Abstract:
PURPOSE: A polarization-maintaining optical fiber and a manufacturing method for the same are provided to use the cladding region by doping heterogeneous materials onto an optical fiber to form a silica layer. CONSTITUTION: An outer layer of a core is provided with a silica layer onto which heterogeneous materials whose thermal expansion coefficient and refractive index are reciprocal are doped. The heterogeneous materials are phosphorus and fluorine. An asymmetric induced residual stress generating region is formed by cutting both ends of a base material. A silica layer for use in a cladding region is formed on the both sides of the base material. Then, the base material is drawn with a desired strength. The base material is coated with a polymer.
Abstract:
PURPOSE: A polarization-maintaining optical fiber and a manufacturing method for the same are provided to use the cladding region by doping heterogeneous materials onto an optical fiber to form a silica layer. CONSTITUTION: An outer layer of a core is provided with a silica layer onto which heterogeneous materials whose thermal expansion coefficient and refractive index are reciprocal are doped. The heterogeneous materials are phosphorus and fluorine. An asymmetric induced residual stress generating region is formed by cutting both ends of a base material. A silica layer for use in a cladding region is formed on the both sides of the base material. Then, the base material is drawn with a desired strength. The base material is coated with a polymer.
Abstract:
PURPOSE: An apparatus for simultaneously measuring a refractive index and an absorption coefficient of material is provided to simply measure the refractive index and the absorption coefficient of material by using Fourier transform analysis. CONSTITUTION: A beam splitter(110) is provided to divide beam generated from a light source(100) into first and second beam paths having the same beam intensity. Beam passing through a material(120) positioned in the first beam path is reflected into a moving path by a first reflection mirror(130a). A second reflection mirror(130b) is provided to reflect beam into the moving path based on the second beam path. Beam reflected from the first and second reflection mirrors(130a,130b) is detected by a beam detector(140). A scan motor(150) is driven to scan a distance of an interferometer from the second reflection mirror(130b). A computer(160) analyzes a refractive index and an absorption coefficient of material to be measured.
Abstract:
PURPOSE: A mode filtering and selecting method at a multiple mode waveguide and a waveguide amplifier, a semiconductor laser and vcsel using the same are provided to enable a single mode to be guided with respect to a single direction by a filtering or selection rule obtained by changing a periodic refractive index at a clad portion of a waveguide. CONSTITUTION: A waveguide amplifier using mode filtering at a multiple mode waveguide is provided to enlarge a core size of a multiple waveguide consisting of a core(20) and a clad, and to enlarge a size of a mode field even at a single mode, in which light is passed at the single mode, by making a refractive index of a clad by a refractive index structure of the clad have a higher refractive index(22) only at the single mode.
Abstract:
PURPOSE: A device for measuring fine distance using an optical fiber interferometer is provided to reduce measurement error caused by changing a path of interferometer due to change of air flow, temperature and pressure or external vibration. CONSTITUTION: A device for measuring fine distance using the optical fiber interferometer includes a laser light source(210), an optical fiber coupler(230) coupling light emitted from the light source, dividing into lights of the same intensity, transferring to a measuring path and a standard path and coupling reflected light, an optical fiber mirror(250) disposed on the standard path for reflecting light transferred from the optical fiber coupler, an optical fiber polarizing adjustor(240) disposed on the standard path, an optical fiber collimater(260) aligning light transferred from the optical fiber coupler, transferring in a straight line and reflecting reflected light to the optical fiber coupler, a mirror(270) reflecting light transferred from the optical fiber collimater in straight line to the optical fiber collimater, an optical detector(280) for detecting intensity of interference pattern by light generated during the coupling process, and a microprocessor(290) calculating phase of interference pattern in a real time and displaying.
Abstract:
본 발명은 광 미세거리 측정기술과 푸리에 분광법을 이용하여 짧은 길이의 광섬유에 대한 색분산을 정밀하게 측정할 수 있는 광섬유의 색분산 측정장치에 관한 것으로, 이를 위하여 본 발명에 따른 광섬유 색분산 측정장치는, 광섬유의 색분산을 측정하기 위해 LED 광원을 이용하여 광신호를 발생하고 이를 공기 중으로 전송하며, 공기 중으로 전송된 광신호를 다시 광섬유 내로 투과시켜 광신호의 세기에 따른 간섭무늬 데이터를 측정하는 제 1 간섭계 및; 헬륨-네온 광원을 이용하여 공기의 흐름에 따라 변화되는 간섭무늬의 스캐닝 포지션을 검출하여 광섬유의 미세거리에 따른 간섭무늬 데이터를 측정하는 제 2 간섭계; 그리고 제 1 간섭계로부터의 데이터를 푸리에 변환하여 파장에 따른 광섬유의 굴절률의 차를 산출하고, 산출된 굴절률을 파장에 대하여 미분하여 광섬유의 색분산을 산출하는 컴퓨터를 포함하는 광섬유의 색분산 측정장치를 제공함으로써, 종래의 광섬유 분산 측정장치에 비하여 간단한 광섬유의 색분산 측정 방법을 이용하여 1m 정도의 짧은 길이의 광섬유의 분산값을 매우 정밀하게 측정할 수 있게 됨으로서 측정하고자 하는 파장에서 흡수나 손실계수가 큰 경우에도 정확한 색분산을 측정할 수 있는 효과가 있다.
Abstract:
PURPOSE: An apparatus for automatically sustaining a focus of a laser light is provided to be very stable of an external impact and a vibration by producing automatically a focus distance of a light lens. CONSTITUTION: Two lasers(21,23) irradiate lights(B1,B2) having a different wavelength to each other. The lights from the laser(21,23) are respectively provided to an optical fiber(31) having a 50-to-50 optical fiber coupler(25,27) and a WDM(wavelength division multiplex) coupler(29). The laser lights(B1,B2) passing through the WDM coupler(29) are provided to one end of a WDM coupler(33) and a light(B3) from a laser(35) is provided to the other end of the WDM coupler(33). The lights(B1,B2,B3) through the WDM coupler(33) are diffused through the end of the optical fiber(31). The diffused lights are collimated through an optical lens(37) and form a focus at a distance different with lights(B1,B2,B3) wavelength. The lights(B1,B2,B3) passing through the light lens(37) are reflected from a reflection face(39) and then again are induced to the optical fiber(31) through the optical lens(37). The reflected lights(B1,B2) are provided to the optical fiber(31) through the WDM(29,33), the reflected light(B1) is provided to the coupler(25), and the reflected light(B2) is provided to the coupler(27). The reflected light(B1) passing through the coupler(25) is provided to an optical detector(41) and the reflected light(B2) is provided to an optical detector(43). The optical detectors(41,43) output a voltage corresponding to the strength of the reflected lights(B1,B2).
Abstract:
PURPOSE: An apparatus and a method for measuring the thickness of a material using focal length of an optical fiber lens is provided to measure the thickness of a material having a multi-layered structure by using a fact that lights passed through the optical fiber lens are different in amount of lights reflected from a surface of the material. CONSTITUTION: A PZT(Piezo Electric Transducer)(12) moves vertically to a material to be measured in thickness. An optical fiber lens(10) is attached to the PZT for outputting Gaussian beam. A laser(14) generates light source. A light separator(16) prevents light output from returning. A 3dB optical fiber coupler(18) separates light strength output from the optical fiber lens and the laser in a ratio of 50:50. An optical detector(20) detects strength of the light reflected to an end of the optical fiber lens. An RC filter(22) filters the detected light. A micro processor(24) analyzes strength of the detected light. An amplifier(26) amplifies strength of an electric signal according to control of the micro processor. A PZT driving unit(28) drives the PZT according to the strength of the electricity amplified from the amplifier. An X-Y axis scanner driving unit(30) drives X and Y axis scanners according to the control of the micro processor. An X axis scanner(32) is for driving an X-axis according to the driving of the X-Y axis scanner driving unit. A Y-axis scanner(34) is for driving a Y axis according to the driving of the X-Y axis scanner driving unit.
Abstract:
본 발명은 자동 거리 유지장치를 이용한 물질 표면구조 측정장치에 관한 것으로, 서로 다른 파장을 갖는 제 1 및 제 2광원을 하나의 전송로에 다중 유도하는 파장분할 다중화수단과, 상기 다중 유도된 제 1 및 제 2광원을 특정 물질의 표면 방향(Z축 방향)으로 집중시키는 집광수단과, 상기 물질 표면이 상기 제 1광원의 광웨이스트와 상기 제 2광원의 광웨이스트 사이의 소정 위치를 유지하도록 제어하는 서보수단과, 상기 물질 표면을 X축 및 Y축 방향으로 측정하는 스캔수단과, 상기 서보수단에 의한 위치 제어값을 상기 물질 표면의 Z축 좌표로 입력받고 상기 스캔수단에 의하여 측정된 상기 물질 표면의 X축 및 Y축 좌표를 입력받아 상기 물질 표면구조를 3차원 정보로 가공하는 이미지 처리수단을 포함하여, 종래 기술과 비교할 때에 위상 측정장치 및 광분 리기 등과 같은 광학계가 사용되지 않아 안정된 구조를 가지며 구조가 간단하여 외부 충격에 매우 강한 이점이 있다.
Abstract:
본 발명은 레이저 광의 초점을 자동으로 유지시키는 장치에 관한 것으로서, 본 발명은 서로 상이한 파장을 갖는 제 1 및 제 2 광원과; 반사면과; 제 1 및 제 2 광원으로부터의 광을 상기 반사면에 투사하는 렌즈와; 반사면으로부터 반사된 제 1 및 제 2 광원의 광을 렌즈를 통하여 수신하고, 수신된 제 1 및 제 2 광원의 광들간의 세기 차이에 대응하여 렌즈의 초점을 조정하는 수단을 구비한다. 즉, 본 발명에서는 서로 다른 파장을 갖는 두 개의 레이저 광에 의해서 각기 형성되는 광웨이스트의 위치를 검출하고, 이 광웨이스트에 대응하여 광렌즈의 초점 거리를 자동으로 산출하므로써 외부의 충격이나 진동에 매우 안정적이며, 동일한 초점 거리 특성을 갖는 장치를 대량 생산할 수 있다는 효과가 있다.