Gwangju Institute of Science and Technology

Dug Young Kim

Dongsoo Lee

Dong Ju Lee

In Hee Shin

Seung Bum Cho

Tae Jung Ahn

Sucbei Moon

Ji Yong Lee

Disclosed is an apparatus for measuring a fluorescence lifetime. The apparatus for measuring the fluorescence lifetime comprises an excitation light generator that generates excitation light to be irradiated on a sample including fluorescence molecules; a fluorescence photon collecting unit that collects a plurality of fluorescence photons generated by irradiating the excitation light on the sample; a light sensor that converts the collected fluorescence photons into a fluorescence electrical signal; and a fluorescence lifetime signal processor that determines the fluorescence lifetime by calculating the average time of the fluorescence electrical signal with respect to a predetermined apparatus delay time. According to the above configuration, the present invention can accurately and precisely measure a fluorescence lifetime in a short measurement time by easy calculation.

Apparatus for measuring fluorescence lifetime

The present invention relates to an apparatus for measuring a residual stress of an optical fiber. More particularly, the present invention relates to an apparatus for measuring residual stress of an optical fiber which is provided with a variable polarizer of which rotation is unnecessary instead of a rotary analyzer to measure the residual stress in high resolution and at high speed. There is provided an apparatus for measuring a residual stress of an optical fiber including a light generation unit that generates light; a lens unit that converts the generated light into collimated light; a polarization unit including variable polarization devices that divide the collimated light into two perpendicularly polarized light beams and control phase retardation of the polarized light beams by means of an electrical signal; a measurement unit that allows the divided light beams of two polarization states to penetrate an optical fiber to be measured; and a light detection unit that detects the polarization states of the light beams penetrating the optical fiber.

Apparatus for measuring residual stress of optical fiber

Disclosed is an apparatus and method for obtaining images using coherent anti-stokes Raman scattering. The apparatus for obtaining images using coherent anti-stokes Raman scattering according to the present invention comprises: a pump light source and a stokes light source that irradiate pump light and stokes light on a sample to generate anti-stokes light having anti-stokes frequency; a reference light source that generates reference light; and an image obtaining unit that obtains the images of the sample using a change in phase of the reference light due to a change in the refractive index of the sample in the vicinity of the anti-stokes frequency. Thereby, the present invention can provide the apparatus for obtaining images using coherent anti-stokes Raman scattering that is not affected by a non-resonant background signal phenomenon, strong resistance against noise even in a weak signal, and has excellent sensitivity and resolution.

Apparatus and method for obtaining images using coherent anti-stokes Raman scattering

An optical phase microscope using rotating-&#xbc; wavelength plate with pinhole in the center position and Fourier transformed lens is provided. The optical phase microscope comprises an optical image generator that acquires images for a specimen to be observed, an object plane onto which light beams of the images acquired from the optical image generator are projected, a first transform lens that performs primary Fourier transformation on the light beams passing through the object plane, a &#xbc; wavelength plate with pinhole at the center position that is positioned to be spaced by a focal distance of the first transform lens from the first transform lens, a secondary transform lens that performs secondary Fourier transformation on the light beams passing through the &#xbc; wavelength plate, and a phase image generator including a photo detector on which the images of the light beams subjected to the secondary Fourier transformation is focused.

Optical phase microscope using rotating 1/4 wavelength plate with pinhole in the center position and Fourier transformed lens

Disclosed herein is an apparatus for measuring the differential mode delay of multimode optical fiber. The apparatus includes a tunable laser source, an interferometer, a data collecting device, and a computer. The tunable laser source outputs light, frequencies of which vary linearly. The interferometer generates multimode light and single mode light by separating light, which is output from the tunable laser source, transmitting the multimode light and the single mode light to the multimode optical fiber, which is a measurement target, and a single mode path, which is a reference, and generating a beating signal by causing the multimode light and the single mode light to interfere with each other. The data collecting device collects the beating signal from the interferometer. The computer converts the frequency components of the beating signal into components in a time domain, and calculating the mode delay of the multimode light.

Growing community of inventors

Gwangju, South Korea

Dug Young Kim