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CaF₂:Yb³⁺,Er³⁺ upconversion nanoparticles (UCNPs) were synthesized by hydrothermal method. The green and red light from ²H_11/2/⁴S_3/2→⁴I_15/2 and ⁴F_9/2→⁴I_15/2 of Er³⁺ were investigated in detail by using the power depended luminescence intensity under 980 nm excitation. Afterwards, the as-obtained sample was proved that it had good temperature sensing property in the range of 293-573 K based on thermal coupled levels (TCLs) of Er³⁺(²H_11/2/⁴S_3/2), simultaneously the maximum sensitivity of sample was obtained at 483 K (0.002 85 K^-1) by utilizing fluorescence intensity ratio (FIR) technique. All the experiment data indicate that the sample has great luminescence property and excellent potential in temperature sensing.

Y₂O₃ doped with Eu³⁺ nanosphere phosphors with different sizes were synthesized via urea homogeneous precipitation method. By changing the molar ratio of rare earth to urea precipitant, the uniform spherical Y₂O₃:Eu³⁺ nanoparticles with the sizes of 80, 55 and 40 nm were obtained. The phase, morphology and luminescence property of as-prepared samples were characterized by means of X-ray diffraction (XRD), filed emission scanning electron microscopy (FE-SEM) and photoluminescence spectra, respectively. The growth process of Y₂O₃:Eu³⁺ nanoparticles was studied. The refractive index of Y₂O₃ was deduced to be about 1.80. Meanwhile, the radiative transition rates, fluorescence branching ratios and J-O parameters were calculated by using the emission spectra and fluorescence decay. Finally, the temperature dependence of ⁵D₀ fluorescence emissions was analyzed. The thermal quenching behavior of ⁵D₀ fluorescence followed well the Crossover model. The activation energy of Y₂O₃:Eu³⁺ nanosphere phosphors with different sizes was obtained from the nonlinear fitting on the temperature quenching of luminescence intensity. The activation energy of Y₂O₃:Eu³⁺ nanosphere phosphors with the size of 80, 55, 40 nm are 0.201, 0.193, 0.200 eV, respectively.

Ba_1-xCa_xMoO₄ polycrystalline solid solution films were prepared in the alkaline solution containing Ca and Ba ions via galvanic cell method at room temperature. The as-prepared films were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectronic spectroscopy (XPS) and fluorescence analysis (FA), respectively. The influences of Ba mole fraction on the crystal structure, morphology and luminescence property were investigated. The experiment results show that the prepared Ba_1-xCa_xMoO₄ films are uniform, dense and well-crystallized, having a tetragonal structure. The surface morphology of the obtained Ba_1-xCa_xMoO₄ solid solution films gradually transform from that of CaMoO₄ to that of BaMoO₄ with the increase of Ba content in the initial solution. Excited by 290 nm ultraviolet ray at room temperature, all the as-prepared Ba_1-xCa_xMoO₄ films show two broad emission bands centered at 350 nm and 495 nm, respectively, and the emission intensity of the band located 495 nm is obvious greater than that of the band located at 350 nm. The molar ratio of Ba/Ca has little influence on the shape and wavelength for the emission bands of the obtained Ba_1-xCa_xMoO₄ films, whereas it has markedly influence on their emission intensity.

O-carboxymethyl chitosan was prepared by the carboxymethyl chitosan, and the folic acid-O-carboxymethyl chitosan compounds were prepared by ion crosslinking method. The samples were characterized by means of infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The influences of the mass ratio of folic acid and carboxymethyl chitosan on the composite microstructure and properties were discussed. The coagulant and hemostatic properties of the folic acid-O-carboxymethyl chitosan compounds were explored by tail blood method. The results show that the blood coagulation and hemostatic effects of the folic acid-O-carboxymethyl chitosan compounds are remarkable. When the mass ratio of folic acid and carboxymethyl chitosan is 2:5, the interaction force between folic acid and carboxymethyl chitosan is the strongest, the complex structure is the most stable, and the blood coagulation and hemostatic effect is the best.

The current step accelerated stress tests were carried out at 10, 12, 14 A for 975 nm high power semiconductor laser which is packaged with the way of COS. The test results were analyzed by using the inverse power law model and the exponential distribution theory. The average life of the device is 28 999 h under the current of 8 A. The high power semiconductor laser's failure and the change of temperature rise and the degree of polarization before and after aging were also studied. The results show that the main failure is internal degradation, deterioration of the cavity surface, and welding related degradation. The junction temperature of device after aging is higher, and the degree of polarization decreases about 10%.

In order to study the output far field characteristics of optical fiber coupled laser diodes, several kinds of fiber coupling structures based on single emitting diode laser chip were simulated by ZEMAX optical design software, the analysis on the far field characteristics were conducted. The simulation results show that the far-field output distribution of a single emitter coupling structure is usually a circular spot with a brighter center and a weak light zone outside. When the size of the collimation beam in the fast axis and slow axis is approximately the same, the far field output uniformity improves greatly. When the angular error of optical fiber along the central axis is large(more than 1°), the uniformity of the output far field spot reduces significantly. For multi-chip fiber coupling, if the step height between single emitters is greater than the size of the collimated beam in the fast axis, the output far field distribution is ring-like with dark zone, and the number of the emitters is corresponding to the number of rings. In order to improve the uniformity of the output far field distribution, the step height between the single emitters must be strictly controlled.

High transmission sub-wavelength gratings placed in the micro-electro-mechanical system(MEMS) wavelength tunable vertical cavity surface emitting laser (VCSEL) inner cavity can improve the wavelength tuning range. In order to make the wavelength tuning range of the tunable VCSEL be largest, the transmittance of the anti-reflection sub-wavelength must be the maximum. By using rigorous coupled wave analysis (RCWA), the effects of the sub-wavelength parameters (e.g., duty cycle, period, thickness) and angle of incidence on the transmission were analyzed, and the optimum parameters and angle of incidence were gotten. Either TE or TM polarization has the optimum duty cycle to make its transmittance get 99.5%. The duty cycles of TE and TM polarization are 0.23 and 0.8 under the conditions of this paper. The effect of the grating thickness on the transmittance is periodic variation. The period of TE and TM polarization are 150 nm and 300 nm, respectively. For fixed grating parameters, the transmittance can be maximum only when the incidence angle of the light source is 0°, no matter TE or TM polarization. From equivalent medium theory (EMT), it is found that the grating period has no influence on the grating transmittance. At last, the transmittance was calculated when the grating thickness and duty cycle changed together, and the optimum grating parameters were gotten.

Electron beam irradiation experiments were taken on the domestic CMOS image sensors, the irradiation effect and damage mechanism of the devices were analyzed. By using off-line measuring method before and after irradiation and in the process of annealing, the parameters such as dark signal, saturated voltage, spectral response characteristics were measured. The experiment results show that the non-uniformity of dark signal and dark current increase with the increase of irradiation dose and high temperature annealing time. The saturation voltages reduce significantly under the electron beam irradiation and recover in the process of high temperature annealing. There is no significant change for spectral response characteristics before and after the irradiation. The changes of the dark current, saturation voltage are due to the broadening of the photodiode depletion layer caused by irradiation-induced oxide trapped charge and the increase of recombination centers caused by irradiation-induced interface states.

Based on the principle of organic electroluminescence (EL), models of carrier injection delay time and EL the delay time were developed. The results show that the EL delay time is significantly related to the light-emitting area, the thickness of organic layer and the applied voltage. By preparing organic LED devices with different areas, it is found that the light emission delay time is shorter when the device area is smaller. Furthermore, excited by high-speed signals, the OLED device with an area of 0.01 mm² is effective under the excitation with a frequency of 1 000 Mbit/s, leading to an energy utilization rate of 47.7%.

OTFT devices were fabricated through inkjet printing active layer on SiO₂ dielectric. To improve the device performance, SiO₂ layer was modified with octadecyltrichlorosilane (OTS) or a thin layer of Al₂O₃ (1 nm) by atomic layer deposition. The surface morphology, contact angle of PDVT-8 solution on the dielectric layer, and the crystalline of the inkjet printing active layers were examined. The surface morphology of the modified dielectric layer is slightly various with SiO₂ layer, while the contact angle and crystalline of the inkjet printing active layer change significantly. For OTS-treated dielectric layer and ALD Al₂O₃-treated dielectric layer, the mobility increases 4 times and 9 times, while the on/off current ratio increases 1 order of magnitude and 4 orders of magnitude, respectively, The maximum value of mobility and the on/off current ratio are 0.35 cm²/(V·s) and 6.0×10⁶.

Highly efficient hybrid white organic light-emitting diode (WOLED) with stable emission spectrum was fabricated by using two separately monochromatic emission layers (EML). The blue emissive layer was based on 14%(mass fraction) trans-1,2-bis(6-(N,N-di-p-tolylamino)-Naphthalene-2-yl)ethene (BNE) doped in BePP₂, and the orange emissive layer was based on 1%(mass fraction) Ir(bt)₂(acac) doped in a mixed-host of 49.5%(mass fraction) NPB and 49.5%(mass fraction) BePP₂. Without the use of any outcoupling techniques, this device can achieve a power efficiency of 39 lm/W at brightness of 100 cd/m², and slightly rolls off to 27.5 lm/W at brightness of 1 000 cd/m². There is nearly no color shift with the bias voltages as the Commission Internationale de L'Eclairage (CIE) coordinates are (0.37, 0.48) and (0.37, 0.47) at 1 000 cd/m² and 10 000 cd/m², respectively. The stable emission spectrum can be contributed to the well designed ambipolar interlayer which successfully balances the exciton generation evenly on its both sides.

Electrical bistable devices utilizing three dimensional self-assembled lead selenide (PbSe) superlattices embedded between two polyvinyl pyrrolidone (PVP) layers were fabricated by using spin-coating technique. Each PbSe superlattice is a cluster with a uniform size of 50-60 nm, which consists of hundreds of PbSe nanoparticles with an average size of 5 nm. The current-voltage characteristics for the devices with an architecture of indium-tin-oxide (ITO)/PVP/PbSe superlattices/PVP/Al exhibit electrical bistabilities and memory behaviors due to the trapping, storring, and detrapping of the PbSe superlattices. The maximum ON/OFF ratio of the current bistability for the optimal device is 7×10⁴, and it is maintained for 1×10⁴ s with little degradation. The electrical bistable properties and the carrier transport mechanisms of the devices are interpreted by the conduction models based on the results of fitting the current-voltage curves.

A slot waveguide amplifier based on high concentration erbium-doped polymers, working at 1 550 nm wavelength under 1 480 nm pumping, is presented to realize high optical gains with low pump powers for the loss compensation in the silicon-based optical interconnection. The influence factors of the gain properties, such as the optical properties of the polymers, the structure sizes of the slot waveguides, and the signal and pump powers, are numerically simulated. This structure, with the nanometer scale, only needs a 1.5 mW pump to obtain a 4.5 dB gain, which exhibits promising applications in integrated optical systems. Further, multiple-layer slot structures are introduced to get higher gains, and the over-lapping integral factor of the four-layer slot waveguides is 42% larger than that of the one-layer waveguides.

In order to improve the temperature uniform in the reaction chamber of MOCVD, the two-dimensional model was established based on the vertical MOCVD reaction chamber researched by ourselves. Using the finite element method, the incentive effect of current on the reaction chamber temperature uniformity was analyzed. For purpose to improve the temperature uniformity, the change of magnetic field and graphite disk surface radial temperature were observed by changing the current intensity and frequency. It is found that the electrical parameter is proportional to the heating efficiency but inversely proportional to heating uniformity, Under the same power, the temperature uniformity decreases with the increasing of the current frequency. Reasonable electrical parameters which reflect from above, ensure both reaction temperature and temperature uniformity, is conducive to the quality of thin film growth.

A naphthalimide fluorescent probe was synthesized using 1,8-naphthalene anhydride, N,N-dimethylethanolamine and triethylene tetramine as raw materials and characterized by ¹H NMR and IR spectra. The fluorescence spectra of the fluorescent probe in ethanol/water mixed solution were measured. The influence of metal ion concentration on the fluorescence intensity was investigated, and the proposed mechanism between the probe molecule and Fe³⁺was studied. The results demonstrate that the target product shows the exclusive recognition performance to Fe³⁺ in ethanol/water mixed solution. When the concentration of Fe³⁺ is in the range of (1.87~6.53)×10^-6 g/mL, the fluorescence intensity of the probe has good linearly relationship with the concentration of Fe³⁺. The linear correlation coefficient R is 0.995 3, and the detection limit is 405.1 ng/mL.

A novel plasma photonic crystal (PPC) was obtained by varying gas pressure in Ar/air dielectric barrier discharge using two planar water electrodes. The PPC had complex square symmetrical structure, including thin plasma columns in the center of each sublattice, plasma slices around the sublattice, plasma columns at the intersection of plasma slices, and thick plasma columns on the edge. By using the optical emission spectrum method, the plasma parameters in different positions of the PPC were studied. The electron densities were compared by measuring the broadenings of Ar Ⅰ (2P₂→1S₅) spectrum line, and the molecular vibration temperatures were calculated by the spectrum line of nitrogen band of second positive system (C³Π_u→B³Π_g), respectively. It is proved that not only the thin plasma columns in the center of each sublattice, plasma slices around the sublattice, plasma columns at the intersection of plasma slices, and thick plasma columns on the edge have different plasma parameters, but also the thin plasma columns at different locations in the center of each sublattice are not the same. The descending order of the electron density is that:thin plasma columns at the four corners (A), thin plasma columns near the four sides (B), thin plasma columns near the center (C), thick plasma columns on the edge (D), plasma columns at the intersection of plasma slices (E), and plasma slices around the sublattice (F). The change rule of the molecular vibration temperature is opposite to that of the electron density. As the refractive indexes in A, B, C are all different, and show inside-out gradual change periodically, the graded-index PPC is obtained by the different plasma parameters in different locations.

Under the experimental condition, different halftone mixed pixel samples were printed out with inkjet printer. 125 groups of reflectance spectra of the samples were measured. The morphological character indices were selected and the variation of halftone sample at different component proportion was analyzed. The correlation between the morphological indexes and reflectance spectra of halftone samples is obvious. 4 chosen morphological indices are correlative. After the index whose R² is greater than 0.9(R is correlation coefficient) and confidence level is greater than 0.05 are removed, the best morphological index is chosen for different character wavelength of different primary color. The variation of different morphological indices in different wavelength is distinct. The relationship between the morphological character of primary color and the component proportion of halftone can be fitted by linear and polynomial curves, and R² is greater than 0.9.

The photonic crystal (PC) coating with low transmittance can effectively suppress the thermal radiation of high temperature target. It becomes possible to detect such camouflaged targets applying terahertz (THz) wave due to the strong penetration capability of THz radiation. The propagation characteristics of THz wave in the PC coatings proposed in the references were investigated and analyzed theoretically based on characteristic matrix method of thin-film. The propagation characteristics of THz wave with different incident angles were studied later. The results exhibit that the THz wave ranging from 0.3 to 3 THz does not locate in the band gaps of the PCs. The wave in 0.3~0.5 THz has strong penetrability to the coating, the spectral transmittance is up to 90%, and the absorptivity over the whole band keeps as low as 0.2%. In addition, the incident angle has relatively little influence on the propagation characteristic when it is less than 60°. With the angle further increasing, the transmittance decreases and the reflectivity is diametrical. The final results demonstrate the feasibility to detect and recognize the targets covered with PC infrared stealth coatings by applying THz wave, and THz radar is promising for use to make up for the deficiency of the infrared detection system.

A relationship equation between the target chromaticity coordinate and the duty cycle based on the principle of RGBW color mixing and pulse width modulation (PWM) was established. The multi-constraint optimization simulation of the luminous flux and the general color index of mixed light based on genetic algorithm was carried out on Matlab program by selecting thirteen groups of target color temperature in the temperature range from 3 571 to 11 082 K, which was further verified by the experiments. The results show that the luminous flux can reach up to 166.062 lm under the maximum optimization of luminous flux, while R_a can reach up to 88.3 under the maximum optimization of general color index. Finally, the genetic algorithm was used to simultaneously optimize the luminous flux and general color index. It can ensure that the mixed light has high luminous flux to satisfy the demand of the current lighting manufacturing while the general color index exceeds 82.