Abstract:
PURPOSE: An optical fiber laser resonator is provided, which is used as a pumping source of a Tm-doped fiber amplifier of a non-silica family. CONSTITUTION: The first optical fiber(20) is connected to a laser diode(10) by a pig tailed form, and the second optical fiber(40) is connected by a different structure from the first optical fiber. The third optical fiber(31) consists of a cladding(42) and a core(41) where a grating is engraved and is configured to connect both ends of the first and second optical fibers by a tapering method. The first optical fiber is an SMA cable, the second optical fiber is a dual clad fiber which consists of a Yb-doped core and a cladding. GeO2 is doped in a core where the grating of the third optical fiber is engraved. A silica(32) as a packing means is configured such that an air gap is formed at the outside of the third optical fiber so that light passing through the cladding of the third optical fiber progresses smoothly.
Abstract:
PURPOSE: A method is provided to control an optical waveguide size stably by adopting an active ion etching process using an ion exchange process and a photolithography process, and to achieve a steep stair-shaped wall and a constant depth irrespective of a pattern width. CONSTITUTION: A surface portion is formed on a glass substrate having a refractive index of 1.45 to 1.60. A refractive index of the surface portion is larger than that of the glass substrate. A photoresist pattern is formed on a position where a waveguide is formed. An optical waveguide(12) is formed by etching the surface portion of the glass substrate through an active ion etching process using the photoresist pattern as a mask. After removing the photoresist pattern, a cladding layer(13) is formed by coating a material having a lower refractive index than the glass substrate on a resultant structure.
Abstract:
PURPOSE: A non-contact coupling type binary phase hologram and a method for realizing the same are provided to realize the coupling type binary phase hologram without physically contacting two holograms to each other, thereby preventing the deformation of the holograms due to the wear of the hologram surfaces. CONSTITUTION: A non-contact coupling type binary phase hologram includes a main hologram(510) for diffracting light emitted from a laser, an auxiliary hologram(520) apart from the main hologram by a predetermined distance not to contact the main hologram physically, and the predetermined number of lenses positioned between the main hologram and the auxiliary hologram, of which a first lens(530) carries out the high speed fourier conversion of a phase of the main hologram at a position apart from the main hologram by a predetermined distance, and a second lens(540) carries out fourier inverse conversion of the phase of the main hologram for restoring original phase and information at a position apart from the first lens by a predetermined distance.
Abstract:
이득을 크게하고 잡음지수를 낮추는데 적합한 2단 반사형 광섬유 증폭기에 관한 것으로, 이를 위한 본 발명은 파장분할다중결합기와 펌프광원으로 이루어진 광펌핑 장치, 및 신호광과 펌프광이 진행하는 이득광섬유를 포함하는 광증폭기에 있어서, 상기 이득 광섬유를 제 1 이득 광섬유와 제 2 이득 광섬유로 구분하는 광순환기; 및 상기 제 2 이득 광섬유의 끝단에 부착되어 상기 제 1 이득 광섬유와 제 2 이득 광섬유를 진행한 신호광과 펌프광을 반사시키는 거울을 포함하며, 상기 거울에서 반사된 상기 신호광과 펌프광이 상기 제 2 이득 광섬유만을 진행한 후 상기 광순환기의 한 단자를 통해 증폭된 신호광이 출력되는 것을 특징으로 하며, 광순환기의 위치를 바꾸고, 이득 광섬유의 길이를 변화시켜 증폭기의 이득 및 잡음지수를 조절한다.
Abstract:
PURPOSE: Provided is a clad mold for producing optical fiber by a melting method which can be prepared economically in a simple process, and thereby it is possible to prevent a parent material of optical fiber from being contaminated by impurities and deteriorated in its quality. CONSTITUTION: The mold of clad(10) for producing a parent material of optical fiber comprises a clad mold(11) of a pipe shape having an end closed, a predetermined length and an inner diameter corresponding to a diameter of a clad; and a cylindrical core rod(12) attached to the closed end of the clad mold(11) in the same axis as the clad mold(11) and having a predetermined length and an outer diameter corresponding to a diameter of a core to be formed. The clad mold is prepared by (i) pouring melted glass to a hollow of the mold of clad(10), followed by solidifying the glass to form a clad; (ii) removing the clad mold(11); (iii) removing the core rod(12); and (iv) inserting a core rod into a hollow formed by removing the core rod in the step (iii).
Abstract:
본 발명은 다파장 광섬유 라만 레이저의 구도에 관한 것으로서, 비선형 광학 매질로서 펌프 광원에 대한 라만 산란을 유발시키는 광섬유와, 상기 광섬유의 라만 이득 파장 범위 내에서, 각기 다른 파장에 대한 선택적 반사 특성을 지닌 다수의 광섬유 회절격자 쌍을 이용한 공진기로 구성된다. 공진기를 구성하는 회절격자 쌍의 파장에 따른 반사 특성을 개별적으로 조절함으로써 발진하는 파장과 그 세기를 독립적으로 제어할 수 있다. 본 발명의 실시예로서 2차 스톡 주파수 천이된 두개의 파장들을 발진시키는 캐스캐이드 광섬유 라만 레이저를 제공한다. 본 실시 예에서 펌프 광원으로 1313 ㎚의 Nd:YLF 레이저를 사용하여, 1480 nm 와 1500 nm 에서 발진하는 라만 레이저를 구현하였다. 이와 같은 레이저는 광 증폭기의 펌프 광원으로 사용될 경우 증폭기의 이득 파장 영역을 확장시킴과 동시에 이득 평탄화를 능동적으로 구현 할 수 있다는 장점이 있다
Abstract:
PURPOSE: An optical wave guide, in which rare earth ion is added, is provided to transform an amplified spontaneous emission spectrum with transition of erbium from ¬4I13/2 to ¬4I15/2 for making the gain in a shorter wavelength than 1530mm. CONSTITUTION: The optical wave guide, in which rare earth ion is added, includes a core and a clad. The core is a central layer and the light is transmitted from the core. The clad makes that the light doesn't escape to the outside. The erbium(Er) ion is doped in the appointed distance of the central point of the core. The rare earth ion is doped on the inside or the surface of the core distant from the central point of the core. The rare earth ion is dysprosium(Dy), thulium(Tm), terbium(Tb) or neodymium(Nd) ion. The range of the distance between the erbium doping field and the rare earth doping field is to a semi-diameter of the core from 20mm.
Abstract:
PURPOSE: A device of stabilizing a mode-locked optic-fiber laser is provided to stabilize the length of the optic-fiber laser oscillator and feedback optical light into the laser oscillator to minimize error after detecting the reflected signal from an optic-fiber loop mirror. CONSTITUTION: In a device of stabilizing a mode-locked optic-fiber laser, a pump laser(101) pumps optically gain medium. An optic-fiber(102) includes Er to make a non-linear effect. A polarization maintenance single mode optic-fiber(104) is used to boost non-linear quality. A PZT device(106) compensates the length of a laser oscillator by feedbacking optical light. A photo modulator(107) realizes an active mode-locking by modulating the loss or phase of the oscillator with a set frequency. A photo isolator(108) sends light in one direction. A ten percent photo coupler(109) monitors laser output. The device also includes a non-linear amplitude loop mirror(103), a fifty percent photo coupler(105), a photo diode(110), a circuit block and a linear loop mirror(120).