1. Articles in category: Tunable Sources

    1-24 of 382 1 2 3 4 ... 14 15 16 »
    1. Swept light source and method for controlling the same

      Swept light source and method for controlling the same

      Provided is a swept light source including one end surface coupled to a wavelength filter constituted of a diffraction grating and an end mirror via a light deflector and another end surface including a gain medium facing an output coupling mirror and which configures a laser cavity between the end mirror and the output coupling mirror, wherein a drive voltage having an AC voltage on which a DC bias voltage is superimposed is output from a control voltage source of the light deflector to an electrode pair of an electro-optic crystal, light is radiated from a light emitter to the ...

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      Mentions: NTT
    2. OptoRes presents world-record 3 MHz swept laser at SPIE BiOS / Photonics West in San Francisco

      OptoRes presents world-record 3 MHz swept laser at SPIE BiOS / Photonics West in San Francisco

      Ideally suited for optical coherence tomography, Optores‘ FDML laser with 3 MHz sweep rate is more than 10x faster than competition. Optores GmbH announces the latest upgrade to its NG-FDML series of wavelength-swept lasers. The SPIE Photonics West conference marks the launch of the new 3 MHz imaging speed option: Double as fast as previously, and more than 10x faster than any other commercially available swept laser. The new device is ideal for optical coherence tomography (OCT) in medicine, biology and industrial inspection. “Multi-MHz sweep rates are necessary for high-resolution 4D-OCT, which shows three-dimensional tissue structure live and in real ...

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    3. Ultrafast Wavenumber Linear-step-swept source Based on Synchronous Lightwave Synthesized Frequency Sweeper

      Ultrafast Wavenumber Linear-step-swept source Based on Synchronous Lightwave Synthesized Frequency Sweeper

      An ultrafast wavenumber linear-step-swept source based on a synchronous lightwave synthesized frequency sweeper (SLSFS) is demonstrated. A multi-wavelength source is used as a seed source. In SLSFS, the swept range of different wavelength components is precisely controlled by a stable programmable radio frequency (RF) signal applied on a dual-parallel Mach-Zehnder modulator (DP-MZM) instead of a conventional wavelength filter. The identical frequency shifting step of all the wavelength components promises high linear sweeping in frequency domain. The key significance of this technique is that the swept rate and the swept range increases as the number of the seed wavelengths increases. Experimentally ...

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    4. Extended Coherence Length and Depth Ranging Using a Fourier-Domain Mode-Locked Frequency Comb and Circular Interferometric Ranging

      Extended Coherence Length and Depth Ranging Using a Fourier-Domain Mode-Locked Frequency Comb and Circular Interferometric Ranging

      Fourier-domain mode locking has been a popular laser design for high-speed optical-frequency-domain imaging (OFDI), but achieving long coherence lengths, and therefore imaging range, has been challenging. The narrow linewidth of a Fourier-domain mode-locked (FDML) frequency-comb (FC) laser could provide an attractive platform for high-speed as well as long-range OFDI. Unfortunately, aliasing artifacts arising from signals beyond the principal measurement depth of the free spectral range have prohibited the use of an FDML FC laser for imaging so far. To make the increased coherence length of an FDML FC laser available, methods to manage such artifacts are required. Recently, coherent circular ...

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    5. Santec Announce a Record Wavelength Scan for an Electrically Pumped VCSEL

      Santec Announce a Record Wavelength Scan for an Electrically Pumped VCSEL

      Santec Corporation (JASDAQ: 6777) Santec, a leading manufacturer of tunable lasers, optical instruments, and fiber-optic components, announces a record 88nm wide continuous wavelength scan for an electrically pumped VCSEL (Vertical Cavity Surface Emitting Laser) light source. This performance record for a 1050nm centered VCSEL is a result of a collaborative effort between Santec, Tokyo Institute of Technology and Tokyo University’s Institute of Industrial Science. This result will be reported at the upcoming Photonics West 2019 meeting in San Francisco [1]. The High-speed Scanning Tunable VCSEL’s element is made up of two parts; the VCSEL, responsible for laser oscillation ...

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    6. Thorlabs Extends VEGA Swept Source OCT Offering

      Thorlabs Extends VEGA Swept Source OCT Offering

      Thorlabs announced today that it has added to its well‐established VEGA™ OCT line by releasing complete imaging systems, VEG210C1 and VEG220C1. Based on Thorlabs’ MEMS‐VCSEL swept‐wavelength laser source technology, these new systems are available in both 100 kHz (VEG210) and 200 kHz (VEG220) variants. Both offer the same low roll‐off and high sensitivity performance found in previous members of the VEGA OCT family. The MEMS‐VCSEL swept source and the imaging module are both packaged into a single housing including the scanning electronics and an interferometer with a balanced detector. Several key hardware controls can be ...

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    7. Dual laser frequency sweep interferometry system and method

      Dual laser frequency sweep interferometry system and method

      An optical arrangement, method and measurement system are disclosed. The arrangement includes a first input to receive a first beam from a frequency swept laser, a second input to receive a second beam from a fixed frequency pump laser source. A non-linear optical artifact receives and intermodulates the first and second beams to generate a third beam, the third being an inverted copy of the first beam mirrored relative to the fixed frequency of the pump laser source. A selective combining element outputs the first and third beams. The non-linear artifact or one or both of the lasers is selected ...

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    8. OCT swept laser with cavity length compensation

      OCT swept laser with cavity length compensation

      An optical coherence tomography system utilizes an optical swept laser that has cavity length compensator that changes an optical length of the laser cavity for different optical frequencies to increase the length of the laser cavity for lower optical frequencies. Specifically, a spectral separation between longitudinal cavity modes of the laser cavity is shortened or alternatively lengthened as a passband of a cavity tuning element sweeps through a scanband of the swept optical signal. In some examples, the compensator is implemented as two gratings. In others, it is implemented as a chirped grating device.

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    9. Long-to-short wavelength swept source

      Long-to-short wavelength swept source

      Most swept external cavity diode lasers tune in the short-to-long wavelength direction (red tuning). Lower relative intensity noise (RIN) and higher output power are typically possible in this direction. We show here that long-to-short tuning (blue tuning) is possible for a short, linear cavity laser that has both low noise and high power. This mode of operation is made possible by nonlinear frequency broadening in the semiconductor optical amplifier (SOA) followed by clipping of the red portion of the spectrum by the micro-electro-mechanical systems (MEMS) tunable Fabry-Perot filter. Blue shifting during gain recovery is an important broadening mechanism. There is ...

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    10. Voltage Noise and Jitter Analysis for Swept Source Optical Coherence Tomography using KTa1-xNbxO3 Deflector

      Voltage Noise and Jitter Analysis for Swept Source Optical Coherence Tomography using KTa1-xNbxO3 Deflector

      This paper describes voltage noise and jitter analysis for the depth deviation of a point spread function in a swept source optical coherence tomography system using a KTa1-xNbxO3 deflector. An interference waveform with voltage noise and jitter was simulated according to a previous report. Typical values for the voltage noise ΔVTYP and jitter ΔtTYPwere also obtained from a previous report and experiment. It was determined that the depth deviation is limited by the ΔtTYP of the system. Therefore, the quality of the tomographic image can be efficiently improved by reducing jitter.

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      Mentions: NTT
    11. SS-OCT enables increased speed, deeper penetration, but steeper cost

      SS-OCT enables increased speed, deeper penetration, but steeper cost

      Swept source OCT has many benefits over spectral domain OCT, but its biggest obstacle today is cost, according to Jay S. Du k er at the American Academy of Optometry annual meeting. SS-OCT is a form of fourier domain detection, which is how the echo time delay is calculated in the device, he said. The SS light source is a tunable laser that rapidly changes the wavelength, which is very expensive, he added. The reflections of depth are detected with photodetectors, not with a camera as with SD-OCT. The longer wavelength of SS-OCT images (1,000 nm to 1,300 ...

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    12. Spectrally tunable illumination system based on acousto-optic diffraction of light

      Spectrally tunable illumination system based on acousto-optic diffraction of light

      Spectrally tunable illumination is widely used for spectral imaging, spectroscopy, spectral-domain optical coherence tomography and other applications. Most of swept-wavelength light sources are based on mechanical change of narrow-band filters or on a supercontinuum laser coupled with a tunable filter. Such commercially available sources suffer either from a limited number of spectral channels or from a spatial noise caused by parasitic interferences. Here, we describe an alternative solution, which is free from the mentioned disadvantages and provides speckle-free uniform illumination. It is based on acousto-optic (AO) diffraction of a wide-band light. AO tunable filters (AOTFs) are fully software-controlled solid-state devices ...

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    13. Extended coherence length and depth ranging using a Fourier domain mode-locked frequency comb and circular interferometric ranging

      Extended coherence length and depth ranging using a Fourier domain mode-locked frequency comb and circular interferometric ranging

      Fourier domain mode-locking (FDML) has been a popular laser design for high speed optical frequency domain imaging (OFDI) but achieving long coherence lengths, and therefore imaging range, has been challenging. The narrow instantaneous linewidth of a frequency comb (FC) FDML laser could provide an attractive platform for high speed as well as long range OFDI. Unfortunately, aliasing artifacts arising from signals beyond the principle measurement depth of the free spectral range have prohibited the use of a FC FDML for imaging so far. To make the enhanced coherence length of FC FDML laser available, methods to manage such artifacts are ...

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    14. OCT system with bonded MEMS tunable mirror VCSEL swept source

      OCT system with bonded MEMS tunable mirror VCSEL swept source

      A microelectromechanical systems (MEMS)-tunable vertical-cavity surface-emitting laser (VCSEL) in which the MEMS mirror is bonded to the active region. This allows for a separate electrostatic cavity that is outside the laser's optical resonant cavity. Moreover, the use of this cavity configuration allows the MEMS mirror to be tuned by pulling the mirror away from the active region. This reduces the risk of snap down. Moreover, since the MEMS mirror is now bonded to the active region, much wider latitude is available in the technologies that are used to fabricate the MEMS mirror. This is preferably deployed as a ...

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    15. Thorlabs Releases New MEMS‐VCSEL Swept‐Wavelength Laser Sources

      Thorlabs Releases New MEMS‐VCSEL Swept‐Wavelength Laser Sources

      Thorlabs announced today that it has released next‐generation versions of its 1300 nm MEMS‐VCSEL Swept‐Wavelength Laser Sources. With a record‐breaking coherence length of over 100 mm and sweep rates of either 100 kHz or 200 kHz, the SL131090 and SL132120 are the only commercially available MEMS‐VCSEL laser sources on the market. Based on a patented microelectromechanical system (MEMS) tunable vertical cavity surface emitting laser (VCSEL), these light sources include an active power control that maintains constant output power over the lifetime of the laser. All drive electronics and trigger signals needed to seamlessly integrate these ...

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      Mentions: Thorlabs
    16. Ultra low noise Fourier domain mode locked laser for high quality megahertz optical coherence tomography

      Ultra low noise Fourier domain mode locked laser for high quality megahertz optical coherence tomography

      We investigate the origin of high frequency noise in Fourier domain mode locked (FDML) lasers and present an extremely well dispersion compensated setup which virtually eliminates intensity noise and dramatically improves coherence properties. We show optical coherence tomography (OCT) imaging at 3.2 MHz A-scan rate and demonstrate the positive impact of the described improvements on the image quality. Especially in highly scattering samples, at specular reflections and for strong signals at large depth, the noise in optical coherence tomography images is significantly reduced. We also describe a simple model that suggests a passive physical stabilizing mechanism that leads to ...

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    17. Axsun Technologies Announces Breakthrough Tunable VCSEL Platform for Optical Coherence Tomography (OCT) Imaging

      Axsun Technologies Announces Breakthrough Tunable VCSEL Platform for Optical Coherence Tomography (OCT) Imaging

      Axsun Technologies, Inc., a leading developer and supplier of MEMSbased optical engines for medical imaging, industrial spectroscopy, and optical telecommunications, today announced the development of a novel Tunable Vertical Cavity Surface Emitting Laser (Tunable VCSEL) platform for OCT imaging applications. Raising the bar on OCT imaging performance, Axsun’s new Tunable VCSEL platform leverages the company’s core strengths of high performance optical integration and cost-effective volume manufacturing. By integrating all the major tunable VCSEL components into a single compact butterfly package, the Axsun tunable VCSEL enables higher performance and flexibility, reliability and scalability with low power consumption. “While our ...

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    18. Axsun Technologies Reaches Shipment Milestone of 15,000 Swept Lasers for Optical Coherence Tomography (OCT) Imaging

      Axsun Technologies Reaches Shipment Milestone of 15,000 Swept Lasers for Optical Coherence Tomography (OCT) Imaging

      Axsun Technologies, Inc., the leading manufacturer of Swept Source Optical Coherence Tomography (SSOCT) engines, today announced that the company has shipped over 15,000 swept lasers for OCT imaging applications. “Axsun’s lasers for OCT imaging enable the highest performance systems in ophthalmology, vascular and other medical and industrial imaging applications,” explained Jonathan Hartmann, CEO of Axsun. “This significant milestone in our company’s history is a testament to Axsun’s technology leadership, the scalability of our manufacturing platform, and our incredible team. It is also an exciting milestone for our customers and the patients they serve with this leading ...

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    19. Surface emitting laser, laser array, light source device, information acquisition device, and optical coherence tomography apparatus

      Surface emitting laser, laser array, light source device, information acquisition device, and optical coherence tomography apparatus

      Provided is a surface emitting laser that is to be excited by an external light source and in which a light-emitting position is defined. A surface emitting laser includes a pair of reflecting mirrors (11, 15) and an active layer (13) that is arranged between the pair of reflecting mirrors (11, 15) and that is to be excited by light that is radiated from an external light source. A gap is formed between the active layer and one of the pair of reflecting mirrors (15), the oscillation wavelength of the surface emitting laser is changed, and a defining structure (20 ...

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    20. Spatio-temporally incremental fiber swept source

      Spatio-temporally incremental fiber swept source

      A spatio-temporally incremental fiber sweep source includes a laser light pulse generator for generating light pulses and a fiber array of individual optical fibers. The fiber array has an input end and an output end, with the fibers at the input end receiving the light pulses substantially simultaneously. The optical fibers at the output end are arranged in a raster scan pattern, e.g., a square pattern, wherein the optical delay in each fiber is greater than the previous one in the scan pattern direction. As a result light exits the array in a completely optical two dimensional raster scan ...

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    21. OCTLIGHT Closes Investment Round on Path to Commercialize OCT Swept Source

      OCTLIGHT Closes Investment Round on Path to Commercialize OCT Swept Source

      OCTLIGHT secures funding years ahead upon successful reaching key milestone OCTLIGHT ApS announces that it has closed an investment round following the successful completion of milestones towards commercializing OCT swept source modules. The funding, which was closed according to plan, will cover the activities of OCTLIGHT over the coming years, focused on development of OCT swept source modules for Ophthalmology as the primary market. Wavelength tuning range doubled to 52 nm showing path towards goal of 100 nm OCTLIGHT has achieved significant milestones towards bringing OCT swept source modules to market. The development of the core VCSEL technology continues, with ...

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    22. Apparatus and methods for one or more wavelength swept lasers and the detection of signals thereof

      Apparatus and methods for one or more wavelength swept lasers and the detection of signals thereof

      An optical instrument including at least a first and second wavelength swept vertical cavity laser (VCL) sources. The wavelength sweeping ranges spanned by the first and second VCL sources may differ with a region of spectral overlap. The first and second VCL sources may be operable under different modes of operation, wherein the modes of operation differ in at least one of: sweep repetition rate, sweep wavelength range, sweep center wavelength, and sweep trajectory. A VCL source may also exhibit sweep-to-sweep variation. Apparatus and methods are described for aligning sample signal data from the first VCL and sample signal data ...

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    23. Unfolding displacement measurement method for the aliasing interferometer signal of a wavelength-comb-swept laser

      Unfolding displacement measurement method for the aliasing interferometer signal of a wavelength-comb-swept laser

      We demonstrate an unfolding displacement measurement method to overcome the aliasing problem of wavelength-comb-swept laser (WCSL). Compared to the conventional wavelength-swept laser (WSL), the WCSL exhibits an extended coherence length, owing to the narrowing spectral linewidth of the etalon filter. However, the aliasing interference signal induces an unexpected back-bounced phenomenon during displacement measurement because of the discretely distributed comb-like periodic spectra of the etalon filter. By using the dual-reference interferometry method, the back-bounced displacement measurement can be successfully unfolded to extend the measurement range by two times. In addition, we demonstrate a longer-range surface profiling image over 18 mm within ...

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    24. Widely tunable short cavity laser

      Widely tunable short cavity laser

      A tunable source includes a short-cavity laser optimized for performance and reliability in SSOCT imaging systems, spectroscopic detection systems, and other types of detection and sensing systems. The short cavity laser has a large free spectral range cavity, fast tuning response and single transverse, longitudinal and polarization mode operation, and includes embodiments for fast and wide tuning, and optimized spectral shaping. Disclosed are both electrical and optical pumping in a MEMS-VCSEL geometry with mirror and gain regions optimized for wide tuning, high output power, and a variety of preferred wavelength ranges; and a semiconductor optical amplifier, combined with the short-cavity ...

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    1-24 of 382 1 2 3 4 ... 14 15 16 »
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