This PDF file contains the front matter associated with SPIE Proceedings volume 7509, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing.

A new encoder-decoder scheme of OCDMA using electro optic crystal is proposed, which is suitable for 1-D time spread and 2-D wavelength/time spread system. The electro-optic deflector and switch is made by electro optic crystals and each part of this system is analyzed. A simulation was made for OOC with this new encoder-decoder scheme, and the result showed that this technique was effective. It will play an important role in all-optical netwoks with its simple scheme, flexible control and convenient upgrade.

A large size RGB LED backlight unit and its local dimming algorithm are presented in this paper. The LED backlight unit and the LCD panel are controlled synchronously to enhance image contrast and improve power efficacy. Based on the image content, the backlight intensity is locally dimmed, and pixel values are compensated according to the backlight brightness distribution. In addition, a linear function algorithm typical for a backlight system is applied to remove the grid artifacts between LED blocks. Our newly developed 32" RGB LED backlight LCD-TV prototype shows that a static display contrast of over 20000:1 can be achieved. Compared with CCFL backlight LCD-TV, an average of about 30% of the power can be saved depending on the image content.

We firstly propose the technique to realize far-filed image by integrating the microlenses array with LCD. This technique is expected to resolve eye-gazing problem in common teleconferencing system without affecting the display performance of LCD. The characteristics of far-field diffraction image and geometric image formed by single microlens are simulated and analyzed. The simulation shows that the quality of image is seriously reduced by geometric aberration and diffraction of the small aperture diameter for aspherical and spherical surface profile refractive microlens. The main problem of image acquisition with high resolution is that the signal obtained by cell detector is contributed not only by the sampling point in the axis of the corresponding cell microlens but also sampling points nearby. In simulation, Microlenses of 300μm diameter same with pixel size of LCD were used in orthogonal array at 1mm pitch, which is also the sampling interval in object space. These microlenses array with unit number 213x246 are placed up to 600mm away from object surface. Monte Carlo optimization algorithm is adopted to give accurate inversion results. The typical results are presented with our main conclusions.

In this paper, we investigated in detail the characteristics of slanted multimode fiber Bragg gratings (MFBGs) both theoretically and experimentally. Our analysis clearly revealed the significant effect of slanted angels on the transmission spectra and the characteristics of MFBGs. On a 2° slanted MFBG, both experimental and theoretical results showed that the strain and temperature sensitivities were almost the same for different transmission dips. Utilizing this property, switchable and tunable multi-wavelength fiber ring lasers were realized. The configurations were simple and multipurpose. Our results showed that the lasers can generate single-, dual-, three-, four-, and five- wavelength lasing; and a 4.2 nm continuous wavelength tuning range was achieved. On a 3° slanted MFBG, a novel and simple sensor was developed for simultaneous temperature and refractive index measurement. The 3° slanted MFBG showed two wavelength groups in its transmission spectrum: one group, due to the coupling from one core mode to cladding modes, was sensitive to both surrounding refractive index (SRI) and temperature, and, the other, due to the coupling from one core mode to other core modes, was sensitive only to temperature. Utilizing this property, two parameters can be distinguished and measured simultaneously using one slanted MFBG.

The analytical expression of transmittivity and reflectivity of dual fiber Bragg grating (FBG) and the gain equations of the laser are obtained by the coupled mode theory. The laser gain curve is studied through the length of dual FBG and optical fiber length between two gratings under coherence collapse. The relative parameters have been optimized to get the best mode-stabilizing characteristics. The output spectral characteristics and the output power of the laser with dual FBG are practically measured. At the temperature of 0°C~70°C, the wavelength shift is 0.5nm. The side mode suppression ratio (SMSR) is more than 45dB. The Full Width at Half Maximum (FWHM) is less than 1nm.

Resonant wavelength and wavelength spacing tunable dual-channel fiber Bragg gratings based on filling functional material into highly birefringent photonic crystal fibers is proposed and investigated. The tuning properties of the resonance wavelength of Bragg gratings depended on altering the liquid indices filled in the holes of PCF are theoretically investigated. It is demonstrated that the resonant wavelengths are tuned as wide as 40 nm with a slope of 80 nm per refractive index unit (RIU), and wavelength spacing as large as 5 nm with a slope of approximate 12 nm/RIU corresponding to the two orthogonal polarization states.

We present the following novel technologies for optical coherence tomography developed in Institute for Microstructural Sciences, National Research Council Canada. We first demonstrate a high power mode-lock wavelength swept laser using a polygon-based narrowband optical scanning filter first. Peak and average output powers of 98 mW and 71 mW have been achieved, respectively, without an external amplifier, while the wavelength was swept continuously from 1247 nm to 1360 nm. Then, we present a design, construction and characterization of ultra-small OCT probes using fiber lenses. Those fiber lens modules are made of a single mode fiber and a GRIN or ball fiber lens with or without a fiber spacer between them. The lens diameters are smaller than 0.3 mm. We discuss theoretical models, design methods, fabrication techniques, and measured performance compared with modeling results. Finally, we demonstrate an instantaneous complex conjugate resolved swept-source OCT using a 3x3 Mach-Zehnder interferometer. The interferometer provides simultaneous access to complementary phase components of the complex interferometric signals; therefore, the effective imaging depth was doubled. The complex conjugate artifact suppression of 27 dB was obtained. OCT Images of human nail and animal tissue are presented.

Reconfigurable optical add/drop multiplexer (OADM), which is the fundamental element of wavelength division multiplexing (DWDM) system, employs various waveguide filter approaches. However, most of them are incapable of dropping more than a single channel at one time. Therefore, an electro-optically tunable reconfigurable OADM with Ti: LiNbO₃ waveguide was designed and analyzed. The two electrodes layers, separated by silicon dioxide buffer, applied two orthogonal electrodes fields in the waveguides which induced the wavelength dependent polarization conversion and phase shifted respectively, and hence realized the add or drop function combining with two identical polarization beam splitter waveguides. Profiting from the two layered electrodes structure, the tuning range was enlarged twice as the original filter design. The multiple channels download is feasible due to the novel structure of the polarization conversion electrodes.

In this paper a silicon-based digital optical switch (DOS) with the slot structure is demonstrated. By filling electro-optic polymer in the void slot of the branches, the electro-optic effect can be applied to the DOS, and a high-speed silicon switch with digital switching property can be achieved. Analysis shows that the crosstalk is about 35dB, switching speed is less than 1ps, and the device length is less than 1mm.

In this paper, an all fiber high-speed magneto-optic switch based on Faraday rotation in Bismuth-substituted Rare-earth Iron Garnet single crystal is proposed and investigated. It contains optical route, picosecond pulse generator and high-speed magnetic field structure. The optical route is designed with the function of switching the output optical signals in the networks. The biasing circuit for the magnetic field should be able to change the voltage rapidly in order to obtain fast operating time of the magneto-optic switch. Therefore, a kind of picosecond pulse generator based on the low-voltage avalanche characteristics of RF-BJT BFP450 is designed to drive a high-speed magnetic field. The experimental results indicate that the rise time of the output current pulse is only hundreds of picoseconds, which is satisfying for the high-speed magneto-optic switch. A current solenoid is used as high-speed magnetic field structure in this paper. It is noted that there is a time constant associated with the inductance of the current solenoid, which is an important factor determining the switching time. The switching time of the device also depends on the switching of the magnetic domains in the magneto-optic material. By controlling the magnetization of the magneto-optic material, the optical beam can be stably switched. The measured switching time of the device is only 134.2ns, so it can be widely used in the all-optical communication networks.

In this paper, an adiabatic soliton compression (ASC) compressor using a loss management fiber link (LMFL) comprised of alternating erbium-doped fiber (EDF) and ordinary single-mode fiber (SMF) is proposed. The EDF provides quasi-distributed gain instead of distributed gain provided by Raman amplification along the fiber link to compensate the fiber loss. With appropriate choice of length, segments numbers of erbium fiber and pump power, ASC will be realized. The input optical pulse will get narrower through adiabatic soliton compression effect when it propagates in the LMFL. Numerical simulation shows that a fundamental soliton pulse with repetition rate, width and peak power of 40GHz, 10ps and 478mW, respectively, can be compressed to a 1.40ps-width pulse with small pedestal by using the LMFL. The main advantages of this method are as follows: Firstly, by changing the pump power of EDF, the compressed optical pulses with different compression factor can be obtained. Secondly, compared with other adiabatic soliton compression techniques based on Raman amplification, dispersion-decreasing fiber or comb-like dispersion profiled fiber, this method is easy to control and costs less.

In this paper, we propose an all optical OTDM demultiplexer basing on a novel Mach-Zehnder interferometer. The principle for demultiplexing is similar to the normal SOAs based MZI demultiplexer. Differing from the normal one, we creatively utilize a combination of fiber and space structure which is made by using thin membrane plating technology in GRIN lens, instead of the fused tapered fiber couplers of the general form. It has advantages of polarization insensitivity, broadband, high temperature stability. Utilizing this novel structure, 10Gbit/s tributary signal demultiplexed from 40Gbit/s signal is successfully demonstrated.

The geometry, electronic structures and conduction properties of V-doped anatase TiO₂ with O vacancy were investigated by using the plane-wave ultrasoft pseudopotential method based on the density functional theory(DFT). The calculated results show that the 3d state of V plays an important role in red-shift and the band gap will narrow after V doping in TiO₂. Furthermore, it was also found that a certain concentration of O vacancy in V-doped TiO₂ shows better electronic conductivity due to the increase of electronic concentration in the band gap. Our theoretical results are in good agreement with the experiment results.

A technique for morphology control of self-assembled organic films based on laser ablation is presented. The regioregular poly 3-hexylthiophene (RR-P3HT) films prepared by using drop casting method and spin coating method are irradiated and ablated by the ultraviolet KrF excimer laser. Absorption spectra and XRD profiles of the films are investigated. For spin coated films, Blue absorption spectral shift is observed; For drop cast films, Blue shift in the absorption spectra, accompanied with the disappearance of the peak intensity of XRD profiles, are observed. The results indicate that molecular structure has been changed due to photo-thermal effect and molecule cutting effect of laser ablation.

Researched the transmission spectral and delay characteristics of a kind of photonic crystal fiber Bragg grating. Firstly, we got the mode field and the effective indexes of the base mode by multipole method, then calculated the transmission spectrum of the fiber using the former data through couple-mode theory and transfer-matrix method, got the resonance wavelength and the reflectivity intensity. We also researched the apodization characters of this fiber grating, simulated the reflectivity spectrum and delay spectral of several different apodization functions, such as Gauss, super Gauss, cosine and parabola, got the optimal apodization function. We also compared the differences between conventional fiber grating and photonic crystal fiber grating on their reflection spectrum and delay, the structure influence of photonic crystal fiber was also discussed. It was found that the refractive index of core mode declined as wavelength rising, photonic crystal fiber grating had the similar transmission spectrum compared with conventional grating except the resonance wavelength showing a clear blue shift, cladding structure such as hole diameter, hole space changed the characters remarkably.

The key problems to be solved in stereo HMD (Head-Mounted Display) used in augmented reality are analyzed, such as brightness of image, fusion of virtual and real scene, binocular rivalry, occlusion, distortion, stereo vision and tracking of head and line of sight. An experimental platform of HMD is developed by discrete elements to research the key problems. The problem of fusion of virtual and real scene can be solved effectively by replacing the common beam splitter with polarization beam splitter in combiner. The variations of HMD vision effects including binocular rivalry with binocular overlapped range are investigated, and the results indicate that the optimal effect is achieved when the binocular overlapped range is 33~50% of the monocular field of view (FOV). At last, stereo vision is realized in HMD by the stereo image pairs made up according to the parallax theory.

The support device with 3-point are widely used in many kinds of support systems. However, some problems will emerge when the device is used in high precision system. For example, in the self-adaptive optical system, the different deformation of each support point will cause the dissimilar slope of the supported part of the system, will cause the position error of segment mirror. This paper, using elastic mechanics theory to calculate the elastic deformation, calculates the elasticity deformation of steel balls in the device; based on the principle of optical auto-collimation, tests the related deformations of the three support points under different normal loads; according to the calculation and the experimentation, compares and analyzes the results of calculation and experimentation, sums up the relationship between deformation and support sphere diameter and load value; lastly, proposes the principia to determine the diameter of the balls in high precision system, and provides reformative scheme to design a better support devices with 3-point. The results of this paper have been used in the design and development of self-adaptive optical system.

A wedge-shaped probe is developed and applied for the detection of transient electrical signals in an ultrafast scanning tunneling microscope measurement system. The probe is composed of a low- temperature grown GaAs photoconductive switch and a metal tip with a diameter of 5 micrometers. The designed probe functions as a sampler of transient signals generated by a sample of coplanar strip photoconductive switch with ultrafast optical pulses of 100 fs in the ultrafast measurement system. The shape of the probe makes the approach of the probe to the sample in a way that is much easier than the traditional rectangular one. The metal tip is attached to the coplanar strip transmission line integrated in the photoconductive switch. The design of the probe is presented and its performances have been reported in this paper. Photo of the wedge-shaped probe is given and transient signals in picoseconds were observed in contact mode with the developed wedge-shaped probe.

We present an investigation of spectral dynamics of an ultrashort-pulse Er-doped fiber laser mode-locked by a semiconductor saturable absorber mirror (SESAM). The SESAM used has a saturable absorption modulation depth of 18%, a saturation fluence of 70 μJ/cm² and a relaxation time of 10 ps at a wavelength of 1550 nm. Detailed pulse dynamics of the laser are measured at different pumping levels, and the laser operation is linked to the characteristics of the SESAM. It is observed that, as the pump power is increased, the laser operation changes from cw lasing, to self-Q switching, Q-switched mode-locking, and then cw mode-locking. Self-starting and stable mode-locking operation is achieved at a repetition rate of 12 MHz. The pulses with a width of 650 fs are produced at 1562-nm wavelength with a pump power of 80 mW, and the corresponding spectral width is about 5.0 nm (FWHM). Based on the complex Ginzburg-Landau equation, self-starting mode-locking process in the fiber laser is simulated, which confirms that ultrashort pulses can be achieved. The calculated spectral characteristics of the mode-locked pulses are consistent with the experimental observations.

We have demonstrated an all-fiber passively mode-locked ytterbium fiber laser operating with a rectangular spectrum profile. Mode-locking is achieved by adopting nonlinear polarization rotation (NPR) in an all fiber ring cavity with normal dispersion. The 3 dB bandwidth of the spectrum is 8.6 nm, the signal-to-noise ratio (SNR) is more than 40 dB, and the rising and falling band edges are very steep. The mode-locking pulse train is stable and has a repetition of 13.4 MHz. We believe that the laser is operating in the gain-guided soliton state, which means soliton formation is induced purely by the existence of gain and gain dispersion. This kind of mode-locked fiber laser with the rectangular spectrum has potential applications in optical-based ultra-high-speed signal collection system, optical frequency combs generation and supercontinuum light source.

We experimentally demonstrate coherent beam combination of two double-clad fiber lasers using mutual injectionlocking in an external cavity coupling structure. The configuration employs a corner cube as a mutual injection component to couple the two lasers. A beam splitter acts as the output coupler and far field intensity has been observed at the lens focus plane. We observe interferential fringes with the contrast ratio of 0.5, and a combination efficiency of 80% is achieved. The total output power exceeds 11 W. We present simulative discussion here on the influence of multitransversal modes of element beam. The multi-mode operation degrades the quality of the output beam of main peak power, fringe contrast ratio, and other parameters. The configuration has the potential to scale to more lasers without much structural modification.

Heavy Er³⁺-Yb³⁺-codoped fiber lasers can provide high gain laser emission, but the energy transfer and cumulative transfer processes between Er³⁺ and Yb³⁺ cannot be neglected. In this paper, the cumulative transfer and double-energy transfer processes are considered in the propagation equation and rate equation model. And we use this model to simulate the lasing operation of a short Er³⁺-Yb³⁺-codoped phosphate fiber laser. Then a 10.4 cm compact fiber laser with an output power of 170.4 mW, a bandwidth of 0.053 nm and a slope efficiency of 35.3% is demonstrated in experiment. The experimental results show that the theoretical model we used is more accurate than former models. Finally, the dependence of output power on output coupler reflectivity, active fiber length and Er³⁺-Yb³⁺ concentrations are investigated numerically. According to the simulation, when the pump power is less than 700 mW, Er³⁺ concentration of 1.0-1.2×10²⁶ ions/m³, Yb³⁺ concentration of 4.0-8.0×10²⁷ ions/m³, output coupler reflectivity of 0.7-0.8 and fiber length of 8-12 cm are desirable to optimize the performance of Er³⁺-Yb³⁺-codoped phosphate fiber laser. PACS 42.60.Pk; 42.55.Wd

This paper presents a theoretical analysis speckle effect and a comparison with experiment results on laser Doppler velocimeters at different velocity. We have found that the value of ratio between broadening of frequency and center frequency is about 30% from 32.2mm/s to 379.6mm/s and effect of speckle pattern is one of the prime reasons. The error caused by effect of speckle pattern is an intolerant value in velocity measurements.

Dispersion theory for refractive index and extinction coefficient of vanadium dioxide thin film is studied, and its temperature-dependence dispersion formula of optical constants is presented by numerical fitting with Sellmeier dispersion model. The optical transmittance and reflectance at different temperature and wavelength is calculated using film matrix theory. Vanadium dioxide thin films with different thickness are deposited by magnetron sputtering on glass, sapphire and silicon dioxide substrates, and the optical transmittance and reflectivity of the films are measured, and the experiment curve agrees well with that of simulation.

In this paper, an ultra-broadband all fiber light source for optical coherence tomography was obtained. This light source was obtained by supercontinuum (SC) generated in matched fibers with different characteristics. It was showed that the spectrum quality was affected by dispersion and nonlinear characteristics of the fiber pumped firstly. SC spectrum flatness on the short wavelength side of pumping wavelength was affected by characteristic of the fiber pumped secondly. Dispersion shifted fiber (DSF) was connected after highly nonlinear fiber (HNLF) to optimize spectral shape. Widely broadened SC spectrum was generated in the combination of 120m HNLF+4.5km DSF+2km single mode fiber (SMF) with 55 mW average pump power. 140.6nm 3 dB bandwidth spectrum on the short wavelength was obtained. About 4.1 μm longitudinal resolution could be obtained theoretically around ~1300nm by using this SC spectrum as the light source of optical coherence tomography system. A Fourier-domain OCT (FD-OCT) system was set up by using this light source. Dielectric film plane mirror, a three-layer microscope cover glass with 160 μm thick and onion scarfskin were used as test sample and their depth signal at one point was obtained respectively.

As LCDs are not self-luminance, a backlight unit (BLU) is necessary for LCDs. For a display installed on an airplane, the brightness of a BLU is required to be very high and the color temperature should be able to change to higher in order to guarantee the pilot can clearly and accurately read the information on the display. This paper presents a LED BLU consisting of high-luminous-efficiency white LEDs and blue LEDs. White LEDs with the luminous efficiency as high as 120lm/W provide the most of luminance. When an airplane flies to higher altitude, the pilot can push a button to lighten the blue LEDs to change the color temperature. The paper presents a theoretical model for luminous flux estimation. The simulation results show that the white-and-blue-LED-mixed BLU presents the merits of high brightness, various color temperatures, high uniformity, and less complicated control.

Coherently phased fiber arrays are being studied as a means of obtaining high-power high-radiance laser systems from a multitude of individual fiber emitters. A common maser oscillator is used to seed 7 fiber amplifiers in parallel. For coherent combining, optical phase-noise of amplifiers is a critical issue for obtaining good beam quality amplified laser. Experimental configuration of 7-beams ten-watt level fiber amplifiers is presented, and phase changes of combined beams are measured. It is found that phase noise at low frequencies is weakly dependent on the number of lasers while susceptible to pump current. This work paves the way towards designing such fiber optic phased arrays to very high power systems.

In this paper, a readout integrated circuit (ROIC) is presented for improving the operability of the LWIR arrays by using a super-pixel detector format scheme, identifying and deselecting the bad elements automatically. This ROIC features an input stage based on buffered direct injection (BDI) structure, which uses a differential stage to provide the inverting gain to improve linearity and to provide tight control of the detector bias. The threshold voltage of bad element de-selection is adjustable and the circuit could de-select the bad element automatically. The simulation result show that the bad sub-element de-selection precision is up to nearly 0.2nA when the threshold current is about 590.8nA. We analyze the errors affecting the precision and the calculated precision is 2nA. Finally, we discuss the bad sub-element de-selection precision in different integrating time.

Coherent beam combination (CBC) of laser array has the potential to solve the power limitation in single fiber laser as well as maintaining good beam quality. Fiber laser array in self-Fourier (S-F) cavity presents a promising approach for CBC due to its compactness, simplicity, ease of alignment, and stability in phase locking, which have been under intense research recently. In this paper, we perform a system level analysis on the fiber laser array in S-F cavity. Analytical analysis on the beam quality and power scalability will be presented. By numerical calculation it is found that the total power contained in the laser array has linear relationship with the laser numbers. The total output power P of N laser in a S-F cavity can be expressed as P ∝ 0.4× N. It is also revealed that power encircled in the diffraction-limited bucket will not increase with N, adding more laser elements in the laser cavity will result in more laser power contained in the sidelobes in the far-field pattern.

Coherent beam combination (CBC) of fiber lasers has the potential to solve the power limitation in single fiber as well as maintaining good beam quality, which have been under intense research recently. Considering the advantage of high diffraction efficiency, compact volume and relatively easy to fabricate, phase grating has been considered as a promising combination component, and has been under intensive research recently. In this manuscript, take sine phase grating as an example, the combination efficiency in the case of phase error, incident angle error and laser intensity fluctuations will be detailed. Conclusions can be obtained from numerical calculating that the effect of incidence angle error and intensity fluctuation can be controlled within the specified range using off-the-shelf techniques. Nevertheless, the question whether the phase error can be controlled to be within 0.32 rad when scaled to high power level remains open due to the limited control bandwidth of existing phase stabilization system. For practical engineering in CBC using phase gratings, phase error control is the key component towards high efficiency.

It is significant for the two freedom degree optical switch to study its mechanical characteristics and structural optimum design to improve its dynamic stiffness. Based on the finite element analysis and optimization calculation, a group of optimized structure parameters of optical switch is obtained. The validity simulation of the results is verified by the analyses of the random vibration, harmonic response and fatigue life. It proves that the optimization method adopted in this article is effective to improve the mechanical performance of the two freedom degree optical switch.

We present the design of a 2×2 photonic switch operating at 1.55-μm wavelength using electro-optic (EO) polymer waveguides. A Mach-Zehnder interferometer (MZI) is used to implement the proposed switch in which two identical 2×2 multimode interference (MMI) couplers are connected by two identical parallel single mode waveguides (two MZI arms). These two single-mode waveguides with electrodes allow modulating the phase difference between the two MZI arms based on the EO effect. In the proposed switch, the EO polymer, IPC-E/polysulfone, is used for the core layer of optical waveguides. UV15 and NOA61 are employed for the lower and upper cladding layers, respectively. The singlemode waveguide structure and 2×2 MMI coupler have been designed and analyzed for the EO switch. Device performance has been simulated using the beam propagation method. It is found that the switch performance is most sensitive to the MMI width and less sensitive to the MMI length. Optimized structure has been obtained for the 2×2 polymeric EO switch, which has a crosstalk level better than -25 dB and insertion loss lower than -1.8 dB. This performance makes the switch a potential candidate for practical use in photonic systems.

Supercontinuum(SC) source has found numerous applications, such as DWDM, frequency metrology, optical coherence tomography, and optical measurement. We demonstrate an all-fiber supercontimuun source generated in highly nonlinear fiber (HNLF). The HNLF is pumped by our mode-locked fiber laser with pulse width and peak power, 21.1ps and kW, respectively. An ultra-broadband supercontinuum extends from 1000 nm to 1750 nm is obtained, and the spectrum is flat with the amplitude variation less than 4dB except around the fiber zero dispersion wavelength. The spectrum of our supercontinuum source can extend beyond 1750 nm, but due to the limitation of the measured range of optical spectrum analyzer (AQ6317B), the spectrum of the supercontinuum source beyond 1750 nm is not yet obtained in our lab now. The spectral broadening mechanism of smoothed supercontinnum is considered by the higher-order soliton fission and their blue-shifted dispersive wave.

The transmission of normally incident plane wave through periodic subwavelength metallic slits with perpendicular waveguides has been explored. Two-dimensional electromagnetic fields around the slit with waveguide are simulated by the finite-difference time-domain method. Especially, the influence of the waveguide width on transmission is studied.

A monolithic optical receiver fabricated in standard 0.5μm CMOS process is presented. The fingered doublephotodetector with structure of P+/N-well and N-well/P-substrate is designed. Some critical characteristics of doublephotodetector are analyzed in detail. At 2.5V reverse voltage, the maximum dark current is 10 pA. The intrinsic cut-off frequency is above 100MHz. The measured and simulated responsivity is 0.04A/W and 0.03A/W at 850nm wavelength, respectively. In the testing of double-photodetector, the minimum and maximum of rise time is 2.67ns and 7.11ns while the minimum and maximum of fall time is 2.67ns and 31.78ns. A Spice model of DPD is established for the compatibledesign of OEIC. In simulation of pre-amplifier circuit, the pass-band gain is approximate 18.8 KΩ. The lower cut-off frequency is 7KHz while the upper cut-off frequency is 700MHz. The simulated eye diagram of OEIC at 100Mbps is featured of clear trace, wide eye-opening and small zero-crossing distortion. The small signal bandwidth of OEIC is about 54MHz. The eye diagram at 50Mbps and 250Mbps has some distortion due to direct current malajustment. In the point-to-point optical interconnection, the transmission bit rate of 72Mbps is achieved. The monolithic optical receiver can be applied in 10M/100Mbps optical data transmission.

A new design of monolithic optical receiver at 850nm for fiber transmission is discussed in this paper. A Spatially Modulated (SM) photodetector and a pre-amplifier are integrated in the optical receiver chip. Some critical parameters of SM photodetector, such as responsivity in different regions, are calculated, and its structure is optimized to get the typical size. And then a novel Spice model of SM photodetector is accomplished in SPECTRE environment based on the numerical calculations above. The simulation results show that the bandwidth and responsivity can reach to 400MHz and 62mA/W at 850nm wavelength. The monolithic optical receiver, including SM photodetector and pre-amplifier with cutoff frequency 780MHz, was successfully fabricated in 0.5μm standard CMOS technology. The transmission rate is 100Mbps by replacing the commercial 100Mbps optical transceiver product. It is expected to be more than 100Mbps if 1000Mbps transceivers are used in test. The experiment and simulation results indicate that the monolithic optical receiver can be applied to 10M/100Mbps fiber transmission.

Sol-gel-processed silica films doped with Disperse red 1 (DR1) as well as sol-gel-processed DR1/TiO₂/SiO₂ films are prepared. The reaction process of sol-gel system is discussed theoretically. The optimal preparation for the dye-doped silica film is investigated as well. The content of catalyzer and the various mol ratio of raw materials in starting solution have influence on the electro-optic performance of the hybrid films. The film was spin-coated on the ITO coated glass substrate and rapidly condensed by evaporation of the solvent. Disperse red 1 (DR1) are doped in the three-dimensional silicon dioxide/titanium dioxide network possessing a high electro-optic coefficient r₃₃. The EO coefficients of the poled DR1/SiO₂ films and the poled DR1/TiO₂/SiO₂ films achieved 65 pm/V and 72 pm/V, respectively. An EO measurement system is fabricated. The hybrid films are spin coated on the low reflection mirror and corona poled after aging in order to induce the nonlinear performance. The EO output signals of the two silica films are detected. The experimental results show that the EO output signals change both amplitude and frequency with the input signal. The nonlinearity of the poled DR1/SiO₂ films is relaxed less than 5% after 2000 h at 80°C. The EO coefficient of DR1/TiO₂/SiO₂ films is relaxed less than 5% after 2500 h at 80°C The excellent thermal stability of the hybrid organic/inorganic film has potential applications in the fields of electro-optics and optoelectronics.

White organic light-emitting diodes (OLEDs) were fabricated with red fluorescent dye [7-diethylamino-3-(2- thienyl)chronmen-2-ylidene]-2,2-dicyanoviny-lamine (ACY) by spin coating method, which used a mixture of poly(N-vinylcarbazole) (PVK) and ACY with various weight ratios. The spectra characteristics of different devices were studied and device performance was analyzed. The results demonstrated that optimum device performance could be obtained by choosing a concentration proportion of PVK : ACY at 1000 : 7. In EL spectra of this white OLED (WOLED) at 9 V, the red and green light emission from ACY and Alq3 were all observed. It was found that the ACY is a kind of material of energy transfer. The red fluorescence was emitted from ACY dopant, but energy was transferred from host material PVK. Also, weak concentration quenching was observed in the EL spectra of OLEDs.

The performance of organic light-emitting devices (OLEDs) based on a small molecular fluorene material, 6,6'-(9H-fluoren-9,9-diyl)bis(2,3-bis(9,9-dihexyl-9H-fluoren-2-yl)quinoxaline) (BFLBBFLYQ), was investigated. Double-layer devices with a structure of indium tin oxide (ITO)/BFLBBFLYQ/2,9-dimethyl-4,7-diphenyl-l, 10-phenanthroline (BCP)/Mg:Ag were fabricated. To improve the performance of the OLEDs, N,N'-biphenyl-N,N'-bis-(3-methylphenyl)-1, 1'-biphenyl-4,4'-diamine (TPD) was introduced, and triple-layer OLEDs with a configuration of ITO/TPD/BFLBBFLYQ/BCP/Mg:Ag were fabricated. By analyzing the electric and luminescent properties of the devices with two different structures, it was found that the performance of triple-layer devices was higher than that of double-layer device. The electroluminescent (EL) spectra of the devices were also studied, which showed that the EL spectra red-shifted as the vacuum deposition temperature increased.

We experimentally implement the periodic and quasi-periodic bifurcations routes to chaos based on the semiconductor laser with optical feedback. The effects of the interaction between the relaxation oscillation frequency and external harmonic frequency on the quasi-periodic and period-doubling bifurcations routes to chaos are experimentally analyzed. The results show that the output of the laser evolve into chaos along the period-doubling bifurcations route with the optical feedback strength increasing when the relaxation oscillation frequency is integer multiple of the external harmonic frequency, otherwise, the output of the laser evolve into chaos along the quasi-periodic bifurcations route with the optical feedback strength increasing when the relaxation oscillation frequency is not an exact multiple of the external harmonic frequency. At the same time, the routes of the quasi-periodic and period-doubling bifurcations to chaos are proved theoretically by using the rate equations of the semiconductor laser subject to optical feedback. The results of numerical simulations are consistent very well with our experimental results.

An optical fiber coupler is a very important component in realizing all-fiber communication system. The appearance of dual-core photonic crystal fibers (PCFs) has enabled a new method of designing fiber coupler. Directional coupler based on the dual-core PCFs was investigated and shows intriguing properties, e.g., broadband coupling, the shorter coupling length, and polarized-mode coupling. However, the coupling bandwidth is the one of the most key properties due to the wavelength dependent of coupling efficiency for optical fiber coupler. In order to obtain the wavelength flattened response coupler with insensitive to deformation of air holes, in this paper an asymmetry dual-core PCF coupler with depressed-doped core is proposed and its coupling characteristics are also investigated by full-vector beam propagation method (BPM) in detail. The result of simulation shows that the coupling coefficient of 50%± 0.5% over a wide wavelength from 1.3μm to 1.7μm. Its coupling length is about 394μm, which is much shorter than that of other dual-core PCF couplers reported in literature. The fluctuation of coupling ratio is smaller than 5% with variation of the coupling length of 10%. We also demonstrate it could be more robust caused from the shorter coupling length. Furthermore, the mode field of the coupler is Gaussian-shape which means that additional insertion loss will not be introduced.

The Optical micro-ring Filter is a key component to realize photonic integrated circuits. Various types of micro-ring resonators were proposed and discussed in recent years, and it shows the tremendous potential applications including modulators, filters, sensors, optical delay lines, nonlinear optics and more. The structure parameters of micro-ring resonator were adjusted purposely in order to obtain the desired filtering characteristics. In this paper, a micro-ring resonator based on photonic crystal fiber was proposed and its filtering characteristics were investigated in detail. The influence of structure parameters on filtering wavelength, FWHM and coupling efficiency was presented by using beam propagation method (BPM). The simulation result shows that this PCF filter possess comb-filtering characteristic within the normalized wavelength (λ/Λ) range from 0.21 to 0.947. and shut-down of filtering wavelength could be adjusted by changing the air-hole size. The filtering characteristic is control flexibly because of appearance of photonic crystal fiber, and the fabrication of this kind of PCF filter is easier than that of other kind of filter, e.g., waveguide filter etc. It implies that this kind of PCF filter could be applied potentially in optical fiber communication and sensor system.

Two types of lead-fluoride nano-glassceramics doped with rare-earth ions (Tm, Ho, Pr, Er, Yb) have been developed and synthesized. The size of crystalline phase achieved up to 40 nm. Spectral and luminescence properties of nanoglassceramics have been investigated. It was shown, that emitting probabilities of different transitions changed during thermal treatment. The entry of rare-earth ions in crystalline phase resulted in a broadening of emission spectra. For example, the bandwidth of emission spectrum at 1.55 mkm achieves 70 nm for Er-doped nano-glassceramics. RE-doped nano-glassceramics are promising candidates for different photonics applications, sensors, fiber and waveguide lasers.

In this paper, the theoretical analysis and numerical simulation with regard to the temperature characteristics of LiNbO₃ crystal electro-optic modulator are putted in practice by applying linear electro-optic effect coupling wave theory. The temperature stable conditions of LiNbO₃ crystal electro-optic modulator are theoretically illustrated through optimizing some sensitive factors such as crystal length, lightwave incident direction, and so on. As a result, it can be used as a useful theoretical guidance for the design and practical utilization of LiNbO₃ crystal electro-optic modulator.

A 160Gbit/s optical time-division-multiplexing (OTDM) transmission system with polarization Scrambler is demonstrated experimentally. The Scrambler based on the structure of the all-fiber dynamic polarization controller (PolaRITE II by General Photonics Co.). The polarization controller is controlled accurately the peak scrambling frequencies and the corresponding half-wave voltages by home-made a singlechip circuit. Both theory and experience show that the rate of scrambler is related to the spectrum width, spectral distribution, modulation rate and so on. The rate of Scramble for broadband light would be much slower compare with narrowband light to carrying out depolarization. In the same width of spectrum, light with abundant spectrum would need a slower rate. The relationship between the Rate of Scrambler and the Character of different Lasers will be discussed by using Stokes parameters and Mueller matrix. And the experiments performed to verify the results of theoretical analysis results. The Scrambler can reduce Intersymbol Interference, Polarization Mode Dispersion (PMD) and Polarization Dependent Loss (PDL) that have are validated experimentally. Based on the Scrambler, the 160-Gb/s OTDM transmissions are successfully demonstrated.