Abstract:
The present invention relates to a method of manufacturing a waveguide using an ion exchange process. The present invention controls the refractive index and the thickness of a surface layer on a glass substrate using an ion exchange process, forms the waveguide pattern on the surface layer by means of photolithography and etching process and coats with materials having the refractive index same to or lower than that of the glass substrate to form a cladding layer. Accordingly, the present invention can manufacture a planar waveguide, which is excellent in dimension control and reproducibility and has a sharp step wall.
Abstract:
The present invention relates to a multi-layer optical planar waveguide which is vertically coupled using multimode-interference couplers and to the method of manufacturing the same. The purpose of this invention is to increase the degree of integration on the multi-layer optical planar waveguide by applying the concept of via holes of the multi-layer printed circuit board (MLPCB) used in electronic circuits to the optical waveguide devices. According to the present invention, particularly, a multimode interference coupler of a stepped structure has the higher coupling ratio at relatively short length of interference than the usual multimode interference coupler. The present invention can implement a multimode interference coupler at a specialized spot while reducing evanescent field interference between the upper and lower optical waveguides out of the spot by separating the layers enough.
Abstract:
A high-speed wavelength channel selector has properties of relatively easy manufacturing and easy extension to multi-channel integration, and a high-speed space and wavelength multiplexed channel selector uses the high-speed wavelength channel selector. The high-speed wavelength channel selector is integrated with electro-optic waveguide switches of non-crystalline materials, such as electro-optic polymers or glasses, in the middle of a pair of wavelength multiplexer and demultiplexer and the high-speed space and wavelength multiplexed channel selector has the photonic integrated circuit-type composition of a space multiplexed channel selector containing M electro-optic waveguide switches and an M×1 channel combiner, the high-speed wavelength channel selector, optical amplifier and a high-speed wavelength converter.
Abstract:
A planar waveguide-type optical amplifier switch is disclosed. The switch is developed with the purpose of solving the problems that the conventional waveguide-type optical switch, which has been being used in the optical communication technique, has an optical loss and thereby requires an external optical amplifier which makes the whole devices not suitable for forming an integrated compact device. The disclosed switch performs switching function from the refractive index change in the optical waveguides induced by electrical or optical controls as well as amplifying function of the optical signal, when it passes through the waveguides, from use of optical waveguides formed of a fluorescence emitting material with an optical pumping and a wavelength division multiplexing (WDM) optical waveguide-type coupler. The optical amplifier switch scheme, which provides a simultaneous optical switching and amplification in an optical waveguide form, allows the device fabricable in a compact integrated manner and more useful in practical applications. The optical amplifier switch in accordance with the present invention can replace the conventional optical switches of the prior art, and can promote technical development in the areas of high-capacity optical communication systems, massive optical signal processing, optical switching, optical computing, and so on.
Abstract:
The present invention discloses an all-optical wavelength converter using a semiconductor optical amplifier and a polarization interferometer. The all-optical wavelength converter using a semiconductor optical amplifier and a polarization interferometer including a wavelength converter which modulates a probe light into a inverting waveform to a signal light and outputs the modulated light by using cross gain modulation, a phenomenon that occurs while the signal light and the probe light pass together through an optical splitter/combiner, a semiconductor optical amplifier and a filter at the same time, a polarization interferometer which makes the probe light outputted from the wavelength converter and having the inverting waveform to the signal light undergo a double-refraction so that a predetermined time split occurs on it and provides a non-inverting wavelength conversion and suppresses the slow XGM components in the converted outputs due to the slow carrier recombination time.
Abstract:
An optical fiber Mach-Zehnder interferometer optical filter is disclosed. The filter includes a stabilization light source for varying a first wavelength of a light signal for stabilizing a Mach-Zehnder interferometer, first and second optical fiber couplers for receiving an optical signal from the stabilization light source and an optical signal of a second wavelength different from a first wavelength inputted from an input port and dividing into two parts having the same intensity for thereby forming a Mach-Zehnder interferometer, a polarization controller connected with one side of the first optical fiber coupler for controlling a polarization of the interfered light of the interferometer, first and second wavelength division multiplex optical couplers connected with the second optical fiber coupler for separately outputting a first wavelength optical signal and a second wavelength optical signal, an optical fiber phase modulator connected with the other side of the first optical fiber coupler for varying the length of the optical fiber in accordance with a fed-back phase difference, and a stabilization circuit for receiving two optical signals of the first wavelength from the first and second wavelength division multiplex optical couplers and feeding back the phase difference to the optical fiber phase modulator for thereby implementing a constant optical path difference of the interferometer.
Abstract:
There is disclosed a mode-locked optical fiber laser stabilizing apparatus for stabilizing the length of the optical fiber laser resonator by feedbacking the optical signals to the laser resonator, in the direction where the signal reflected by the optical fiber loop mirror is detected as an error signal to minimize the signal, and method thereof. According to the present invention, a resonator stabilizing apparatus in an optical fiber laser includes a non-linear optical amplitude loop mirror (NALM) for non-linearly amplifying a laser pumped laser light, a linear loop mirror of a closed loop shape for confining the laser light sufficiently amplified by the non-linear optical amplitude loop mirror; a light isolator for proceeding the light confined by said linear loop mirror only in one direction, an optical coupler for detecting the light proceeding in the direction opposite to the light isolator by the linear loop mirror, the phase of which is varied in the non-linear optical amplitude loop mirror, and a piezo-electric transducer (PZT) for performing a signal processing for minimizing the amount of light proceeding in an opposite direction when the light detector detects the light proceeding in the opposite direction and feedbacking again the light to stabilize the light, the light detector is coupled by the linear loop mirror and the optical coupler.
Abstract:
An apparatus for measurement of an optical pulse shape intended to measure the temporal waveform of an ultrashort single optical pulse is disclosed. The present invention comprises a linearly chirped supercontinuum light source that is synchronized with an optical pulse to be measured; a nonlinear optical interferometer to transform the temporal waveform of an incident optical pulse into a spectrum using an incident light from said supercontinuum light source; and an optical spectrum analyzer to measure the wavelength of the light passing through the nonlinear interferometer so that it can measure the temporal waveform of a single optical pulse. The present invention employs the method that transforms the temporal waveform of an incident optical pulse into a spectrum and measures the wavelength using a linearly chirped supercontinuum light source, a nonlinear optical interferometer, and an optical spectrum analyzer. The present invention provides an apparatus for measurement of an optical pulse shape that is able to measure the waveform not with the repeated measurements but with a single shot measurement.
Abstract:
Provided is a polymeric optical device comprising a substrate, a lower cladding layer formed on the substrate, at least one core layer pattern formed on a predetermined region of the lower cladding layer and an upper cladding layer having at least two sub-upper cladding layers and formed on the lower cladding layer in which the core layer pattern is formed, and a method of fabricating the same, whereby birefringence of a polymeric optical device could be improved and polarization dependence could be reduced by adjusting the thickness of the sub-upper cladding layer and the number of stacks thereof.
Abstract:
A laser structure for obtaining an optical pulse of a very short duration by using the benefit of a passive mode locking and for improving a repetition rate of an output optical pulse was described. In general, a passively mode-locked laser generates a short optical pulse than a active mode locked laser does, while it has difficulties in increasing the repetition rate of the output optical pulse because the repetition rate of the passively mode-locked laser is determined by the length of the resonator. In accordance with the present invention, a delayed optical path is added to the linear loop of a conventional figure-8 optical fiber laser. The propagation time difference .DELTA.T between the delayed optical path and undelayed short optical path is adjusted to a divisor of the round trip time, T, of the original resonator by properly adjusting the length of the delayed optical path. Thus, the repetition rate of the output optical pulse of the mode locked laser can be increased from 1/T Hz to 1/.DELTA.T Hz. The optical fiber laser which can fully exploit the advantages of the passive mode locking and improve the repetition rate of the output optical pulse in accordance with the present invention can be applied to a wide range of applications including an optical communication and an ultra high speed analysis of optical phenomena.
Abstract translation:描述了通过利用被动模式锁定和改善输出光脉冲的重复率来获得非常短持续时间的光脉冲的激光结构。 通常,被动锁模激光器产生比有源模式锁定激光器短的光脉冲,而由于被动锁模激光器的重复频率由被动锁模激光器的重复频率确定,所以难以增加输出光脉冲的重复率 谐振器的长度。 根据本发明,将延迟的光路添加到常规的图8的光纤激光器的线性环路中。 延迟光路和未延迟的短光路之间的传播时间差DELTA T通过适当地调节延迟光路的长度来调整到原始谐振器的往返时间T的除数。 因此,锁模激光器的输出光脉冲的重复率可以从1 / T Hz增加到1 / DELTA T Hz。 可以充分利用被动模式锁定的优点并提高根据本发明的输出光脉冲的重复率的光纤激光器可以应用于广泛的应用,包括光通信和超高速分析 的光学现象。