Center wavelength shift of vertical cavity surface emitting laser light in arrayed waveguide gratings is verified with mathematical and experimental analysis.It is induced by the linearly increasing trend of optical power of vertical cavity surface emitting laser by bias current increase.It is retrieved effectively to the original center wavelength by simple correction method of compensation.This was done for application of vertical cavity surface emitting laser as a light source in optical line terminal of wavelength division multiplexingpassive optical network.

We are developing an optical layer2 switch network that uses both wavelengthdivision multiplexing and timedivision multiplexing technologies for efficient traffic aggregation in metro networks.For efficient traffic aggregation,path bandwidth control is key because it strongly affects bandwidth efficiency.For this paper,we propose a dynamic timeslot allocation method that uses periodic information of difference values of traffic variation.This method can derive nearoptimal allocation with lower computational cost,which enlarges the maximum available network size compared with conventional timeslot allocation methods.Numerical results show that the proposed method enables dynamic path control in 1Knodescale optical layer2 switch network,which leads to costeffective metro networks.

A novel clock recovery scheme based on inband pilot insertion and extraction was demonstrated for ultrahigh bit rates Optical TimeDivision Multiplexing (OTDM) system. The clock recovery function was realized by inserting and extracting an inband clock pilot located in the data spectrum, which did not need any ultrafast phase comparator or phaselocked loop in the receiver. The scheme allowed fast synchronization, low timing jitter and highly stable recovered clock for OTDM receivers. The clock pilot was constructed with phase modulation and intensity modulation, respectively, which showed errorfree operation of 160to40 Gb/s demultiplexing. The proposed method simplfies clock recovery configuration throught preprocessing of data signal in the optical domain between optical transmitter and receiver, which is compatabile with standard OTDM system after minor modification of optical transmitter and receiver.

Elastic optical networks could increase the sprectrum usage ratio greatly and provide users with flexible bandwidth granularity compared to the traditional wavelength division multiplexing networks. To improve the existing algorithms of routing and spectrum assignment in EONs, An integer linear programming model was set up to formulate the Routing and Spectrum Assignment problem, and two heuristic algorithms were proposed, which combine the traffic grooming with most solts first and longest path first, respectively, thereby increasing the spectrum resource utilization further. The reordering rule and procedure of the proposed algorithms were designed. The expermients under the smallsize network (6node simple network), mediumsize network (14node NSFNET) and largesize network (19node telecommunication backbone network) show that the proposed algorithms could increase the spectrum resource utilization effectively when compared with existing algorithms.

In order to solve the problems of lower nonlinear threshold optical peak power in fiber and more complicated coding algorithm caused by continuous pulse coding technique, a cyclic simplex coding technology and it′s application system in which the coding optical pulses were evenly distributed along the whole fiber were proposed. The comparative experiment adopting 27 km multimode optical fiber between traditional single pulse system and cyclic simplex coding system were made for validating the correctness of theory. The results show that compared to the continuous pulse coding,the cyclic simplex coding not only keeps same signaltonoise improvements to traditional single pulse technique, but also increasese nonlinear threshold optical peak power in fiber,and has more simple coding process in which it just transmits one row codes circularly, so the system can improve signaltonoise ratio and sensing range greatly in the same amount of measurement time. With this coding technology, the system attains ±1.5℃ temperature measuring uncertainty and achieves 3 m spatial resolution on 25 km of multimode optical fiber after 160 000 measurement times.

In order to address the service fairness issue of traffic with different granularities in elastic optical networks, a fairness aware dynamic spectrum allocation scheme was proposed. A novel utility function was introduced to take into consideration the spectrum utilization together with the service unfairness during spectrum allocation process, thus greatly migitating the overall blocking performance deterioration. Simulation results reveal that the proposed scheme migitaes service unfairness problem remarkably without significant blocking performance deterioration.

In order to solve the energy consumption in the data centers with virtualization,the power efficient allocation of Virtual Data Centers was investigated which included three components,namely poweraware embedding algorithm,access policy and defragmentation algorithm.A poweraware embedding algorithm was proposed to allocate resources for Virtual Data Centers in treelike network topologies,and enforce an access policy on the incoming Virtual Data Centers requests to reduce fluctuations in the power expenditure.As requested Virtual Data Centers enter and leave dynamically,there will be resource fragment in the physical network.Therefore,a defragmentation algorithm was devised to migrate virtual machines away from underutilized physical machines.These algorithms were evaluated by simulation and proven effective to smooth and reduce power expenditure over time.

In Orthogonal Frequency Division Multiple Access Passive Optical Network (OFDMAPON) upstream transmission,the Optical Beating Interference (OBI) will be produced if each ONU uses different lasers with the same wavelength.The colorless ONU is hard to achieve with the presence of OBI.The OFDMAPON system structure was studied and the related formulas were derived to analyze the generation and avoidance of OBI.The OBI avoidance scheme that sending optical carrier used in upstream by downstream transmission combined with coherent detection in optical line terminal was simulated.Via simulation,the antidispersion scheme and the effects of dispersion accumulation and the length of training sequence on system performance were studied,and the parameter configuration was optimized to provide a theory reference for practical application.

In order to provide different quantum key service, trusted relay quantum key distribution networks with quantum key pool was studied. Firstly, relationship between packet delay and quantum key pool was analyzed. The formula was given, which showed that the mean packet delay is related to the quantum key generation rate, the initial length of quantum key, the mean length, arrival time and arrival rate of packets. The theory and simulation results verified the accuracy of the delay analysis. Next, the key providing service was classified into three types: guaranteed, prioritized and besteffort key service. Correspondingly, prereserving, hopbyhop jumpingqueue and hopbyhop queuing approaches were presented to realize the above differentialized key services. Finally, simulation results verified the efficiency of the differentialized service providing scheme.

In order to generate a high quality multicarrier, the phenomenon caused by different phase deviation of radio frequency was analysed. In this paper, the theoretical analysis revealed that the quality of multicarrier would deteriorate gradually when the phase deviation decreases from 90° to 0°. But when phase deviation is slightly different from 90°, the quality of multicarrier is good enough for the application of optical communication. In the experiment, the qualities of multicarriers with phase deviation of 90°, 45° and 0° were compared. The best performance is obtained at 90°. Under the 45° phase deviation, fifty carriers can also be otainted, but the quality decreases slightly that is good enough to apply to optical communication. And a multicarrier under 0° phase deviation cannot be obtained.

A novel adaptive chromatic dispersion (CD) compensation method was proposed for digital coherent single carrier systems. Two pulse amplitude modulated pilot tones (PAMPTs) were inserted at both sidebands of the signal in the transmitter. The two line spectra of the PAMPTs can be found by searching the spectrum peaks in the upper and lower sideband. Before CD estimation (CDE), the laser frequency offset (LFO) can be directly estimated from the frequency drift of one of the PAMPTs. Then the signal spectrum was shifted on the reverse of the frequency axis to adjust the received spectrum of OFDE and compensate LFO. After that, the relative time delay between the two line spectra of the PAMPTs was recovered at the receiver and used for CD estimation, while the frequency of the PAMPT recovered was used for spectrum preadjustment of frequency domain CD equalization, Therefor by using this method, the field information of the PAMPTs was fully utilized for accurate CDE and CDC. Numerical simulations show that the CDE error is less than ±65 ps/nm for single time CDE and the averaged error is below ±10 ps/nm for all the distances from 200 to 1 000 km. The method enables much faster and more accurate CD adaptive compensation and reduces computational complexity.

A reflective optical pulse shaping system based on liquid crystal spatial light modulator was built. With changing the modulation voltage loading into the pixel on the liquid crystal spatial light modulator, the system resolution and the relationship between the output including intensity and phase and the modulation voltage were measured. And the modulator′s calibration was discussed. The resules show that the intensity changes with modulation voltage linearly, while the phase is nonlinear. The frequency resolution of pulse shaping system is 10 GHz, corresponding 0.08 nm wavelength resolution, which can realize the modulation of optical signal with frequency interval of 10 GHz. An optical frequency comb with 10 GHz spectral spacing was adoped as the light source. Spectrum shaping was performed and flat spectrum, Gaussian spectrum, triangular spectrum and inverted triangle spectrum were generated experimentally.

The hybrid sleep mode of optical network unit was introduced into ethernet passive optical network for multicast traffic, and the energy saving algorithm for multicast traffic and improved energy saving algorithm for multicast traffic were proposed. The two algorithms sleep the idle components of optical network units and reduce the wakeup times of optical network units by constraints, so that the energy consumption of optical network units can be reduced. Compared with energy saving algorithms for multicast traffic, the improved energy saving algorithms for multicast traffic adds a constraint for optical network units wakeup, so reduces the wakeup times of optical network units further. Simulation results show that, the two proposed algorithms save more energy than the previous algorithm with guaranteed packet delay. Moreover, the improved energy saving algorithms for multicast traffic saves more energy than energy saving algorithms for multicast traffic, which shows that the adding constraint contributes to the reduction of the wakeup times and the energy consumption of optical network units.

A traffic matrix estimation approach for optical transportation networks was proposed.Compressive sensing theory was used to study traffic matrix estimation in optical transportation networks.According to the sparse representation of signals,traffic matrix was processed in the sparse way.Matrix transform theory was exploited to present a new network tomography model for optical transportation networks.This model can overcome the illposed nature of the existing network tomography.Conex optimization was used to attain the estimation equation about traffic matrix.The detailed estimation algorithm is presented.The accurate estimation about traffic matrix for optical transportation networks was obtained.The data from the real network was used to perform the simulation.Simulation results show that the proposed method is effective and feasible.

A 10fold stretchfactor photonic TimeStretch AnalogtoDigital Converter (TSADC) system for a 5 GHz radiofrequency signal is achieved.By adopting the photonic time stretch scheme to compress the bandwidth of RadioFrequency,the effective analog bandwidth and effective sampling rate of the posterior electronic AnalogtoDigital Conversion were improved.The dispersioninduced power penalty of the stretched signal as well as the modulationinduced harmonic distortion were analyzed and simulated.The theoretical analysis and experimental results indicate that the SignaltoNoise And Distortion ratio of the photonic timestretch process is high enough to maintain the high effective number of bit of the posterior electronic AnalogtoDigital Conversers in the bandwidth of 0~5 GHz.In addition,the designed TSADC system can achieve an effective analog bandwidth of 8 GHz and an effective sampling rate of 200 GS/s.

Aiming at some problems of existing optical fiber voltage sensors, such as complex structure, adjustment difficulties, poor temperature stability, optical power loss and voltage introduced inconvenience, a new structure of suspended optical fiber voltage sensor based on all polarization state detection without polarizer and analyzer was proposed. The sensor only contained three main elements that are a selffocusing lens, a Bi4Ge3O12 crystal and a total reflection mirror.For the fewer devices,the structrue is simple and it is easy to align. All polarization state detection system was described. It uses divisionofamplitude method and has fast response and simple algorithm.Formulas about polarization state, electric field and the measured voltage were calculated.Experiment of measuring the high voltage by suspending the sensor was demonstrated. The sensor in the experiment has no electrode and without ground,which eliminates the need for expensive insulators and increases the range of the sensor. The experiment results show that the sensor has a good linearity at room temperature in the range of 0~10 kV AC voltage at powerfrequency,which proves the feasibility of the structure.

In order to reduce the PeaktoAverage Power Ratio (PAPR) of Orthogonal Frequency Division Multiplexing (OFDM), a restorable Clipping scheme is proposed and used in the OFDM and Radio Over Fiber (OFDMROF) system. The algorithm is to set a peak detection threshold on the input signals and the signals can be recorded in an array, at the receiving end, the original siginal can be restored in the array effectively. Simulation results show that the new scheme is not only simple, but also significantly improve the BER and the outofband radiation performance while guaranteeing the PAPR performance of the QAMOFDM system.

A polarization multiplexing scheme for polarization division multiplexing orthogonal frequency division multiple with coherent detectedbased passive optical networks was proposed,in which polarization multiplexing was used at the Optical Network Unit(ONU) for the upstream transmission to increase the transmission data rates and double the spectral efficiency.ONU colorless was realized by optical carrier way.VPI and MATLAB were used for the PMCOOFDMPON simulation platform.The results show that the proposed PMCOOFDMPON architecture is scalable,improves the data rates in the upstream of PMCOOFDMPON,and ONU colorless is realized effectively.Moreover,with coherent detected,the receiver sensitivty is improved.

Prereservation based small buffers is an efficient method for contention resolution in optical burst switching networks. In this paper, the blocking model of prereservation with twoclass state was studied in order to provide differentiated services, and a comprehensive analysis on the blocking performance was exhibited by varying buffer size and traffic ratio. In order to reduce the total loss probability of prereservation with twoclass state, a novel scheme named prereservation based trafficthreshold was proposed by constraining the buffered right of low priority within the specific traffic states. Additionally, through the detailed numercial analysis, the reasonable values of buffer size and trafficthreshold were gained, and the balance of buffer usage between high and low priority was achieved. The simulation results show that comaparing with the conventional prereservation schemes, prereservation based trafficthreshold maintains the total blocking performance in all traffic states and obtains a obvious reduction of burst loss probability in light and moderate traffic states.

A novel design of high birefringent photonic crystal fiber based on schott glass with elliptical air holes in the core and cladding is proposed,and two circular air holes are introduced in the innermost layer of the cladding.Using the finite element method，its birefringence,confinement loss and dispersion characteristics are investigated simultaneously by changing the pitch of air holes and ellipticity of elliptic air holes .Numerical results show that the value of birefringence can be improved by introducing a small elliptical air hole in the core,the birefringence and confinement loss are respectively about 5.22×10-2 and 8.82×10-10 dB/m at 1.55 μm with the cladding air holes pitch size of 1.6 μm and the ellipticity ratio of 0.5.In addition,the fiber keeps normal dispersion in a wavelength range from 1.0 μm to 2.2 μm.In conclusion,this proposed photonic crystal fiber are significant for the further research on the new background material photonic crystal fiber.

A burst loss recovery mechanism based on forward frror correction was proposed to reduce burst loss probability in optical burst switching networks.A new lowdensity paritycheck code was designed to encode and decode bursts online.In the ingress node,encoder generated redundant bursts by encoding information bursts,and in egress node,decoding algorithm was used for recovering lost bursts.For redundant bursts contended with information bursts for wavelength resource and that may result in large information bursts loss,extraoffset time was added for information burst.The performance of different burst loss recovery mechanism was investigated by OPNET simulation software,the results show that the burst loss recovery mechanism can reduce burst loss probability more efficiently compared with pairtycheck codes.Therefore,the mechanism is provided with good capability of burst loss recovery.

In conventional OFDM system,an OFDM symbol will exceeds its guard interval (GI) and seriously interfere with its neighboring symbols when channel characteristic is unsatisfactory.This will cause intersymbol interference (ISI) and intercarrier interference (ICI).In highspeed incoherent optical OFDM communication system,a novel time domain reshuffling method for mitigating ISI and ICI based on DCOOFDM was proposed.This scheme utilized the properties of Fourier Transform.By simple preprocessing subcarrier channels in frequncy domain,sampling sequence of a DCOOFDM symbol in time domain was exchanged interactively.Thus signal energy was centralized in the central part of a symbol.Numerical simulation indicates that ISI and ICI is significantly reduced and system BER performance is improved effectively due to signal surpassing the GI.In optical OFDM systems with insufficient GI for the popurse of higher information transmission efficiency,the reshuffling scheme also has a great value.

Principal component analysis was exploited to extract the principal features of endtoend network traffic and to attain the initial estiamtion results. This results are taken as the prior value of genetic algorithm to overcome its sensitiveness to the prior value. The estiamtion biases of link traffic is regarded as the fitness function of genetic algorithm. The crossover and mutation probability functions are built to control its corossover and mutation processes. The appropriate iterative funtion with contraints is built. The genetic algorithm is used to attain the endtoend traffic estimation results in the iterative way. Simulation results show that the proposed method is feasible.

To improve the reliability of reference map preparation for scene matching, it is necessary to analyze the matching performance of remote sensing image. Remote sensing image matching performance metric was proposed based on independent component analysis. Firstly, texture basis functions are produced based on independent component analysis and a set of probability functions that describe the coefficients distribution corresponding to each of the texture basis functions are calculated to extract matching regions. Secondly, the area ratio index, distribution index and stability index for matching regions are defined. Lastly, remote sensing image matching performance metric is constructed based on the three indexes. The experiment shows that the proposed remote sensing image matching performance metric index is highly correlated to real matching probability. It improves the reliability of reference map preparation and can meet the need of remote sensing images selection for scene matching.

In order to overcome the disadvantage of the background difference method and the frame difference method and improve the accuracy, realtime and detection efficiency for the detection of moving target, a method was presented that combines the continuous frame difference method with the background difference method. The proposed method firstly used continuous frame difference method to obtain continuous difference images. Then a linear adaptive filter or an nonlinear median filter was adopted to obtain the background image and get them subtraction. Finally a threshold segmentation technology was used to enhance the detected moving target. Experiment results demonstrate that the proposed algorithm can effectively avoids the phenomenon of the “missed” and “false alarms”, etc., and the detection efficiency and accuracy are improved greatly.

In order to reduce the Fresnel reflection of optical surface, a method to fabricate bionic antireflective structure was proposed. Originally, silver nanoparticles were deposited on the surface of the rigid substrate based on silver mirror reaction and annealing process, and then following etching process, the motheye nanostructures with antireflective property were formed on the substrate. Optical characteristics of motheye nanostructure for random distribution and period distribution were analyzed theoretically. The results indicate that the random distributed nanostructures have a broad reflective spectrum in the visible region. In experiments, the impacts of annealing parameters and etching parameters on diameter, density and height of nanostructures were analyzed, and antireflective structures were fabricated in silicon and quartz substrate respectively. The results show that less than 4.5% in reflectance is obtained for nanostructures in silicon substrate, and the transmission is enhanced to 98.1% for nanostructures in dualside quartz substrate. In both theory and experiment, it indicates that random distributed bionic motheye structure has a high effect antireflective performance for a broad spectrum and wide angle. The proposed method has advantages of simple, lowlost and largearea fabrication of antireflective structures, and is promising for application on photoelectric device.

Base on the convolution model of material removal and power spectral density function in optical manufacturing, a mathematical model named smoothing spectral function was established. A Zerodur plate mirror with diameter of 620 mm was polished using Rigid Conformal tool. By calculating the smoothing spectral curve, the error restraint ability of polishing process can be expressed as a normalized and nondimensional spectral curve. The calculated result indicates that the error restraint ability of polishing process can be evaluated by the value of smoothing spectral function curve.

A medium infrared optical system was designed for acoustooptic tunable filter spectra camera to obtain the spatial information and spectral information.By introducing a hybrid refractive/diffractive lens,there are six lens in the fore zoom optical system to achieve 12× zoom ratio,which can identify the object 2 000 m far at long focal length.ZEMAX software was used to simulate the diffraction of the crystal,a wedge with 4° is needed to certify that the -1 order diffraction beams exit coaxially.Results show that the maximum modulation transfer function at spatial frequency14 lp/mm of the whole system is 0.7,the diffraction encircled energy was greater than 90%,which satisfy the image quality of the spectrum camera for target identifying and tracking.

Based on photonic crystal oneway waveguide, one threeport system and two kinds of fourport systems were designed. According to coupled mode theory in time, it was confirmed that the channel drop filters on the basis of oneway waveguide have more simple structure than that with only general dielectric photonic crytal waveguides in order to achieve 100% channel drop efficiency, which is benefit to the solution to the fabrication difficulty of the devices. The simulation results calculated by the finite element method shows that the channel drop efficiencies are all over 90%, which does agree well with the theoretical analysis.

In terms of Helmholtz equation and finitedifference timedomain method, a numerical approach for analyzing the directional coupling characteristics based on two SU8 filled slot waveguides was proposed. The mode eigen equation of the coupling slot waveguides was derived and solved, and mode optical field distribution and effective refractive index were achieved. By using the effective refractive indices of the highestorder even symmetric mode and the highestorder odd symmetric modes, the coupling length under TE and TM polarizations was calculated. Numerical simulation results show that when the coupling gap is less than 800 nm, the coupling length is less than 100 μm. The wavelength dispersion characteristics of the used materials were measured with an ellipsoidmeter, and then the wavelength dispersion of coupling length and mode loss of the coupling slot waveguides were investigated. The analytical results reveal that the coupling length decreases as the wavelength increases under both polarizations, and under the same coupling gap, the coupling length under TM polarization is larger than that under TE polarization. The coupling lengths under TM and TE polarizations are 28.2 and 26.2 μm, respectively, when wavelength is 1 550 nm and coupling gap is 0.5 μm. In addition, the mode loss also decreases as wavelength increases, and the mode loss under TE polarization is larger than that under TM polarization. The loss coefficients under TE and TM polarizations are 5.65 and 3.16 dB/cm, respectively, when the wavelength is 1 550 nm.

For thermal problem existed in high power LED, a new heat exchanger based on double inlets and double outlets water jet was proposed. The different cooling effects between the radiator proposed and the current jet cooling radiator were discussed, an experimental platform of high power LED cooling system base on water jet was designed. Under the condition of full power output of the cooling system, the LED substrate′s temperature is distributed and remained at 32℃ in experiment, which shows that the cooling system has excellent abilities in uniforming temperature and distributing heat which the LED produced. And the experiment proves that the system meets the thermal requirements of the high power LED. The effect weights of the pump and the fan were obtained and the consumption power of the cooling system was optimized by using extremum difference analysis. Besides, a set of optimum pulse width modulation signals controlling pumps and fans were obtained through the experiments and analysis. The power consumption of the cooling system was reduced and the energy was saved with these signals.

Wavelength conversion using electroabsorption modulator was analyzed for two operating conditions:without delayed interferometer structure and with delayed interferometer structure.It′s proved by 10Gb/s returntozero signal wavelength conversion experiment that long pulse trailing edge of the converted signal can be mitigated obvisouly and the exticion ratio of the coverted signal can be improved sigificantly.Meanwhile,the influencen of operating parameters including bias voltage,data signal power,and wavelength on conversion performance were studied in detail.It′s found that the proper setting bias voltage can optimize receiver sensitivity of the converted signal for two operating conditions and delayed interferometer can introduce nearly 2.0 dB sensitivity gain under -3.0 V bias voltage.

Based on symmetrical metalcladding waveguide, the effect of temperature on permittivity of metal layer and refractive index of waveguide layer was studied. By changing the metal permittivity and refractive index of waveguide layer, resonance angle and attenuated total reflection absorption peak were affected. Theory and simulations show that as the temperature rises from 10℃ to 70℃, attenuated total reflection absorption peak decreases and absorption rate improves with increased temperature; resonance angle increases and then decreases with increased temperature on the condition that the wavelength of incident light is 760 nm, the thickness of silver film coverage and silver film substrate is 35 nm and 300 nm, the guiding layer is pure water. When the effect of metal permittivity on the overall is greater than pure water, the resonance angle increases. On the contrary, the resonance angle decreases. Therefore, the temperature effect on the symmetrical metalcladding waveguide can not be ignored.

Considering the radial component and azimuthal component of the vortex beam in focusing contribution, the tightly focusing formula of Cylindrical Vortex Beams(CVB) was amended. The CVB focusing intensity distribution was afresh investigated in the focal region by using amendatory tightly focusing formula. The results show that the flattopped focus and the focal hole are proposed by adjusting the Polarization Rotation(PR) angle, NumericalAperture(NA) and the Aperture Blocking(AB). The adjustably confined flattopped focus can be generated by adjusting PR angle. And the flattopped focus can be obtained for the relative small NA with the increasing of AB. The narrower focal hole can be obtained in the higher NA when AB is larger.

Based on the methods of vector angular spectrum and stationary phase, the analytical expressions of the TE and TM terms and the energy flux distributions of sinGaussian vortex beams in the far field were derived and used to analyze the phase singularities and energy flux distributions. It is shown that the farfield properties of sinGaussian vortex beams are dependent on the waist width of Gaussian beam, offaxis distance, position of coordinate and parameter related to the sine functions. Under certain conditions phase singularities and black nuclei of the energy flux distributions will appear in the far field. By changing the controlling parameters of the beams, phase singularities and black nuclei excluding those at the origin will vary. The symmetry of the phase singularities and the energy flux distributions is dependent on the vortex offaxis distance. The distributions of phase singularities and energy flux are symmetrical about the origin in case the offaxis distance is zero. With varying the offaxis distance the asymmetry may take place and the results were analyzed.

A spectrum testing scheme of optical passive device based on LabVIEW was proposed. Relying on LabVIEW programming control over tunable laser, programmable optical filter, optical power meter and data acquisition (DAQ) platform, spectrum characteristics of various transfer functions could be obtained. When laser sweeping speed was 10 nm/s, sweeping range was 10 nm, and DAQ sampling rate was 1 MS/s, spectrum measurement for one device could be finished in 1 s, with spectrum resolution of 1 pm. Compared with conventional spectrum testing method utilizing broadband light source and Optical Spectrum Analyzer (OSA), the performance test scheme could achieve the traditional scheme level, and got more delicate spectrum details. The experimental results show that the proposed scheme can be applied for spectrum measurement with the demand of high resolution, fast speed and high efficiency.

Chalcohalide glass based on the composition of GeGaSCsI (GGSI) doped with Nd3+ (0.5 wt.%) was synthesized with the traditional meltquenching technique.The synthesized glass material was used to fabricate large refractive index (n≈2.1) microspheres using an improved flowing powders method.The fabricated spheres have diameters ranging from 50 to 300 μm.Microspheres with good surface quality were selected for the following coupling experiment.Biconical tapered fibers with waist diameters of 1~2 μm were fabricated with a flameheating process.They were then coupled with the selected GGSI glass microsphere via phasematched evanescent waves.The phasematching condition between the sphere and the fiber predicted high order radial modes in microsphere would be excited by the evanescent field of the fiber taper.In experiment,an 808 nm Laser Diode (LD) was used as the excitation source and fluorescence emission spectra of the selected microsphere were measured.Periodically spaced intensity peaks around 1 075 nm,which indicated Whispering Gallery Mode (WGM) optical resonances occurred in the Nd3+ doped GGSI glass microsphere,were clearly observed in experimental results.The typical spacing between two resonance peaks is 1.80 nm,which is in good accordance with the theoretical prediction.

To realize the target spectrum matching of CIED65 standard illuminant and AM1.5 standard solar spectrum by employing monochromatic LED, a simple genetic algorithm as the spectral matching algorithm was proposed, by solving nonnegative least square solution of overdetermined equations, the combination of monochromatic LED light source with different peak wavelength, peak wavelength interval and full width at half maximum was optimized, and the light source spectral matching was achieved. Simulation results show that the fitting correlation index is above 0.99, the fitting spectrum is consistent basically with the target spectrum. The smaller the interval of spectral matching peak wavelength is, the better the spectral fitting effect is, to meet the needs of engineering application, the peak wavelength needs to be selected moderately. The proposed algorithm runs fast, has high efficiency and small fitting error, and it can be widely used in the spectral matching simulation test and engineering practice for special lighting fields such as plants lighting, medical lighting and so on.

The parameters and property of Offner imaging spectrometer were studied according to eliminating aberration structure. The calculating equations of measurable range of wavelength, linear dispersion and spectral resolution were deduced by geometry method based on eliminating aberration structure of Offner imaging spectrometer; the relationship of resolution and each factor were analyzed, these factors including width of entrance slit, convex grating resolution and pixel size of detector. When the system aberration was to be ignored, the spectral resolution could be enhanced by decreasing width of entrance slit , this conclusion was verified by imaging experiment. The techniques and methods of improving spectral resolution were summarized, the tradeoff balance between each parameter and spectral resolution were considered. The final conclusion was as follow: the resolution of Offner imaging spectrometer was determined by the lowest resolution of the entrance slit, convex grating and pixel size of CCD.