1. Articles in category: Probes

    1-24 of 469 1 2 3 4 ... 18 19 20 »
    1. Endoscopic micro-optical coherence tomography with extended depth of focus using a binary phase spatial filter

      Endoscopic micro-optical coherence tomography with extended depth of focus using a binary phase spatial filter

      Micro-optical coherence tomography (μOCT) is an advanced imaging technique that acquires a three-dimensional microstructure of biological samples with a high spatial resolution, up to 1 μm, by using a broadband light source and a high numerical aperture (NA) lens. As high NA produces a short depth of focus (DOF), extending the DOF is necessary to obtain a reasonable imaging depth. However, due to the complexity of optics and the limited space, it has been challenging to fabricate endoscopic μOCT, which is essential for clinical translation. Here, we report an endoscopic μOCT probe with an extended DOF by using a binary ...

      Read Full Article
    2. Low-cost hand-held probe for depth-resolved low-coherence interferometry

      Low-cost hand-held probe for depth-resolved low-coherence interferometry

      We report on the development of a low-cost hand-held low-coherence interferometric imaging system based on the principle of linear optical coherence tomography (Linear OCT), a technique which was first proposed in the early 2000s as a simpler alternative to the conventional time-domain and Fourier-domain OCT. A bench-top implementation of the proposed technique is first presented and validated. The axial resolution, SNR, and sensitivity roll-of of the system was estimated to be 5.2 μm and 80 dB, and 3.7 dB over a depth of 0.15 mm, respectively. After validating the bench-top system, two hand-held probe implementations for contact-based ...

      Read Full Article
    3. Miniature Endoscope for Multimodal Imaging

      Miniature Endoscope for Multimodal Imaging

      A single miniature endoscope capable of concurrently probing multiple contrast mechanisms of tissue in high resolution is highly attractive, as it makes it possible for providing complementary, more complete tissue information on internal organs hard to access. Here we describe such a miniature endoscope only 1 mm in diameter that integrates photoacoustic imaging (PAI), optical coherence tomography (OCT), and ultrasound (US). The integration of PAI/OCT/US allows for high-resolution imaging of three tissue contrasts including optical absorption (PAI), optical scattering (OCT), and acoustic properties (US). We demonstrate the capabilities of this trimodal endoscope using mouse ear, human hand, and ...

      Read Full Article
    4. Non-moving scanner design for OCT systems

      Non-moving scanner design for OCT systems

      n this work, a novel beam scanner design based on non-moving parts is introduced which will eliminate the phase and inaccuracy problems of the mechanical scanners while providing two times imaging speed improvement for optical coherence tomography systems. The design is comprised of electro-optically activated switches that are placed on the sample arm. For the example considered here, lateral resolution of 20 µm, and lateral scanning range of 1 mm are aimed at which resulted in a scanner size of 1 mm × 9 mm. Due to its compact size, proposed design can also be implemented in forward-looking endoscopic probes.

      Read Full Article
    5. OCT probe with pivoting fiber

      OCT probe with pivoting fiber

      An OCT probe for imaging patient tissue may include an actuation system arranged to displace an optical fiber within a cannula. The actuation system may include a driver actuatable to displace a portion of the optical fiber, with the driver acting in an angled direction relative to the axis of the cannula. The actuation system also may include a pivot feature operably engaged with the optical fiber in a manner permitting the optical fiber to pivot on the pivot feature when the driver actuates to displace the portion of the optical fiber.

      Read Full Article
    6. Dual-path handheld system for cornea and retina imaging using optical coherence tomography

      Dual-path handheld system for cornea and retina imaging using optical coherence tomography

      A dual-path handheld system is proposed for cornea and retina imaging using spectral domain optical coherence tomography. The handheld sample arm is designed to acquire two images simultaneously. Both eyes of a person can be imaged at the same time to obtain the images of the cornea of one eye and the retina of the other eye. Cornea, retina, and optic disc images are acquired with the proposed sample arm. Experimental results demonstrate the usefulness of this system for imaging of different eye segments. This system reduces the time required for imaging of the two eyes and is cost effective.

      Read Full Article
    7. Endoscopic optical coherence tomography using compressive sensing

      Endoscopic optical coherence tomography using compressive sensing

      Conventionally endoscopic OCT images are reconstructed by uniform sampling in both axial and transverse direction of the image. To shorten the scanning time and reduce the acquisition data, we propose to sparsely sample the axial scans and use compressive sensing (CS) to reconstruct the full endoscopic OCT image with randomly chosen axial scans that are much less than conventional Nyquist criteria requirement. And we study the ratio of sparse sampling numerically and experimentally that are required to reconstruct acceptable OCT images. We demonstrate that the OCT image acquisition time can be significantly reduced because of much less acquired data.

      Read Full Article
    8. Two-axis polydimethylsiloxane-based electromagnetic microelectromechanical system scanning mirror for optical coherence tomography

      Two-axis polydimethylsiloxane-based electromagnetic microelectromechanical system scanning mirror for optical coherence tomography

      Compact size and fast imaging abilities are key requirements for the clinical implementation of an optical coherence tomography (OCT) system. Among the various small-sized technology, a microelectromechanical system (MEMS) scanning mirror is widely used in a miniaturized OCT system. However, the complexities of conventional MEMS fabrication processes and relatively high costs have restricted fast clinical translation and commercialization of the OCT systems. To resolve these problems, we developed a two-axis polydimethylsiloxane (PDMS)-based MEMS (2A-PDMS-MEMS) scanning mirror through simple processes with low costs. It had a small size of 15 × 15 × 15    mm 3 15×15×15  mm3 , was fast ...

      Read Full Article
    9. Miniaturization of plastic lens by injection molding for disposable endoscopie optical coherence tomography system

      Miniaturization of plastic lens by injection molding for disposable endoscopie optical coherence tomography system

      Minimally invasive robotic surgery required disposable endoscopie optical coherence tomography (OCT) for high-resolution deep tissue imaging and cross-contamination prevention. Here, we developed a miniaturized plastic lens by injection molding for developing a disposable endoscopie optical coherence tomography system for the first time. Injection molding provided low-cost and high-production rate to produce a disposable plastic lens and enabled the miniaturization of plastic lens. Transmittance and curvature of the plastic lens was measured. The plastic lens was integrated with an endoscopie OCT system, and the images of human-skin and microspheres embedded in agarose gel were captured. We are currently trying to integrate ...

      Read Full Article
      Mentions: Ki Hean Kim
    10. Method and apparatus for automated scanning probe microscopy

      Method and apparatus for automated scanning probe microscopy

      This invention concerns scanning probe microscopes and related instruments ("SPMs") when used to investigate or measure large samples whose size is a multiple of the typical operational scanning area of an SPM, say 150 .mu.m.times.150 .mu.m at most. To avoid frequent readjustments or other time-consuming human interaction and errors when focusing the SPM, a multi-step, automated method for the SPM-scanning of large samples is disclosed, comprising a "coarse", i.e. low resolution, non-SPM scanning or mapping step adapted to scan a large sample and providing an integral map of the sample, followed by a preferably mathematical ...

      Read Full Article
    11. Planar and Integrated MEMS Micromirrors Based Endoscopic Optical Coherence Tomography (Thesis)

      Planar and Integrated MEMS Micromirrors Based Endoscopic Optical Coherence Tomography (Thesis)

      Optical coherence tomography (OCT) is a thriving imaging modality which provides high-resolution, in vivo, real-time, non-invasive, cross-sectional imaging capability for biomedical applications. Over the past decade, OCT has become a standard clinical diagnosis tool for ophthalmology. However, human organs other than eyeballs are all highly scattering tissues, which limits the OCT penetration depth to ~2 mm. Therefore, endoscopic OCT probes with small diameter must be developed for imaging internal organs. The key component of an endoscopic OCT probe is the optical scanner. Thus, the first objective of this work is to develop miniature optical scanners using microelectromechanical system (MEMS) technology ...

      Read Full Article
    12. Micrometer-resolution in-fiber OCT probe with tunable working distance

      Micrometer-resolution in-fiber OCT probe with tunable working distance

      Optical coherence tomography (OCT) is an attractive modality in biomedical imaging systems due to its non-invasive imaging character. Since the image quality of OCT may be limited by the decrease of transverse resolution away from the focus spot, working distance tunable probe can be a strategy to overcome such limitation and maintain high transverse resolution at different imaging depths. In this paper, a miniature, working distance-tunable in-fiber OCT probe is demonstrated. The influences of the graded index fiber (GIF) length as well as the air cavity length on the working distance and the transverse resolution are simulated and discussed. Experimental ...

      Read Full Article
    13. Common-path optical coherence tomography using a microelectromechanical-system-based endoscopic probe

      Common-path optical coherence tomography using a microelectromechanical-system-based endoscopic probe

      This paper presents a common-path (CP) swept-source optical coherence tomography (SSOCT) system based on a special endoscopic probe design with an in-line internal reflection as the reference and a two-axis electrothermal microelectromechanical system mirror for image scanning. The rear surface of a gradient reflective index (GRIN) lens inside the probe is set as the reference reflection plane. The length of the GRIN lens is optimized to eliminate the artifacts in SSOCT images successfully. Doppler OCT is also demonstrated based on the CP endoscopic probe. The diameter of the probe is only 2.5 mm, so it can be easily inserted ...

      Read Full Article
    14. Tomography probe

      Tomography probe

      An optical probe suitable for medical or dental tomography is switchable between a rotating and non-rotating mode to control interference between source signals and data signals. The probe is suitably constructed in an in-line configuration and uses Faraday rotators which rotate polarization in the same direction in a rotating mode and rotate polarization in opposite directions in a non-rotating mode.

      Read Full Article
    15. University of Washington Receives NIH Grant for Needle Biopsy Preservation and Preparation for Rapid 2D Pathology of Pancreas

      University of Washington Receives NIH Grant for Needle Biopsy Preservation and Preparation for Rapid 2D Pathology of Pancreas

      University of Washington Receives a 2016 NIH Grant for $235,226 for Needle Biopsy Preservation and Preparation for Rapid 2D Pathology of Pancreas. The principal investigator is Eric Seibel. The program began in 2014 and ends in 2017. Below is a summary of the proposed work. There are over three million needle biopsies performed every year in the USA, typically for the diagnosis of breast, prostate, thyroid, lung, liver, and pancreatic cancers. Because needle biopsies are less invasive than surgical biopsies, they are much more cost-effective. However, a major limitation for all needle biopsies are that the pathologist or cytologist ...

      Read Full Article
    16. Astigmatism corrected common path probe for optical coherence tomography

      Astigmatism corrected common path probe for optical coherence tomography

      Background and Objectives Optical coherence tomography (OCT) catheters for intraluminal imaging are subject to various artifacts due to reference-sample arm dispersion imbalances and sample arm beam astigmatism. The goal of this work was to develop a probe that minimizes such artifacts. Materials and Methods Our probe was fabricated using a single mode fiber at the tip of which a glass spacer and graded index objective lens were spliced to achieve the desired focal distance. The signal was reflected using a curved reflector to correct for astigmatism caused by the thin, protective, transparent sheath that surrounds the optics. The probe design ...

      Read Full Article
    17. OCT probe using PZT

      OCT probe using PZT

      An optical coherence tomography (OCT) probe using lead zirconate titanate (PZT). In the OCT probe using PZT, a sine wave is induced from a vibrator made of a piezoelectric element, so that an image in which the scanning range is increased can be captured due to the vibration of the vibrator. A decrease in the vibration of the vibrator can be minimized by optimizing the position where the base fixes the vibrator.

      Read Full Article
    18. Circumferential optical coherence tomography angiography imaging of the swine esophagus using a micromotor balloon catheter

      Circumferential optical coherence tomography angiography imaging of the swine esophagus using a micromotor balloon catheter

      We demonstrate a micromotor balloon imaging catheter for ultrahigh speed endoscopic optical coherence tomography (OCT) which provides wide area, circumferential structural and angiographic imaging of the esophagus without contrast agents. Using a 1310 nm MEMS tunable wavelength swept VCSEL light source, the system has a 1.2 MHz A-scan rate and ~8.5 µm axial resolution in tissue. The micromotor balloon catheter enables circumferential imaging of the esophagus at 240 frames per second (fps) with a ~30 µm (FWHM) spot size. Volumetric imaging is achieved by proximal pullback of the micromotor assembly within the balloon at 1.5 mm/sec ...

      Read Full Article
    19. Deep tissue volume imaging of birefringence through fibre-optic needle probes for the delineation of breast tumour

      Deep tissue volume imaging of birefringence through fibre-optic needle probes for the delineation of breast tumour

      Identifying tumour margins during breast-conserving surgeries is a persistent challenge. We have previously developed miniature needle probes that could enable intraoperative volume imaging with optical coherence tomography. In many situations, however, scattering contrast alone is insufficient to clearly identify and delineate malignant regions. Additional polarization-sensitive measurements provide the means to assess birefringence, which is elevated in oriented collagen fibres and may offer an intrinsic biomarker to differentiate tumour from benign tissue. Here, we performed polarization-sensitive optical coherence tomography through miniature imaging needles and developed an algorithm to efficiently reconstruct images of the depth-resolved tissue birefringence free of artefacts. First ex ...

      Read Full Article
    20. Bimodal endoscopic probe combining white-light microscopy and optical coherence tomography

      Bimodal endoscopic probe combining white-light microscopy and optical coherence tomography

      We present a novel bimodal endoscopic imaging probe that can simultaneously provide full-field white-light video microscopy and confocal optical coherence tomography (OCT) depth scans. The two modalities rely on spectrally separated optical paths that run partially in parallel through a micro-optical bench system, which has a cross-section of only 2    mm × 2.76    mm and is realized via standard silicon micromachining techniques. With a numerical aperture of 0.061, the video modality has a resolution and field of view of 9.3 and 1240    μm × 1080    μm , respectively. The resolution is limited by the pixel spacing of the coherent fiber ...

      Read Full Article
    21. Combination optical and ultrasonic imaging of an eye

      Combination optical and ultrasonic imaging of an eye

      A method and apparatus are disclosed for integrating optical coherence tomography (OCT) and very high frequency ultrasound (VHFU) imaging systems. An OCT probe and reference arm are mounted along with an ultrasound probe on a carriage capable of rotational, linear, and/or arcuate motion. The probe carriage may be immersed in water or other suitable medium. The OCT and VHFU probes move about the cornea surface such that the probe axes are substantially perpendicular relative to the cornea surface throughout a scan. The probes are able to be scanned in an arcuate path across the entire cornea surface. The method ...

      Read Full Article
    22. Imaging probes and associated devices, systems, and methods utilizing speaker actuators

      Imaging probes and associated devices, systems, and methods utilizing speaker actuators

      Devices, systems, and methods that utilize a speaker to impart motion to an optical fiber positioned within an imaging probe are provided. In some embodiments, an ophthalmic imaging apparatus comprises an optical probe having a handle sized and shaped for handheld grasping by a user; and a cannula coupled to the handle, the cannula sized and shaped for insertion into an eye to be treated; an optical fiber positioned at least partially within the optical probe, the optical fiber configured to receive an imaging light from an imaging light source and guide the imaging light to an optical element positioned ...

      Read Full Article
    23. Spectrally encoded miniature endoscopic imaging probe

      Spectrally encoded miniature endoscopic imaging probe

      A spectrally encoded endoscopic probe having high resolution and small diameter comprising at least one flexible optical fiber; an energy source; a grating through which said energy is transmitted such that the energy spectrum is dispersed; a lens for focusing the dispersed energy spectrum onto a sample such that the impingement spot for each wavelength is a separate position on the sample, the wavelength spectrum defining a wavelength encoded axis; means for mechanically scanning the sample with focused energy in a direction perpendicular to the wavelength encoded axis; a means for receiving energy reflected from the sample; and, a means ...

      Read Full Article
    24. Imaging probes and associated devices, systems, and methods utilizing lever arm actuators

      Imaging probes and associated devices, systems, and methods utilizing lever arm actuators

      Devices, systems, and methods that utilize a mechanical structure, such as a lever arm or a flexure mechanism, and an electrically energizable member, such as an actuator, to impart motion to an optical fiber positioned within an imaging probe are provided. In some embodiments, an ophthalmic imaging probe can include a handle; a cannula coupled to the handle; an optical fiber positioned at least partially within the handle and the cannula, the optical fiber configured to receive an imaging light from an imaging light source and guide the imaging light to an optical element positioned within a distal portion of ...

      Read Full Article
    1-24 of 469 1 2 3 4 ... 18 19 20 »
  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) University of Illinois at Urbana-Champaign
    2. (1 articles) University of Florida
    3. (1 articles) Hanyang University
  4. People in the News

    1. (1 articles) Stephen A. Boppart
    2. (1 articles) Guillermo L. Monroy
    3. (1 articles) Huikai K. Xie
    4. (1 articles) Ryan L. Shelton
    5. (1 articles) Paritosh Pande
    6. (1 articles) Jin Won Kim
    7. (1 articles) Hongki Yoo