Abstract: The invention provides optical switching-based systems and methods for catheter-based optical diagnosis which are particularly well suited to determining the condition of blood vessels, including the state of the vessels with respect to atherosclerosis and its development. Various embodiments provide catheter-based spectroscopic systems that are configured to cycle between different optical interrogation techniques such as Raman spectroscopy, optical coherence tomography and time-resolved laser-induced fluorescence spectroscopy. One embodiment of the invention provides an intravascular catheter-based diagnostic system that cycles between fingerprint region (200-2,500 cm?1) Raman spectroscopy and high-wavenumber region (2,500-4,000 cm?1) Raman spectroscopy.

Abstract: The invention provides unitary optics modules that integrate several light management functions for performing optical spectroscopy, such as Raman spectroscopy, and optical spectroscopy systems that include one or more of the unitary optics modules. Methods of using the modules and systems are also provided.

Abstract: The present invention provides apparatuses and methods for sample analysis, such as tissue analysis, that integrate high wavenumber (HW) Raman spectroscopy for chemical composition analysis and optical coherence tomography (OCT) to provide depth and morphological information. The invention also provides side-viewing optical probes that are based on a single double clad optical fiber for performing the combined HW Raman spectroscopy and OCT. Intravascular catheter embodiments and related vascular diagnostic methods are also provided.

Abstract: The present invention provides apparatuses and methods for sample analysis, such as tissue analysis, that integrate high wavenumber (HW) Raman spectroscopy for chemical composition analysis and spectral-domain optical coherence tomography (SD-OCT) to provide depth and morphological information. Intravascular catheter embodiments and related vascular diagnostic methods are also provided.

Abstract: A chirped pulse amplification (CPA) system and method is described wherein a pulse selector is added after a final amplifier in the system. The pulse selector is configured to select amplified pulses such that the system output repetition rate of the CPA system is below an ASE-limiting repetition rate of the amplifiers. The system may also comprise pulse pickers placed before the final amplifier to control pulse energy of the amplified pulses.

Abstract: The invention provides hybrid basket-type intravascular catheter probes designed to optimize blood vessel wall contact or close proximity while traversing tortuous curves. Related diagnostic systems and methods are also provided.

Abstract: The present invention generally concerns the use of Bragg optical fibers in chirped pulse amplification systems for the production of high-pulse-energy ultrashort optical pulses. A gas-core Bragg optical fiber waveguide can be advantageously used in such systems to stretch the duration of pulses so that they can be amplified, and/or Bragg fibers can be used to compress optical signals into much shorter duration pulses after they have been amplified. Bragg fibers can also function as near-zero-dispersion delay lines in amplifier sections.

Abstract: The invention provides unitary optics modules that integrate several light management functions for performing optical spectroscopy, such as Raman spectroscopy, and optical spectroscopy systems that include one or more of the unitary optics modules. Methods of using the modules and systems are also provided.

Abstract: Optical and optoelectronic articles incorporating an amorphous diamond-like film are disclosed. Specifically, the invention includes optical or optoelectronic articles containing an amorphous diamond-like film overlying two or more proximate substrates, and to methods of making optical and optoelectronic articles. In certain implementations, the film comprises at least about 30 atomic percent carbon, from about 0 to about 50 atomic percent silicon, and from about 0 to about 50 atomic percent oxygen on a hydrogen-free basis. Another embodiment includes optical or optoelectronic articles containing an amorphous diamond-like film that is further coated with a metallic or polymeric material for attachment to a device package.

Abstract: The present invention provides apparatuses and methods for sample analysis, such as tissue analysis, that integrate high wavenumber (HW) Raman spectroscopy for chemical composition analysis and optical coherence tomography (OCT) to provide depth and morphological information. The invention also provides side-viewing optical probes that are based on a single double clad optical fiber for performing the combined HW Raman spectroscopy and OCT. Intravascular catheter embodiments and related vascular diagnostic methods are also provided.

Abstract: Methods for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.

Abstract: The present invention generally concerns the use of Bragg optical fibers in chirped pulse amplification systems for the production of high-pulse-energy ultrashort optical pulses. A gas-core Bragg optical fiber waveguide can be advantageously used in such systems to stretch the duration of pulses so that they can be amplified, and/or Bragg fibers can be used to compress optical signals into much shorter duration pulses after they have been amplified. Bragg fibers can also function as near-zero-dispersion delay lines in amplifier sections.

Abstract: Methods and apparatus for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.

Abstract: Optical and optoelectronic articles incorporating an amorphous diamond-like film are disclosed. Specifically, the invention includes optical or optoelectronic articles containing an amorphous diamond-like film overlying two or more proximate substrates, and to methods of making optical and optoelectronic articles. In certain implementations, the film comprises at least about 30 atomic percent carbon, from about 0 to about 50 atomic percent silicon, and from about 0 to about 50 atomic percent oxygen on a hydrogen-free basis. Another embodiment includes optical or optoelectronic articles containing an amorphous diamond-like film that is further coated with a metallic or polymeric material for attachment to a device package.

Abstract: A device used for dispersion compensation of a plurality of optical signals passing through an optical transmission line. The device includes a photosensitive optical fiber including a long length, chirped Bragg grating providing dispersion compensation over a wide bandwidth of optical signals. The long length chirped Bragg grating has a reflection bandwidth greater than about 25 nm, and further has reduced distortion at a bit rate of about 10?9. This reduced distortion leads to a power penalty of less than 3 dB during less than 25 nm stepwise changes in wavelength of the plurality of optical signals across the wide bandwidth. The device provides a dispersion greater than about 100 ps/nm in a optical transmission line operating at 10 Gbit/s.

Abstract: An apparatus that exposes only a selected portion of a length of optical fiber to a hydrogen atmosphere loading process. The apparatus includes a loading chamber that encloses at least the selected portion of the optical fiber and contains a hydrogen hydrogen atmosphere. At least one heating element regionally heats the hydrogen atmosphere surrounding the selected portion. The heating element may heat the hydrogen atmosphere to a temperature of at least 250° C.

Abstract: A method and apparatus are provided for generating short (e.g., picosecond) pulses using a 2 section 1553 nm DBR laser without gain switching nor external modulation. The center wavelength of the DBR section is modulated at 0.5 GHz to generate a constant amplitude frequency modulated optical wave Large group velocity dispersion is then applied with a chirped fiber Bragg grating to convert the FM signal to a pulse stream.

Abstract: A method for adjusting a photosensitive optical waveguide having an optical path length to a stabilized desired optical path length. The method includes the step of changing the optical path length of the photosensitive optical waveguide by exposing at least a first portion of the waveguide to actinic radiation and creating an induced index change in the exposed first portion. The waveguide then is subjected to an annealing cycle that stabilizes the waveguide. After the step of stabilizing the waveguide, the optical path length is adjusted by subjecting at least a selected part of the exposed first portion of the waveguide to a localized heating sufficient to change the refractive index at the selected part until the desired optical path length is achieved.

Abstract: A method for screening the quality of an optical component including the step of simulating the performance of the optical component. The step of simulating includes the step of measuring the optical phase &phgr; of the optical component, wherein the step of measuring comprises indirectly measuring the optical phase &phgr; of the optical component using a scanning laser having a scanning step size &Dgr;&ohgr; and a modulation frequency &ohgr;m such that &Dgr;&ohgr;/&ohgr;m≦2. The light throughput R of the optical component is then measured. A transfer function H as a function of optical frequency &ohgr; is constructed where H(&ohgr;)=R(&ohgr;)exp[j&phgr;(&ohgr;)], and the performance is simulated using the measured value of the optical phase and the light throughput into the transfer function.

Abstract: A method for increasing the photosensitivity of a selected portion of an optical fiber and for producing a grating in the selected portion of an optical fiber. The method includes the step of placing the selected portion of the optical fiber in a hydrogen containing atmosphere. The volume of the hydrogen-containing atmosphere immediately surrounding only the selected portion of the optical fiber is heated to a temperature of at least 250° C. Only the selected portion of the optical fiber is exposed to the heated volume of the hydrogen-containing atmosphere at a temperature of at least 250° C. for a predetermined time.