2 articles) Canon Medical Systems