Abstract: A plasmonic phase modulator is provided. The modulator has a conductive layer, and a dielectric layer disposed on the conductive layer. A plasmonic layer is disposed on the dielectric layer. A plasmonic layer is disposed on the dielectric layer. The plasmonic layer is conductive to surface plasmon polariton (SPP) waves. The plasmonic layer may be, for example, a graphene sheet. A voltage signal source is operatively connected between the conductive layer and the plasmonic layer for modulating a propagation speed of an SPP wave propagating on the plasmonic layer.

Abstract: A method of superimposing N optical transmission modes for collective transmission along a multimode optical fiber is provided where each of the N optical signals comprises N distinct superimposed transmission modes (M1, M2, . . . ) and a portion of each of the N propagating optical signals is sampled at a receiving end of the data transmission network. N2?1 distinct measurement conditions are derived from a transmission matrix T and a special unitary matrix group SU(N) corresponding to the superimposed transmission modes (M1, M2, . . . ) at the receiving end of the data transmission network and N2?1 measurements are extracted from the sampled signals. The extracted N2?1 measurements are used to solve a matrix equation corresponding to the generated SU(N) matrices and the output matrix transposed and used to generating principal state launch conditions from the eigenvectors of the transposed output matrix to form a principal state in each of the N optical signals.

Abstract: A multicore optical component and corresponding methods of converting a linearly or circularly polarized Gaussian beam of light into a radially or azimuthally polarized beam of light are provided. The multicore optical component comprises a plurality of birefringent, polarization maintaining elliptical cores. The elliptical cores collectively define an azimuthally varying distribution of major axes where the orientation of the major axis of a given elliptical core is given by ?=(180/N)*n+? where n is the core number and ? is any angle greater than 0°.

Abstract: The present invention provides systems and methods for non-destructively detecting material abnormalities beneath a coated surface, comprising a mid-infrared (MIR) detection unit for illuminating an area of the coated surface and detecting light reflected from the illuminated area of the coated surface, and a processing unit for producing an image from optical characteristics received from the MIR detection unit. In addition, the system may further comprise a scanning unit for moving the MIR detection unit to a next area.

Abstract: The present invention provides systems and methods for non-destructively detecting material abnormalities beneath a coated surface, comprising a mid-infrared (MIR) detection unit for illuminating an area of the coated surface and detecting light reflected from the illuminated area of the coated surface, and a processing unit for producing an image from optical characteristics received from the MIR detection unit. In addition, the system may further comprise a scanning unit for moving the MIR detection unit to a next area.

Abstract: A method for monitoring a biological tissue includes illuminating the tissue, including a fluorophore, with a wavelength of light, the wavelength selected for exciting the fluorophore, determining a fluorescent emission of the fluorophore, the emission indicating the presence of the fluorophore, and correlating an emission of the fluorophore to an extent and degree of damage to the tissue. Damage to the tissue includes a breakdown of the fluorophore, resulting in a reduced level of emission. The fluorophore can include one of collagen and elastin. The fluorophore can include tryptophan, nicotinamide adenine dinucleotide, flavin and porphyrin. Correlating the emission of the fluorophore to the extent and degree of damage further includes processing a correlation of the emission over time, controlling the power of a laser welder based on the processed correlation, and preventing overheating of the tissue by the laser welder.

Abstract: Method and apparatus for examining biological materials using diffuse reflectance spectroscopy and the Kubelka-Munk function. In one aspect, the method is used to determine whether a tissue sample is cancerous or not and comprises the steps of (a) measuring the diffuse reflectance from the tissue sample at a first wavelength and at a second wavelength, wherein the first wavelength is a wavelength selected from the group consisting of 255-265 nm and wherein the second wavelength is a wavelength selected from the group consisting of 275-285 nm; (b) using the Kubelka-Munk function to transform the diffuse reflectance measurement obtained at the first and second wavelengths; and (c) comparing a ratio or a difference of the transformed Kubelka-Munk measurements at the first and second wavelengths to appropriate standards determine whether or not the tissue sample is cancerous.

Abstract: An apparatus for use in examining an object, such as skin, mucosa and cervical tissues for the purpose of detecting cancer and precancerous conditions therein. In one embodiment, the apparatus includes a gun-shaped housing having a handle portion and a barrel portion. The front end of the barrel portion is open, and a glass cover is mounted therein. Red, green, blue, and white LED's are disposed within the handle portion of the housing and are electrically connected to a battery also disposed within the handle portion of the housing. A manually-operable switch for controlling actuation of each of the four LED's is accessible on the handle portion of the housing. An optical fiber is disposed inside the housing and is used to transmit light from the four LED's through a first polarizer disposed in the barrel portion of the housing and then through the glass cover to illuminate a desired object.

Abstract: A system for non-destructively imaging surfaces through a coating, in accordance with the present invention, includes a near-infrared (NIR) light source for illuminating a coated surface. A detector is positioned in an operative relationship with the NIR light source to receive light backscattered from the coated surface and from the coating. A gating device is positioned in an operative relationship with the detector to selectively permit light to pass to the detector to measure optical characteristics of the backscattered light such that determinations of a state of a surface below the coating is determined based on the optical characteristics of the backscattered light. Methods for performing the non-destructive imaging of the present invention are also disclosed.

Abstract: This invention relates to the novel identification of myelin-associated glycoprotein (“MAG”) as a potent inhibitor of neural regeneration. More particularly, this invention relates to compositions and methods useful for reversing inhibition of neural regeneration in the central and peripheral nervous system. Assays to monitor the effects of MAG on neural regeneration and to identify agents which will block or promote the inhibitory effects of MAG on neural outgrowth are provided. Screening methods for identifying such agents are also provided. This invention also relates to compositions and methods using agents that can reverse the inhibitory effects of MAG on neural regeneration.

Abstract: This invention relates to the novel identification of myelin-associated glycoprotein (“MAG”) as a potent inhibitor of neural regeneration. More particularly, this invention relates to compositions and methods useful for reversing inhibition of neural regeneration in the central and peripheral nervous system. Assays to monitor the effects of MAG on neural regeneration and to identify agents which will block or promote the inhibitory effects of MAG on neural outgrowth are provided. Screening methods for identifying such agents are also provided. This invention also relates to compositions and methods using agents that can reverse the inhibitory effects of MAG on neural regeneration.

Abstract: A method for imaging objects in a highly scattering turbid medium, such as breast, brain, prostate in human body and clouds, smoke in atmosphere environment, using backscattered light. The method involves using a group of sources and detectors setting on same side of medium to generate a plurality of time-resolved intensity data of backscattered light from the medium. The inverse computation using a reconstruction algorithm, taking the measured data as input, produces a three-dimensional image map of the internal structure of a turbid medium.

Abstract: A method and system for examining biological materials using low-power cw excitation Raman spectroscopy. In accordance with the teachings of the invention, a low-power continuous wave (cw) pump laser beam and a low-power cw Stokes (or anti-Stokes) probe laser beam simultaneously illuminate a biological material and traverse the biological material in collinearity. The pump beam, whose frequency is varied, is used to induce Raman emission from the biological material. The intensity of the probe beam, whose frequency is kept constant, is monitored as it leaves the biological material. When the difference between the pump and probe excitation frequencies is equal to a Raman vibrational mode frequency of the biological material, the weak probe signal becomes amplified by one or more orders of magnitude (typically up to about 10.sup.4 -10.sup.6) due to the Raman emission from the pump beam.

Abstract: A fiberoptic assembly for optical spectroscopic analysis of a sample. In a preferred embodiment, the assembly is well-suited for use inside the working channel of an endoscope and comprises a tubular outer jacket and a tubular inner jacket, the inner jacket being coaxial with and positioned inside the outer jacket. The open front end of the inner jacket is spaced rearwardly a short distance relative to the open front end of the outer jacket. The outer jacket has an outer diameter of approximately 2.2 mm. The assembly also includes a plug made of fused silica. The plug has a front cylindrical portion of comparatively large cross-sectional diameter and a rear cylindrical portion of comparatively small cross-sectional diameter. The front portion is mounted within the outer jacket by a friction-fit and extends longitudinally from the open front end thereof to the open front end of the inner jacket.

Abstract: This invention relates to the novel identification of myelin-associated glycoprotein ("MAG") as a potent inhibitor of neural regeneration. More particularly, this invention relates to compositions and methods useful for reversing inhibition of neural regeneration in the central and peripheral nervous system. Assays to monitor the effects of MAG on neural regeneration and to identify agents which will block or promote the inhibitory effects of MAG on neural outgrowth are provided. Screening methods for identifying such agents are also provided. This invention also relates to compositions and methods using agents that can reverse the inhibitory effects of MAG on neural regeneration.