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SBIR Final Report. Liquid Core Optical Scintillating Fibers

Description: This Phase I SBIR project focused on developing flexible scintillating liquid core optical fibers, with potential uses in high-energy calorimetry, tracking, preradiators, active targets or other fast detectors. Progress on the six tasks of the project is summarized. The technical developments involve three technology components: (1) highly flexible capillaries or tubes of relatively low n (index of refraction) to serve as cladding and liquid core containment; (2) scintillator (and clear) fluids of relatively high n to serve as a core-- these fluids must have a high light transmission and, for some applications, radiation hardness; (3) optical end plugs, plug insertion, and plug-cladding tube sealing technology to contain the core fluids in the tubes, and to transmit the light.
Date: May 16, 2000
Creator: Beetz, C.P.; Steinbeck, J. & Buerstler, R.
Partner: UNT Libraries Government Documents Department

Limitations on High Data Rate Optical Fiber Transmission Systems Due to Transmission Impairment

Description: This project supplemented our regular DOE grant from the Basic Energy Sciences organization with the goal of fostering industrial partnerships and student internships. During the project period, we have interacted with between 15 and 20 companies in the optical fiber telecommunications equipment industry, and our students have participated in a number of highly visible projects with companies such as Ciena, Science Applications International Corporation, KDD, ATT, Virtual Photonics, Inc., Phaethon Telecommunications, PhotonEx, and others. The project led to many successful interactions and numerous job offers for our students.
Date: March 15, 2002
Creator: Menyuk, Curtis R.
Partner: UNT Libraries Government Documents Department

Measurements at 351 nm of temporal dispersion in fibers

Description: 1. Temporal dispersion at 351-nm was measured in the following: a 35-m bundle of 19 each 50-µm-core fibers, a companion 35-m single fiber, a 100-µm-core single fiber (at 4 lengths), and a 50-µm-core single fiber (two samples, 7 lengths). The 50-µm-core fiber was from preform #24; the 100-µm-core fiber was a prototype version having a thick cladding. All of the fibers were developed and manufactured at the Vavilov State Optical Institute, St. Petersburg, Russia. 2. Dispersion measurements were made by propagating a 20-ps 351-nm pulse through the fiber under test and recording the output on an S20 streak camera. The width of the pulse transmitted by the fiber was compared to that of a fraction of the pulse that had propagated over an air path. Values of dispersion were calculated as, D = {radical}(F² - A²) , where F and A are the full widths at half maximum (FWHM) for, respectively, the fiber-path and the air-path streaks. 3. In each of the experiments, the measured dispersion increased with counts in the streak record, which in principle, are proportional to intensity in the fiber. Measured values of dispersion ranged from about 0.6 to 1.0 ps/m for the single fibers. 4. The measured FWHMs of both the fiber-path pulse and the air-path pulse increased with increase in counts in the streak record. The rate of broadening was greatest for the fiber-path pulse, and the broadening of that pulse was the primary cause for the dependence of dispersion on counts in the streak record. Pulse broadening with increase in counts is symptomatic of camera saturation, but it is difficult to understand why saturation should have effected the fiber-path pulses more strongly. 5. There were spatial anomalies in the streak records of the output pulses from some of the fibers. Emission by the bundle ...
Date: November 4, 1998
Creator: Griffith, R; Milam, D; Sell, W & Thompson, C
Partner: UNT Libraries Government Documents Department

Fabricating Optical Fiber Imaging Sensors Using Inkjet Printing Technology: a pH Sensor Proof-of-Concept

Description: We demonstrate the feasibility of using Drop-on-Demand microjet printing technology for fabricating imaging sensors by reproducibly printing an array of photopolymerizable sensing elements, containing a pH sensitive indicator, on the surface of an optical fiber image guide. The reproducibility of the microjet printing process is excellent for microdot (i.e. micron-sized polymer) sensor diameter (92.2 {+-} 2.2 microns), height (35.0 {+-} 1.0 microns), and roundness (0.00072 {+-} 0.00023). pH sensors were evaluated in terms of pH sensing ability ({le}2% sensor variation), response time, and hysteresis using a custom fluorescence imaging system. In addition, the microjet technique has distinct advantages over other fabrication methods, which are discussed in detail.
Date: March 1, 2005
Creator: Carter, J C; Alvis, R M; Brown, S B; Langry, K C; Wilson, T S; McBride, M T et al.
Partner: UNT Libraries Government Documents Department

Adaptive control of femtosecond pulse propagation in optical fibers

Description: We present an adaptive control loop that synthesizes fs-pulses that are self-correcting for higher order nonlinear effects when launched in a conventional single-mode fiber, nearly preserving the initial (t{approx}200 fs) pulse duration.
Date: January 1, 2001
Creator: Omenetto, F. G. (Fiorenzo G.); Taylor, Antoinette J.,; Moores, M. D. (Mark D.) & Reitze, David H.
Partner: UNT Libraries Government Documents Department

938 nm Nd-Doped High Power Cladding Pumped Fiber Amplifier

Description: 2.1W of 938nm light has been produced in an Nd{sup 3+} doped fiber amplifier. Wavelength dependent bend losses can be employed to minimize 1088nm amplified spontaneous emission giving the optical fiber a distinct advantage over bulk media.
Date: September 19, 2002
Creator: Dawson, J; Beach, R; Drobshoff, A; Liao, Z; Pennington, D; Payne, S et al.
Partner: UNT Libraries Government Documents Department

First Field Trial of Optical Label-Based Switching and Packet Drop on a 477km NTON/Sprint Link

Description: We demonstrate the first field trial of optical label-based wavelength switching and packet drop on 476.8km of the National Transparent Optical Network. Subcarrier multiplexed labels control a switch fabric that includes a tunable wavelength converter and arrayed waveguide grating router.
Date: December 10, 2001
Creator: Hernandez, V J; Pan, Z; Cao, J; Tsui, V K; Bansal, Y; Fong, S K H et al.
Partner: UNT Libraries Government Documents Department

GFOC Project results: High Temperature / High Pressure, Hydrogen Tolerant Optical Fiber

Description: Tests results are given for exposure of multimode optical fiber to high temperatures (300 deg. C) and high partial pressure (15 bar) hydrogen. These results demonstrate that fluorine down doped optical fibers are much more hydrogen tolerant than traditional germanium doped multimode optical fibers. Also demonstrated is the similar hydrogen tolerance of carbon coated and non-carbon coated fibers. Model for reversible H2 impact in fiber versus T{sup o}C and H2 pressure is given. These results have significant impact for the longevity of use for distributed temperature sensing applications in harsh environments such as geothermal wells.
Date: February 12, 2012
Creator: Burov, E.; Pastouret, A.; Aldea, E.; Overton, B.; Gooijer, F. & Bergonzo, A.
Partner: UNT Libraries Government Documents Department

Laser Injection Optics for High-Intensity Transmission in Multimode Fibers

Description: An increasing number of applications are requiring fiber transmission of high-intensity laser pulses. The authors particular interests have led them to examine carefully the fiber transmission of Q-switched pulses from multimode Nd:YAG lasers at their fundamental wavelength. The maximum pulse energy that can be transmitted through a particular fiber is limited by the onset of laser-induced breakdown and damage mechanisms. Laser breakdown at the fiber entrance face is often the first limiting process to be encountered, but other mechanisms can result in catastrophic damage at either fiber face, within the initial entry segment of the fiber, and at other internal sites along the fiber path. In the course of their studies they have examined a number of factors that govern the relative importance of different mechanisms, including laser characteristics, the design and alignment of injection optics, fiber end-face preparation, and fiber routing. The present study emphasizes the important criteria for injection optics in high-intensity fiber transmission, and illustrates the opportunities that now exist for innovative designs of optics to meet these criteria. The consideration of diffractive optics to achieve desired injection criteria began in 1993, and they have evaluated a progression of designs since that time. In the present study, two recent designs for injection optics are compared by testing a sufficient number of fibers with each design to establish statistics for the onset of laser-induced breakdown and damage. In this testing they attempted to hold constant other factors that can influence damage statistics. Both designs performed well, although one was less successful in meeting all injection criteria and consequently showed a susceptibility to a particular damage process.
Date: August 29, 2000
Creator: SETCHELL,ROBERT E.
Partner: UNT Libraries Government Documents Department

CLASP (Capture and Locking alignment Spring Positioner): A micromachined fiber auto-positioning device

Description: This work provides a method of mechanical alignment of an array of single mode fibers to an array of optical devices. The technique uses a micromachined metal spring, which captures a vertical, pre- positioned fiber, moves it into accurate alignment, and holds it for attachment. The spring is fabricated from electroplated mickel, using photodefined polyimide as a plating mask. The nickel is plated about 80 {mu}m thick, so that a large fiber depth is captured. In one application, the nickel springs can be aligned to optics on the back side of the substrate. This entire concept is referred to as CLASP (Capture and Locking Alignment Spring Positioner). These springs can be used for general alignment and capture of any fiber to any optical input or output device. Passive alignment of fiber arrays to {plus}/{minus} 2{mu}m accuracy has been demonstrated, with a clear path to improved accuracy.
Date: March 1, 1996
Creator: Kravitz, S. H.; Word, J. C.; Bauer, T. M.; Seigal, P. K. & Armendariz, M. G.
Partner: UNT Libraries Government Documents Department

DETECTION OF UNAUTHORIZED CONSTRUCTION EQUIPMENT IN PIPELINE RIGHT-OF-WAYS

Description: Natural gas transmission companies mark the right-of-way areas where pipelines are buried with warning signs to prevent accidental third-party damage. Nevertheless, pipelines are sometimes damaged by third-party construction equipment. A single incident can be devastating, causing death and millions of dollars of property loss. This damage would be prevented if potentially hazardous construction equipment could be detected, identified, and an alert given before the pipeline was damaged. The Gas Technology Institute (GTI) is developing a system to solve this problem by using an optical fiber as a distributed sensor and interrogating the fiber with an optical time domain reflectometer. Key issues are the ability to detect encroachment and the ability to discriminate among potentially hazardous and benign encroachments. The work performed in the second quarter of the project includes design of the instrument, selection of the key components, and beginning programming of the custom optical time domain reflectometer. Work included an assessment of two other approaches to measuring strain and vibrations in an extended optical fiber sensor.
Date: April 26, 2002
Creator: Huebler, James E.
Partner: UNT Libraries Government Documents Department

DETECTION OF UNAUTHORIZED CONSTRUCTION EQUIPMENT IN PIPELINE RIGHT-OF-WAYS

Description: Natural gas transmission companies mark the right-of-way areas where pipelines are buried with warning signs to prevent accidental third-party damage. Nevertheless, pipelines are sometimes damaged by third-party construction equipment. A single incident can be devastating, causing death and millions of dollars of property loss. This damage would be prevented if potentially hazardous construction equipment could be detected, identified, and an alert given before the pipeline was damaged. The Gas Technology Institute (GTI) is developing a system to solve this problem by using an optical fiber as a distributed sensor and interrogating the fiber with a custom optical time domain reflectometer. Key issues are the ability to detect encroachment and the ability to discriminate among potentially hazardous and benign encroachments. The work performed in the 4th quarter of 2002 included fine-tuning and debugging of the custom Optical Time Domain Reflectometer being constructed for data collection and analysis. It also included installation of optical fibers at the test site along an operating pipeline.
Date: January 29, 2003
Creator: Huebler, James E.
Partner: UNT Libraries Government Documents Department

DETECTION OF UNAUTHORIZED CONSTRUCTION EQUIPMENT IN PIPELINE RIGHT-OF-WAYS

Description: Natural gas transmission companies mark the right-of-way areas where pipelines are buried with warning signs to prevent accidental third-party damage. Nevertheless, pipelines are sometimes damaged by third-party construction equipment. A single incident can be devastating, causing death and millions of dollars of property loss. This damage would be prevented if potentially hazardous construction equipment could be detected, identified, and an alert given before the pipeline was damaged. The Gas Technology Institute (GTI) is developing a system to solve this problem by using an optical fiber as a distributed sensor and interrogating the fiber with a custom optical time domain reflectometer. Key issues are the ability to detect encroachment and the ability to discriminate among potentially hazardous and benign encroachments. The work performed in the third quarter of the project (2nd quarter of 2002) includes design and construction of the diode laser driver and high-speed detector electronics. Fine-tuning of the electronics is proceeding. A new test site along an operating pipeline has been obtained.
Date: October 30, 2002
Creator: Huebler, James E.
Partner: UNT Libraries Government Documents Department

Development of the indicator-photopolymer chemistries for multianalyte sensor arrays

Description: Remediation of ground and waste water facilities requires the analysis of the pollutants. Multianalyte fiber-optic chemical sensors based on indicators have been developed, with multiple indicators immobilized at the distal end of a single imaging fiber. By coupling the imaging fibers to a charge coupled device detector, one can spatially and spectrally discriminate the multiple sensing sites and hence monitor multiple analyte concentrations simultaneously. This report describes the development of the indicator chemistry and immobilization procedures developed for pH, Al{sup 3+}, and hydrocarbons. A polymer matrix is used to mass transfer the analyte to the indictor.
Date: January 1, 1995
Creator: Healey, B.G.; Chadha, S.; Walt, D.R.; Richards, J.B.; Brown, S.B. & Milanovich, F.P.
Partner: UNT Libraries Government Documents Department

Polishing optical fibers for the D0 ICD in Run II

Description: The active element in the Run II D0 Inter Cryostat Detector (ICD) is an array of scintil- lator tiles. Charged and neutral particles produce light in the tiles which is transported to the photodetection system along optical fiber pathways. In general, building a tile/fiber detector requires very conscientious technical support and a high degree of quality control. Polishing fibers is one of the most delicate of tasks involved. This note describes methods used by the ICD group to polish the ends of fibers. These methods may be used in the ICD production as well as in prototype development.
Date: December 1, 1998
Creator: Li, Elizabeth Gallas and Jia
Partner: UNT Libraries Government Documents Department

Two-color mid-infrared thermometer using a hollow glass optical fiber

Description: A non-invasive two-color infrared thermometer has been developed for low-temperature biomedical applications. Mid-infrared radiation from the target is collected via a single 700 {mu}m-bore hollow glass optical fiber, simultaneously split into two paths and modulated by a gold-coated reflective optical chopper, and focused onto two thermoelectrically-cooled HgCdZnTe photoconductors (bandpasses of 2- 6 {mu}m and 2-12 {mu}m, respectively) by gold-coated spherical mirrors. The small numerical aperture of the hollow glass fiber provides high spatial resolution (is less than 1 mm), and the hollow bore eliminates reflective losses. The modulated detector signals are recovered using lock-in amplification, permitting measurement of small low-temperature signal buried in the background. A computer algorithm calculates the true temperature and emissivity of the target in real time based on a previous blackbody (emissivity equal to 1) calibration, taking into account reflection of the ambient radiation field from the target surface.
Date: June 30, 1997
Creator: Small, W., IV.; Celliers, P.M.; Da Silva, L.D. & Matthews, D.L.
Partner: UNT Libraries Government Documents Department

Observation of stimulated raman scattering in an optical fiber at the Fermilab A0 photoinjector

Description: We have observed stimulated Raman scattering in a 2 km long optical fiber injected with an 81 MHz train of {approximately}80 ps pulses from a modelocked Nd:YLF oscillator operating at {lambda} = 1054 nm.
Date: September 1, 1998
Creator: Fry, A.R.; Taylor, B.; Fitch, M.J. & Melissinos, N.C., Fermilab
Partner: UNT Libraries Government Documents Department

Fabrication, measurement, and alignment uniformity analysis of linear arrays of optical fibers

Description: Techniques were developed for assembling a linear array of optical fibers between two silicon plates and polishing the fiber ends in a plane perpendicular to the fiber axis. The silicon plates contained etched V-grooves for capturing the fibers. Optical fibers from two sources were evaluated, along with silicon plates supplied by two sources. Most of the arrays were assembled by epoxy bonding, but some effort was made to form a eutectic bond using gold metallized fibers with gold-coated silicon plates. Measurements were made of the uniformity of spacing of the fiber mode field centers in the linear array. The work was performed to develop a multi-fiber linear array connector to couple optical signals to and from optoelectronic devices.
Date: June 1, 1997
Creator: Klingsporn, P.E.
Partner: UNT Libraries Government Documents Department

Technical design report for the upgrade of the ICD for D-Zero Run II

Description: The Inter Cryostat Detector (ICD) used in Run I of the D0 Experiment will be inoperable in the central, high magnetic field planned for Run II. In Run I, the ICD enhanced the hermeticity and uniformity of the D0 calorimeter system, improving both missing transverse energy and jet energy resolution. The goals for the Run II ICD are the same. In this document, the physics arguments for maintaining the ICD are presented, followed by a detailed description of the planned design changes, prototype tests, construction, installation, and commissioning of the device for the Run II D0 detector. Estimates of costs and schedule can be found on //DOSERVER2/Operations/Upgrade Project/ subareas available via DZERO`s WinFrame Program Manager. This detector is not intended to provide any ``L0`` capabilities (for luminosity monitoring), or to provide any EM coverage in the intermediate region, or to provide additional coverage in the intermediate regions, unlike previous upgrades proposed in this detector region. The ICD upgrade described here maintains most of the Run I capabilities in a high magnetic field environment.
Date: January 1, 1998
Creator: Sawyer, L. & De, K.
Partner: UNT Libraries Government Documents Department

Light collection from scintillation counters using WLS fibers and bars

Description: Several methods of collecting light on scintillation counters using WLS fibers and WLS bars were studied. Nearly 20 prototype counters with different designs and with sizes ranging from 14{times}11{times}1.3cm{sup 3} to 105{times}60{times}1.3cm{sup 3} have been tested using cosmic muons and radioactive source. The efficiency of light collection on number of photoelectrons, uniformity of response, and time resolution have been measured. Test results for two new designs of light collection from scintillator based on WLS fibers around perimeter of scintillator plate and WLS fibers placed in machined on scintillator plate deep grooves are presented. Two out of the studied designs have been chosen as the basic options for the D0 muon system upgrade: light collection using two WLS bars for the forward muon scintillation counters and light collection using WLS fibers in deep grooves on scintillator for central area muon counters.
Date: January 1, 1998
Creator: Evdokimov, V.
Partner: UNT Libraries Government Documents Department

Comparison of fiber polishing techniques

Description: Many D0 Run II detectors currently in production rely on scintillating tile and fiber technology. In general, light from active scintillating elements or calibration signals is transported to the photodetection system along optical fiber pathways. Building a tile/fiber detector requires very conscientious technical support and a high degree of quality control; polishing fibers is one of the most delicate of tasks involved. This note compares three methods used to polish Hewlett Packard HFBR-RUS500 fiber. This type of fiber is expected to be used in both the Muon Scintillator Counters (MSC) and the InterCryostat Detector (ICD) calibration systems to transport light from the LED distribution block to the photomultiplier tubes.
Date: March 30, 1999
Creator: P.Hanlet, M.Marcus, E.Gallas and C. Lindenmeyer
Partner: UNT Libraries Government Documents Department