In order to reduce the center offset error in aspheric surface testing by annular subaperture stitching interferometry, the mechanism of action of center deviation error in the surface shape measurement was analyzed, and the error model based on the testing principle and geometrical relationship was established. A compensation method for the center offset error based on two-dimensional matrices of pixel was proposed. The method is effective for searching the center offset of the initial surface shape measurement data and reducing the eliminate error of the wavefront error caused by the center offset error, and the error among the centers of annular subapertures can also be decreased. The error compensation experiment for the annular subaperture stitching interferometry was carried out with Zygo interferometer. The errors of peak to valley value and root mean square are －0.015λ and 0.003λ respectively compared with the null aspheric surface testing result. The experiment results show that the proposed method greatly reduces the surface measurement errors and improves the measurement precision of annular subaperture stitching interferometry.

An experimental facility designed for the calibration of silicon trap detectors against a laser-based cryogenic radiometer at three laser wavelengths in the Ultraviolet (UV) region was described. The experimental results for the spatial nonuniformity and nonlinearity of the silicon trap detector were shown and discussed. The component uncertainties associated with the measurement of radiation power and spectral responsivity of silicon trap detectors were analyzed. As the secondary detector standards, the expanded uncertainty of the spectral responsivity at three UV laser lines 266, 325, 379 nm is 0.19%, 0.14%, 0.11%, respectivily. This can improve the calibration capability of UV band spectral radiance.

According to the needs of full range and high precision measurements of methane concentration in coal mine safety production monitoring system, a full-scale integrated laser methane sensor was designed based on a Tunable Diode Laser Absorption Spectroscopy (TDLAS). A 1 653.72 nm Distributed Feedback Laser(DFB) semiconductor laser was employed as the system light source. Laser driving, temperature controlling, signal modulation and demodulation, and concentration calculation were realized by a single board circuit. To meet a high measurement precision and a large dynamic measurement range simultaneously, the wavelength modulation technique was used to detect the methane at a low concentration. When the gas concentration is higher than the threshold set in the system, the direct absorption detection technique was switched to automatically. Experimental results show that, the measurement error is less than ±0.06% in the range of 0～5% and less than ±6% of the actual value in the range of 5～100%, and the response time is less than 15 s, which meets the requirements of the mine measurement in practice.

In order to investigate the output variation of the silicon solar cell under the solar simulator and its internal carrier transport properties, light soaking in situ of crystalline silicon solar cell technology was conducted before the standard test which measures the cell's current-voltage characteristics, spectral response and other parameters. The results show that the attenuation of current-voltage characteristics results in reduced efficiency. The short wavelength spectral response of solar cell is decreased slightly after light soaking in situ. The reason is that the surface of the cell generates a very small amount of defect during the light soaking process whichleads to slight decrease of the carrier recombination. The significant decrease of the spectral response during the long wavelength is due to a large number of the bulk defects being activated, which results in the long-wave carrier recombination when it passes through the silicon.The solar cell was then annealed and tested after light soaking. The results show that annealing has a good effect on the recovery of bulk defect deep inside the cell. There is a partial recovery of bulk defects after annealing while the surface defects are not recovered, which leads to the incomplete recovery of current-voltage characteristics and spectral response.

A fringe position measurement method is proposed based on the spatial optical path difference modulation, which is applicable to fringe searching and fringe tracking. When combining the two beams from the two ends of a baseline, a static optical path difference modulation is brought in by a beam combiner introducing tilt angle. An imaging lens is used to image the interferogram onto a CCD detector. The translation of the white-light fringe packet is related to the optical path difference between the two combined beams. The position of interference fringe can be computed with the acquired fringe and used to calculate the path difference. The evaluated optical path difference value is further used to cancel the path difference error by the delay line and to stabilize the fringe. The numerical simulation and experimental results indicate that the maximum experimental measurement error is 0.159 μm, which is smaller than the average wavelength 0.555 μm of the broadband light used in the research, the proposed method can achieve the accuracy that meets the requirement of fringe coherencing . Compared with the previous temporal optical path difference modulation method, the proposed method is simple in principle and algorithm implementation, moreover insensitive to atmospheric turbulence.

The optical transfer function of 30m telescope tertiary mirror under arbitrary forms of vibration was obtained by numerical method, and the accuracy was analyzed. The normalized point source sensitivity was introduced to present the influence of internal vibration on the light beam transmit function. To verify the theoretical analysis, a larger aperture telescope was experimented. In the experiment, a multi-accelerometer method was used, the decoupling of the mirror rigid body motion and the constrain of the testing error were realized by data collected by the residual accelerometers. The results demonstrate that, under the influence of the internal vibration source, the normalized point source sensitivity degrades from 0.99996 to 0.99992. After passing the filter the output force is 0.075N.

A circular primary mirror of an off-axis three mirror anastigmat space camera with an aperture of 610 mm was ultra–lightweight designed to meet the requirement of designing lighter and better satellite cameras. By choosing the back-centre-single point supporting way, using the variable rib thickness and the variable rib height sturctural style and combining with the integrated optimization design method, the mirror was designed with a weight of only 6.23 kg and the surface density about 21.3 kg/m2. The support structure for the mirror was designed and the static and dynamic performances of the mirror subassembly were simulated. The simulation results show that the surface figure error (RMS value) is less than 6nm when the mirror subassembly is under the load condition of gravity in three different directions and is less than 1nm when the temperature variation is within ±4℃. The first-order natural frequency of the mirror subassembly is 112 Hz. The results of frequency response analysis present that the maximum stress in the screw hole of the flexible structure is below the yield strength of its material. All performance indexes of the ultra-lightweight mirror designed in this paper meet the requirements of design and the maximum aperture of the mirror which can be supported by single point in centre is 610 mm. The design proposes a method and reference to ultra-lightweight design of same type mirrors.

The lower waveguide of 2 μm InGaAsSb/AlGaAsSb laser diode is optimized based on the research of the asymmetric waveguide. With the introduction of dual waveguide, the 2 μm InGaAsSb/AlGaAsSb laser diode has a high output power, a small far field divergence and good single-mode characteristics. The SimLastip simulation of the 2 μm InGaAsSb/AlGaAsSb laser diode with different waveguide structures were established using the related physical model and software design language. And the results indicate that the dual waveguide can almost double the laser power by decreasing the confinement factors of active region from 0.019 2 to 0.011 3 and obtain the good beam quality with small far field vertical divergence angle of 48°. The dual waveguide can favorably improve the performance of 2 μm InGaAsSb/AlGaAsSb laser diode.

To obtain the high power dual-frequency laser source for lidar-radar system, a narrow-linewidth Nd∶YAG monolithic nonplanar ring-oscillator laser with central wavelength of 1 064 nm was uesd as a single-frequency seed laser. The output was split into two parts, one was transmitted in optical fiber and the other was frequency shifted by an acoustooptic modulator. The combined beam had power of 20mW and contained two frequency components with frequency separation of 150 MHz. A three-stage master oscillator power amplifier using diode laser pumped and Yb3+-doped quartz fiber as gain medium was proposed to boom the output power of dual-frequency laser. The maximum amplified power was 50.3 W, beam quality factor was 1.30 and the slope efficiency of the third-stage main amplifier was 74%. The amplitude ratio and frequency separation of the dual-frequency components were maintained in the amplification process. The modulation depth and signal-noise ratio of the beat signal had not deteriorated. Dual-frequency laser fiber power amplifier provides robust performance of both the stable beat frequency and the relative high output power.

The continuous-wave Mid-Infrared Radiation(Mid-IR) was experimentally obtained by difference frequency quasi-phase-matching in a MgO-doped periodically poled LiNbO3 crystal (MgO∶PPLN), which the narrow linewidth light sources with 1 083 nm and 1 550 nm were used as pump light and signal light,respectively. Moreover, the multiple mid-IR wavelengths were realized by adjusting the signal wavelength and using the temperature controlling on a MgO∶PPLN. The wavelength tuning region is around 3 547.6 nm to 3 629.1 nm. A maximum mid-infrared radiation power of 3.2 mW at 3 597.0 nm is generated when the optical power of signal and pump lights are amplified to 3.5 W and 2.8 W respectively. The power jitter of mid-infrared output is less than ±1.6% after along time test recording. This study can be used as a reference for the design and development of narrow line width multi-wavelength continuous-wave infrared light source.

Under the condition that the local-field effects in photonic crystals have been considered, a field average method based on the effective medium theory was used to calculate the effective linear refractive index of a two-dimensional triangle-lattice photonic crystal in the first band. The calculated refractive index agrees well with that obtained directly by using the plane-wave expansion method. Furthermore, a slow-light enhancement factor was introduced to calculate the effective nonlinear refractive index coefficients. The calculated nonlinear coefficients of the photonic crystal is strongly dispersive: the nonlinear coefficient decreases slowly to the minimum and then goes up quickly. The frequency-dependent nonlinear coefficients directly demonstrate that the local-field effect and slow light effect influence the nonlinear effects in the photonic crystals simultaneously. The results may be helpful for tuning the nonlinear effects by using man-made microstructures.

A photonic crystal fiber with As2S3 glass core and tellurite glass micro-cladding was designed. This design is a perfect conbination of both traditional step index fiber and photonic crystal fiber and own the characteristics of high dispersion adjustment flexibility and low confinement lose. Simulation results show that, by carefully optimizing the characteristic structure parameters such as the fiber cladding air holes diameter , air hole pitches and fiber core diameter of this fiber, and while letting the parameters above meet linear relationship with fiber length, the dispersion profile of this fiber will be flattened and decreasing with fiber length in mid-infrared region of 2～4.5 μm. In addition, we optimized the dispersion of this fiber by filling the air holes of micro-cladding with oil which linear index is around 1.6. Fiber with such novel dispersion property is rare and will be of great importance in applications of laser pulse compression and stretching, dispersive wave generation, soliton and mid-infrared super-continuum generation.

The Ultraviolet (UV) communication network which is based on the space division multiplexing technique will be faced with the problem of inter-link multi-user interference. For a set of typical communication link models, based on the theory of multiple-scattering, and Monte Carlo method was used to analyze the relationships between the probability of error and the distance from transmitter to receiver, the angle between two links, transmitters′ elevation angle and receivers′ elevation angle, respectively. The results show that, the probability of error increases with the increase of the distance from transmitter to receiver, the communication distance should be less than 120 meters when emission power is 100 mW; with the increase of the inter-link angle, the probability of error decreases first, then remains the same gradually, and then increases, the inter-link angle should be within 60°~120°; the influence of the elevation angle of transmitter and receiver on the probability of error is almost the same, that is the probability of error decreases first and then increases rapidly with the increase of the elevation angle, the minimum probability of error at 15°.

Frequency division multiplexing based on long-period fiber grating Mach-Zehnder Interferometer(MZI) is an important way to implement fiber multiparameter sensing. The Fourier method for the composite fringes in freqency division multiplexing was investigated, with emphasis on the relationship between the value of different frequency and sum frequency in the Fourier frequency spectra and the structral parameters of the single grating in fiber MZI and then, an effect method for depressing the different and sum frequencies was proposed. The results show that the singal to noice ratio can be effectively improved by properly selecting the grating structual parameters to reduce the fringe contrast at central wavelength to a certain extend, which improves the effectiveness of filtering in freqency domain.After adjustment and optimization, the singal noice ratio of the frequency spectrum is doubled comparing to the original value. A comparison between the cosine curves of recovered phases and the orignal fringes confirms that the tuned frequency spectra remain sufficient phase information that characterize the original fringes. The spectrum optimization method developed in this paper can provide theoretical and technical guidance for multiparameter sensing based on fiber grating MZI and freqency division multiplexing.

A swept source endoscopic optical coherence tomography system was designed with the grin-lens, single mode fiber and fiber optic rotary joint for endoscopic imaging. The effects of the pitch of the grin lens and the distance between the single mode fiber and the grin-lens on system performance were then analyzed with Zemax. The object distance of 0.7 mm was chosen according to the diameter of esophagus and the Pitch of 0.24P was chosen according to the cost and the effects analyzed above. The measurement results shown that the axial resolution of the system is ~9 μm and the lateral resolution is ~19.5 μm with the imaging depth of 6 mm in air. The working distance of the probe is about 7 mm. The initial cross-sectional images of the intestinal tract of pig were presented to demonstrate the capability of the system for endoscopic applications. And all these results demonstrated that the probe designed is suitable for endoscopic imaging of esophagus.

In order to improve imaging quality of the single compressive sensing ghost imaging and reduce the internal and external interference, the intensity spread function analysis of single compressive sensing ghost imaging was proposed. The imaging process was analyzed based on the principle of single compressive sensing ghost imaging. It is found that Fresnel diffraction and atmospheric turbulence are main causes which result in poor imaging quality. Aiming at these two factors, the formulas of intensity spread function were derived, and the influence of focal length to aperture lens ratio and source wavelength on ghost imaging were studied. Simulation results of single compressive sensing ghost imaging indicate that the effects of diffraction can be restrained by using the projection lens with the ratio of focal length and aperture in the range of 2~5. Besides, the short wavelength is suitable for imaging under the weak atmospheric turbulence. By contrast, the long wavelength is a better choice for imaging under strong atmospheric turbulence. The experiment verifies the conclusions of simulation. Therefore, the proposed method is effective to improve imaging quality and optimize the imaging system.

In order to study the photoluminescence properties of freestanding porous silicon filled with CdS nanopaticles, a freestanding porous silicon was prepared by using a p-type silicon wafer with a resistivity of 0.01~0.02Ω·cm by two step anodic oxidation method as the first step, and then CdS nanoparticles were filled into the freestanding porous silicon by the electrophoresis method. The morphology, phase structure, composition and luminescence properties of the prepared samples were characterized by scanning electron microscopy, X-ray energy spectrum analysis, X-ray diffraction analysis and photoluminescence analysis. The results show that, the CdS nanoparticles are successfully filled into the freestanding porous silicon, and CdS nanoparticles present (210) diffraction peaks. The luminescence peak of CdS nanoparticles filled freestanding porous silicon is find red-shifted from 570 nm to 740 nm. The electrophoresis time directly affects the filling amount of CdS nanoparticles, resulting in the changes of the peak intensity and the peak position.

Ho3+/Yb3+ doped germanate glasses adapting for K+-Na+ ion-exchanged waveguide were fabricated. Upconversion fluorescence has been measured by absolute spectral measurement system under 975 nm diode laser excitation. Net absorption and emission photon distributions and quantum yields were derived from absolute spectral power distributions. Experimental and calculation results revealed that the effective diffusion coefficient of K+-Na+ thermal ion-exchange is 0.068 μm2/min, when Ho3+/Yb3+ doped germanate glasses are immersed in KNO3 molten salt at 370℃ for 4 hours. Ho3+ in germanate glasses emits 548 nm green and 660 nm red fluorescence, and the red one plays dominant role. The absolute spectral powers and the net emission photon numbers of the red upconversion emission are 28.03 μW and 9.26×1013 cps, when pump power density is adjusted to 1 227 W/cm2. The fluorescence quantum yields of 548 nm green and 660 nm red emissions are 0.17×10－5 and 2.41×10－5, respectively, and the total quantum yield in the visible region can reach to be 2.61×10－5 simultaneously. The slope of logarithmic curve of net emission photon number versus excitation power density indicate that the red and green upconversion emissions in Ho3+/Yb3+ doped germanate glasses are both due to two-photon excitation processes. Absolute characterization for the upconversion fluorescence from Ho3+ in waveguide-typed germanate glasses have been achieved, which provides reliable reference in developing rare earth optoelectronic functional materials.

An optical sensing structure was designed to detect the single Nanoparticle. The structure consists of a dual-ring, a nanopore in the coupling area and a straight waveguide, and the Fano effect is introduced. The proposed structure could further amplify the change of coupling effect due to the presence of nanoparticle. Nanoparticles flowing through a nanopore between microrings could change both the coupling coefficient and the optical intensity at the output. An ultrahigh precision method for coupling coefficient sensing was proposed based on a dual-microring resonator structure. The counting and sizing of nanoparticle could be achieved by detecting the change of optical intensity and coupling coefficient. The theoretical results show that the sensitivity of the dual-ring design is calculated to be around two orders of magnitude greater than a single-ring design under 1dB/cm loss condition. The propose structure can improve the sensitivity effectively with reducing the waveguide loss.

A type of fluorine doped dual core photonic crystal fiber polarization light splitter was designed by introducing fluorine in photonic crystal fiber silica materials and seven elliptical air holes and triangle and rectangular periodic air hole in this fiber. The structural parameters were optimized through the study of some parameters in the split structure and the performance of the split two orthogonal polarized light was analyzed.The results show that : in the optimized structure size, when the length of optical fiber is taken as the length of ultrashort 102.717 μm,it has a super separate ability which the two beams of orthogonal polarized light at the wavelength of 1.55 μm, the extinction ratio can reach 126.442 dB. Also, with 60 nm effective bandwidth.Therefore,this polarized optical splitter has an important application value in large capacity optical communication system.

Phase compensator is a key element in the polarized interferometer, whose stability has a directive influence on the reliability of the polarized interference spectroscopy. The specification of the phase compensator such as the relative sensitivity of optical path difference, the tilted error tolerance of optical wedge, the oblique incidence angle error tolerance and the temperature adaptability were studied, and the corresponding calculated formulas were derived. The anti-interference ability of the moving optical wedge is 2/Δnsinθ times stronger than the classical Michelson interferometer. The ability of the moving wedge to resist the inclination is 1.75/Δn times higher than classic Michelson interferometer. After light′s incidence with small angle, there are no additional optical path. The greatest optical path distance error of the phase compensator is 1.8 μm when the temperature changes from ―20℃ to 85℃,which has a good thermal stability. The angle of the wedge is also an important parameter to affect the phase compensator. If setting the angle of the wedge as 30°, a good balance between performance, size and cost may be achieved. The birefringence difference of crystal material is smaller than one, so the stability advantages of the polarized interferometer are very obvious which build up a good basis for its field application with complicated surroundings.

A reliability evaluation method was proposed for Light Emitting Diodes (LED) which the optical performance is declining nonmonotonicly. The accelerated degradation test was conducted in order to obtain luminous flux degradation data. A bi-exponential degradation model was used to fit the lumen maintenance degradation data. Comparing the model with exponential model in fitting effect, indicates that the bi-exponential model provides a good fit to the date. The pseudo failure lifetime was tested and analyzed by MATLAB program. The distribution type of pseudo failure life was determined by using Kolmogorov-Smirnov (K-S) test. The results showed that, the pseudo failure lifetime distribution of samples from two companys obeys Lognormal distribution and Weibull distribution, respectively. And the reliability evaluation of LED is made by the corresponding distribution parameters. It was obtained that the pseudo failure lifetime of samples from two companies is 5 328.37 h and 4 758.35 h, respectively. This method shows a certain reference value to reliability evaluation on nonmonotonic degradation law of LED.

The existence of Majorana fermions in hybrid semiconductor/superconductor heterostructures was studied, and an all-optical method to probe the Majorana fermions by using coherent optical spectra was presented. A strong pump laser and a weak probe laser were acted on semiconductor quantum dot, and the coherent optical spectra were derived by the Hamiltonian of system. The numerical results indicate that the coherent optical spectra present a distinct signature of the coupling between the semiconductor quantum dot and the Majorana fermions in the optical detection method. The characteristic of non-contact between the semiconductor quantum dot and the Majorana fermions can make the detection process avoid introducing noises. The coupling strength between the semiconductor quantum dot and the Majorana fermions is proportional to the distance of two the peaks in the probe absorption spectrum, so that the coupling strength can be obtained by measuring the distance of two the peaks, which presents a straight forward means to determine the coupling strength.MOURIK V, ZUO K, FROLOV S M, et al. Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices［J］. Science, 2012, 336(6084): 1003-1007.

By employing the Master Equation theory, the lasing properties of the quantum dot-microcavity coupling system were studied. For different types of coupling systems, i.e., “good system” and “more realistic system”, their lasing phenomenon under external pump field were investigated individually. Moreover, the influence of the detuning and the pure dephasing on internal characteristics of the coupling system, such as its second-order correlation function at zero time delay or the number of photons in cavities was analyzed. The numerical simulations show that, for a “good system”, when the detuning between a quantum dot and a cavity is not very large, the certain pure dephasing can improve the lasing properties of the coupled system; for a “more realistic system”, due to the difficulty of photon gathering in a cavity under off-resonant conditions, it is very hard to observe the lasing phenomenon. However, the pure dephasing will still play an important role on modulating the light field and the photon numbers in the cavity. These results may play positive effects on some research either on lasing with the single quantum dot, or modulating the interaction between light and matter etc.

The linear entropy and atomic inversion and entropy squeezing in a system of double two-level atoms interacting with a single mode light field at Pólya state under intensity dependent coupling condition were studied by means of full quantum theory. The influences of the initial state of atoms and different parameters of the light field and parameters of Lamb-Dicke on the linear entropy, atomic inversion and entropy squeezing were discussed. The results show that, when the atom in different initial states, the quantum properties of the system are completely different. The period of oscillation increases with the light field parameter of p. Increasing the value of the light field parameter r, which causes the amplitude change and the collapse-recovery phenomenon and the entropy squeezing are destroyed.

According to the spectral distribution function and the extinction factor of the ice crystal and the water droplet in the ice-water mixed clouds, the attenuation relationships between the ratio of ice and water and the channel of the quantum satellite communication were attained. For the bit flipping channels and the depolarizing channels, the equations between the ratio of ice and water and the channel capacity, and the channel average fidelity were established respectively. The effect of the ratio of ice and water in the ice-water mixed clouds on the quantum channel establishing rate was analyzed. The simulation results show that, when the ratio of ice and water in the ice-water mixed clouds is 1∶2 and 1∶9, for the bit flipping channel, the channel capacity is 0.65 and 0.92, and for the depolarizing channel that is 0.59 and 0.95 respectively. When the probability of the source character is 0.9, for the bit flipping channel, the channel average fidelity is 0.60 and 0.83, and for the depolarizing channel that is 0.89 and 0.95 respectively. When the transmission distance is 2 km, the fidelity of the entangled particle pair is 0.8, the quantum channel establishing rate is 7.40Hz and 15.57Hz respectively. Therefore, when the quantum satellite signs are appearing a greater attenuation, in order to improve the reliability of the quantum satellite communication, the parameters should be adjusted adaptively in light of the ratio of ice and water in the ice-water mixed clouds.