By using the Wigner distribution function and the generalized Huygens-Fresnel principle, an analytical formula, which is independent on specific spatial power spectrum of the refractive index fluctuations of atmosphere, for beam width of partially coherent beams propagating through atmospheric turbulence along a slant path is derived. Then, taking the partially coherent flat-topped (PCFT) beams as a typical example, the analytical formula for beam width spreading of PCFT beams propagating through atmospheric turbulence along a slant path is given. Consequently, numerical calculations and analysis are carried out by considering the vertical distribution models of atmospheric structure constant of refractive index in Hefei, and the results for a slant path are compared with those for a horizontal path. Research results demonstrate that the beam width is not only related to the beam order, the degree of spatial coherence, the waist radius, the intensity of turbulence and the propagation distance but also closely to the zenith angle. With the higher beam order, the worse spatial coherence of the beam and the smaller zenith angle, the spreading of beam width is less affected by the turbulence. When the zenith angle is less than 60°, the influence of the atmospheric turbulence to the beam width along the slant path is much smaller than that along the horizontal path.

A method for capturing the solar shape and intensity on occurrence of solar occultation is proposed, and a numerical simulation model is established. The solar shape and intensity matrix without atmospheric refraction effects is taken as a reference; the atmospheric bending angle at any position of solar image surface produced by atmospheric refraction is inversely calculated through the Abel integral formula and the vertical distribution data of refractive index. Then the displacement occurred by the occultation state is obtained. Based on the reference image surface, the shape and intensity matrix of the solar image surface after the occultation state can be obtained by geometric calculation. The numerical results indicate that the model can simulate the solar shape and intensity in different orbital positions and any tangent point. Solar shape and intensity at the tangent points from 5 km to 60 km are simulated when the height of the satellite orbit is 600 km, and the distribution map of solar intensity is obtained. This model is of higher reference value for realizing the solar simulator which can comparatively truly reflect solar shape and intensity in application in such fields like measuring and calibration of posture parts of satellite, remote sensing technology, material measurement and so on.

Energy losses on target caused by boresight and jitter are two fundamental pointing errors for a laser pointing system. The characteristics of return photons reflected from an intended target in a laser pointing system are studied and a laboratory device is set up. With the hill-climbing method, a closed-loop laser pointing is realized. Furthermore, the accuracy of this technology is analyzed with different jitters, and effect of jitter on real-time pointing is discussed. The experimental results demonstrate that, the performance of hill-climbing method is still excellent. Moreover, with the increasing of jitter, the sample size of return photons increases, and the pointing precision decreases.

The thickness of flow field around the platform is defined based on aero-optical effect, the relationship between the thickness of flow field around the platform and the characteristic time of the aero-optic effect for the mean flow is investigated, and the rough estimation formula of characteristic time is given. Using large computational fluid dynamics software (SAED), the change of airborne optical flow field around the platform with respect to time and the thickness of flow field is computed, and change rule of aero-optic effect for the mean flow is researched. The calculation results verify the reliability of the rough estimation formula. It is shown that characteristic time of the aero-optic effect for the mean flow field is proportional to the ratio between thickness of flow field and the plane speed, which is in agreement with that of turbulence effect. In the given model, characteristic time is about 5 ms, and the characteristic frequency is less than 300 Hz. The root mean square of optical-path difference induced by the aero-optic effect for the mean flow field varies around a mean value with time. The ratio of variance to mean value is about 8%.

Theoretical investigations of the spatio-temporal statistical properties of arrival angle of a spherical wavefront perturbed by atmospheric turbulence are presented. The motivation is to evaluate the practicality of a high accuracy and high bandwidth active alignment for a ring segmented telescope used an optical tip measurement. The effect of finite wavefront outer scale is considered for exploring the spatial coherence of arrival angle. The temporal cross-spectrum of arrival angle is also calculated for studying the temporal coherence. The mean square of measurement error for a single short-exposure is calculated numerically. While, the magnitude of suppressing the error by time integration is discussed. The control bandwidth is calculated for an accuracy requirement of 0.01″ in some different cases of turbulence environment.

The modulation transfer function (MTF) of an electro-optical device describes the image quality in terms of contrast as a function of spatial frequency, which is a much better way to evaluate a device. With the development of electro-optical devices, MTF becomes a popular technique in device evaluation. A system to measure the MTF of near infrared InGaAs linear focal plane arrays is built and an all-reflective Offner relay is used to image the slit onto the measured device. The Offner relay consists of two coaxial spherical mirrors, operating as a 11 imager. At the working wavelength of 1.7 μm, the Offner relay shows a nearly diffraction limited performance over an 8 mm×30 mm field, and the measured MTF at 20 lp/mm is above 0.8 everywhere in the field. Using this system, the MTF of an 8×1 InGaAs linear focal plane array (FPA), of which the nominal pixel size is 100 μm×100 μm is successfully measured. The result shows that the ratio of the standard deviation to the average of 6 repeated tests is below 2% within the cutoff frequency of 10 lp/mm. The relative uncertainty of the MTF measurement of the 8×1 linear FPA is below 4.7%.

When measuring the modulation transfer function (MTF) of CCD camera with rectangle target, the test value of MTF is less than the actual value due to the initial position error and the initial angle error between the target and pixels of CCD. With the definition of MTF, the luminance distribution of CCD pixels is deduced and the relationship between MTF and the initial errors is given. The results with initial position and angle errors are analyzed. The formula of initial angle error is deduced by using the luminance of pixels and the result is verified by simulation.

The angular selectivity of transmitting volume Bragg grating (TVBG) is analyzed based on Kogelnik′s coupled-wave theory. The TVBG with a period of 1 μm is prepared in photo-thermo-refractive (PTR) glass with wave-front splitting interference method and two-step heat treatment process. The diffraction efficiency of the TVBG is up to 91.1% The angular selectivity of the TVBG is studied by use of divergent laser beams. The experimental results show that the TVBG has a good selectivity and can be used in angular filtering, which can suppress the medium and high spatial frequency modulation and improve the near-field uniformity of laser beams.

Vector diffraction model of photon sieves with different polarized illumination is built based on angular spectrum representation. Simulations are carried out to analyze the intensity of photon sieves, focal spot when polarizations of incident planar beams are linear, radial and tangent, respectively. Result shows that the polarization property of incident beams makes huge influence on the focal spot of photon sieves with high numerical aperture. With linearly polarized beams, the focal spot extends in the polarized direction. By using tangent polarization, there is a dark hole in the center of the focal spot. The focal spot of radially polarized beam has a form of a circle and the focus is deeper. In laser lithography systems and imaging systems, resolution power can be improved by using radially polarized beam as the incident beam of photon sieves.

Based on laser focused Cr atom beam deposition, the simulations of effect of substrate diffraction on evolution of the atom wave-packet probability density in the focused laser standing wave are done with scalar optical diffraction theory. The results show that such effect will vary with parameter b0 which stands for the distance between laser axis and substrate surface which is used for deposition. Compared with non-diffraction, the central value of the probability density distribution of the atom wave packet at the focal plane will be increased and its FWHM will be reduced by substrate diffraction. When b0=－0.2w0, the focal plane of the atom wave packet coincides with substrate surface, and the probability density distribution of the atom wave packet has central value of 1.26 with FWHM of 5.62 nm under diffraction, which are 1.1 times and 0.94 times of that without diffraction, respectively.

Based on the theory of core diameter mismatch, a kind of fiber-optic sensor composed of a multimode fiber-single mode fiber-multimode fiber (MSM) structure and a fiber Bragg grating (FBG) is proposed for simultaneous measurement of temperature and strain. Due to their different response sensitivities to temperature and strain, the temperature and strain are measured simultaneously. The experimental results show that the temperature sensitivities of the MSM structure and FBG are 0.091 nm/℃ and 0.0102 nm/℃ within the range of 20 ℃~80 ℃, respectively. The strain sensitivities are -0.0013 nm/με and 0.0012 nm/με within the range of 0~650 με, respectively. Using the sensitive matrix, simultaneous measurement of temperature and strain is realized. The maximum measurement errors of temperature and strain are ±0.2 ℃ and ±8.25 με, respectively. With high sensitivity, simple structure, immunity to electromagnetic interferences and a good linearity of the experimental results, the structure has an excellent application prospect in engineering field.

After comparing the traditional LiNbO3 Mach-Zehnder electro-optic modulator bias control techniques, a novel bias control method based on fast Fourier transformation (FFT) algorithm and the harmonic response feedback of a low frequency dither tone is proposed. Using this technique, a precise optoelectronics bias control system is realized to lock the modulator at an arbitrary point within its transfer function. This bias control technique is found to be independent on the optical input power and the insertion loss of modulator. Moreover, the proportion integration differention (PID) control method is used to optimize parameters and achieve a locking accuracy better than 0.5°. In addition, this bias control system is also verified experimentally to set and lock the modulator at an arbitrary bias point. Those results are helpful to stabilize the LiNbO3 Mach-Zehnder modulator at the optimal operating point and achieve an ultra-high speed, long haul optical fiber communication system.

In the experiments of laser signal transport in rain medium, it is obvious that the transmission in heavy rain is bigger than that in light rain. This shows that the attenuation of light signal in light rain is bigger than that in heavy rain. The transmission attenuation of wireless laser communication in rain is noticeable. According to the theory of Mie and Weibull raindrop spectrum, the effects of the particle scales on laser scattering and attenuation efficiency factor are analyzed, and the attenuation formula of the light wave of a single particle is deduced. The definite equations between the attenuation and the rainfall ratio are obtained. The result shows that scattering intensity of particle in heavy rain is bigger than that in light rain in forward direction, and the forward scattering intensity increases. When laser signal transmits through rain, attenuation coefficient in light rain is big, while it is small in moderate rain and heavy rain, and increases in rainstorm. This result coincides with the facts. Attenuation characteristic of laser in rain provides theoretical basis for laser applied in the communication system working in the rain.

A type of fiber optic hydrophone used in thin line towed array is presented. The fiber optic hydrophone, with a diameter of 13 mm, based on air-backed push-pull double armed symmetrical compensated structure is developed. Moreover, the working principle of the fiber optic hydrophone is introduced, and an optimized design structure of the fiber optic hydrophone is proposed. In the case of small diameter of the fiber optic hydrophone, the higher acoustic-pressure sensitivity is ensured, and the lower acceleration sensitivity is obtained simultaneously. Over the frequency ranging from 80 Hz to 2500 Hz, the average acoustic-pressure sensitivity of the fiber optic hydrophone is －142.5 dB with undulation of 0.8 dB, while the acceleration sensitivity is less than -20 dB. Experimental results show that the fiber optic hydrophone can well meet requirements for the use of thin line towed arrays.

The lateral and on-axis diffractive intensity distributions of an axicon lens illuminated by the monochromatic and quasi-monochromatic Gaussian beams are numerically calculated and discussed by using the angular spectrum method. Also, the on-axis diffractive intensity distribution of the axicon illuminated by uniform monochromatic plane wave is given. Unlike the well-known Fresnel diffraction integral, the propagation theory of angular spectrum defers to the more rigorous Helmholtz scalar wave equation with fewer approximation, resulting in more accurate results. The results of numerical calculation show that the intensity distribution of diffractive field in the rhombic region determined by the overlap of light rays has the characteristics of diffraction-free Bessel beam. The intensity on the optical axis changes in a fluctuating way which shows direct correlations with the lateral intensity distribution of the incident waves. In the quasi-monochromatic case, the contrast of Bessel fringes and the degree of fluctuation of on-axis intensity tends to decrease slightly, depending on the bandwidth of incident beam, while the intensity distribution keeps the same form as the monochromatic case.

The S transform is one of the time-frequency analysis techniques which combines the advantages of both the short-time Fourier transform and wavelet transform. The one-dimensional S transform has been successfully used in fringe phase demodulation based on structured light projection. The two-dimensional (2D) S transform is able to carry out the time-frequency analysis for images in two directions, which is better than one-dimensional (1D) S transform. The 2D S transform based on the structured light projection method is introduced to the three-dimensional (3D) optical measurement for completing S transform fringe phase demodulation theory. This work studies the theory and application of the 2D S transform in fringe phase demodulation and gives a detailed theoretical analysis. Furthermore, a comparison between the 2D S transform and the 1D S transform is carried out in fringe phase demodulation. The comparison result shows that the 2D S transform will achieve a higher accuracy than 1D S transform in extracting the phase distribution of the fringe patterns, even when the fringe patterns are seriously polluted by noises. Both the computer simulations and experiments verify that the 2D S transform outperforms the 1D S transform in the fringe analysis.

The spot flux-density distribution on the focal plane of linear Fresnel reflecting (LFR) concentrators is calculated with Matlab program by the ray-tracing method, with the shape of the sun, cosine loss, shading and blocking loss, taken into account in the process. Three-dimensional optical geometric model is established and the spot flux-density distribution is calculated with Matlab program. The model is demonstrated and justified by comparing simulation results of this Matlab program with that of SolTrace software developed by the U.S. National Renewable Energy Laboratory (NREL). The effects of different mirror shapes for LFR are also compared in order to obtain the higher efficiency of concentrator field.

The concentrating characteristics with the glass thickness of reflector of the solar parabolic trough system are studied by theoretical analysis, simulation, and experiments. The results show that the thicker glass of the reflector and the farther distance of the incident light from the optical axis, the bigger both ΔX and ΔY are. The theoretical analysis has been done for the solar parabolic trough system whose focal length is 1200 mm, and the refractive index of glass of reflector is 1.6. For 1-mm thickness glass of reflector, when the distance from the optical axis of the incident light is 200 mm and 2000 mm respectively, ΔX is 0.03 mm and 1.69 mm respectively, ΔY is 0.19 mm and 0.31 mm respectively. For 5-mm thickness glass of reflector, when the distance from the optical axis of the incident light still is 2000 mm, ΔX is 8.41 mm, and ΔY is 1.55 mm. The theoretical analysis is consistent with TracePro simulation and experiments. The research can provide references to further design of solar parabolic trough system.

The dynamics of the image quality reconstructed from holographic photopolymer is experimentally investigated. In experiments, the intensity and quality of reconstructed images are monitored during dark enhancement and uniform post-exposure. The quality of reconstructed images is quantitatively evaluated based on the loss of signal-to-noise ratio. The experimental results show that the intensity and quality of reconstructed images suffers from non-monotonic changes during dark enhancement and uniform post-exposure, that is, increases at first, but decreases later from the highest value. These experimental results can be explained by the formation and development of noise gratings. The tolerance of image quality on uniform post-exposure and dark enhancement is evaluated based on the characteristic time, at which the signal-to-noise ratio of reconstructed images decreases a half of the original value. The experimental data show that during the characteristic time, both of quality and intensity of reconstructed images are acceptable. In multiplexed holographic storage, the dynamics of image quality should be considered in order to ensure uniform diffraction efficiency and good quality to all holograms.

Based on the Shannon sampling theory and Fourier transform analysis, analysis on the effects of non-synchronous sampling on the reconstructed image of digital hologram is given by the simulation experiment of digital holographic grating. The results indicate that the phenomena of low frequency modulation of the transmission function will be more obvious with the increase of grating′s spatial frequency; the extent of spectral leakage is determined by the deviation of non-synchronous sampling, but has nothing to do with the spatial frequency of the holographic grating itself. Finally, the experiment of digital hologram apodization using the Tukey window function shows that the apodization method can suppress the fluctuation of reconstructed wave front caused by the spectral leakage.

On the research of evaluating optical camouflage ground targets, a method using tolerance nearness sets to evaluate ground targets′ camouflage effect is proposed, according to the characteristics of the camouflage images. The targets and backgrounds are extracted from these images, which seen as different sets in tolerance space, and divided into numbers of sub-images. Several features such as statistics, color and texture characteristics are extracted from every sub-image and all of tolerance nearness class in background and object sets are calculated. Nearness measure (tNM) is used to evaluate camouflage effect and compared with Hausdorff distance (tHD). The results show that tolerance nearness sets method can well replace human eyes to evaluate camouflage effects and tNM is better than tHD as the evaluation index.

Fourier telescopy (FT) is a sort of high-resolution imaging technology, which integrates laser initiative imaging technology, optical synthetic aperture technology and phase close technology. The effect of frequency shifting of laser is one of the most important factors to influence imaging quality of the FT system, especially in the situation of high power, broad beam and large modulation bandwidth. Various frequency-shifting error models are proposed, the transfer function of error in system is built, the effect of which on imaging of the system is researched by simulation, error analysis results of the various models are obtained. According to the results, the image quality of the system is directly influenced by the frequency shift accuracy and stability, the value of Strehl between the inverted image with error and the theoretically inverted image is below 0.2 in some of the models. As indicated, the reasonable design of acousto-optical frequency shifter and the driver circuit is an important way to improve the imaging of the system.

Most of current palm vein recognition systems use an active light source to acquire images. The choice of light-source wavelength directly affects the definition of palm vein image and recognition performance. Typical wavelength of palm vein recognition is 760, 850, 890, 940 nm, while few works have been done on investigating which one is the optimal wavelength for palm vein recognitions. It is solved from two angles. From the angle of feature extraction, the model of palm vein image definition is established and palm vein definition of the four wavelengths is compared according to the model. From the angle of feature matching, the recognition performance of palm vein image with four wavelengths separately by three typical biological identification algorithms is compared. The experiment was done in a self-build database including 2400 palm vein images with four kinds of wavelength. The experiment result of the model and 3 algorithms show that 850 nm is the optimal wavelength. Wavelength of 850 nm achieves higher palm vein recognition performance than the other three wavelengths.

Off-axis illumination (OAI) is one of the key technologies to enhance the resolution in extremely ultraviolet lithography (EUVL). For the optimizing of OAI specifications involving shadowing effect of mask, a novel model of OAI imaging is presented. It divides the incoherent incident light into a series of parallel light beams with numerical continuous directions, imaging the mask to the wafer plane with each of these beams based on Abbe imaging principle, and finally takes the superposition of the intensities to achieve OAI exposure in EUVL. Images at various defocus planes are equivalently achieved via adding extra defocus aberration into projection system. The model facilitates the simulation of the mask shadowing effect effectively. Then adapting the sidewall angle of the developed photoresist for criterion, the optimum specifications of OAI style are obtained for the exposure of 16 nm half-pitch dense line and space under the consideration of properties of photoresist and depth of focus requirement of the projection system with numerical aperture of 0.32.

The atmosphere sounding′s principle of limb and nadir detecting modes are discoursed, and the prototype of ultraviolet (UV) annular imager with fire-new detecting modes is designed, which can gets the earth limb and nadir images of atmosphere simultaneously on the near-earth orbit. The prototype has a refraction-reflection optical system, and its spectral ranges are 285～395 nm, 305～315 nm and 350～360 nm. It can realize the image sounding with multiple azimuths by earth′s limb mode (the vertical height of the atmosphere is from 0~120 km)and 10° field of view by nadir mode, and the data received can be used to retro-deduce the spatial distribution and the dynamic state configuration of the atmospheric radiation within multiple azimuths. The performances for 310 and 355 channels of the prototype are tested. The results show that the spatial resolution and the signal-to-noise ratio are both satisfied the design requirements and it is suitable for the application of the space UV remote sensing.

According to the principle of total reflection theory and the prism coupling, the simultaneous measurement of the refractive index of the prism and waveguide refractive index of film material and thickness are measured. Highly collimated diode laser is used to enter to the boundary surface of the waveguide film inside the prism, the prism coupler M line is obtained by gradually rotating the prism or changing the angle of incidence of the prism, the lines of previous trough are waveguide mode excitation in the M line ending at the left side there is an incomplete crest, its reflected light intensity decays rapidly with the angle of incidence, which is the total reflection critical point, by this the simultaneous measurement of the parameters of the prism and the waveguide film is realized; refractive index of the prism coupler integrated planar waveguide prism and the refractive index and thickness of the polymethylmethacrylate (PMMA) polymer waveguide film are measured with this method, measured prism refractive index accuracy is ±1.9×10－4. The accuracy of the waveguide refractive index and thickness are ±6.2×10-4 μm and ±1.6×10-2 μm respectively.

In an exterior ballistic measurement system, data fusion for optical measuring equipment and radio exterior trajectory measuring system is very effective to improve the comprehensive precision of target measurement and the utilization rate of instrumentations. According to a joint positioning model with photo-electric theodolite and nearby radar, data fusion of the angular-position data obtained from theodolite and the ranging data obtained from radars will be implemented by using total differential formula and the difference of measuring station sites. It is natural to figure out the target′s azimuth and pitching angle, and then the target′s three-dimensional position in space. The main error sources of the positioning model are analyzed, as well as their influence for positioning results. The analysis results show that the joint positioning accuracy of photo-electric theodolite and radar has an advantage over the accuracy computed by single radar positioning data. The precision of the joint positioning method is within 2 m, which is an obvious expression of the high angular measurement accuracy of photo-electric theodolite and high range measurement accuracy of radar.

A surface plasmon resonance (SPR) sensor with self-adaptive structure for angle shift is presented. Combined with phase detection, a measurement system for the gas refractive index is designed. The theoretical analyses indicate that the factors which affect the response of phase detection and measurement precision are the incident angle of the laser beam, the thickness of the gold film and the nonlinearity between the phase difference of p and s polarization components of the reflected light and the refractive index of gas. The application of the self-adaptive SPR sensor reduces the measurement error by one-order of magnitude and greatly improves the sensitivity. The thickness of the gold film is designed and the error which results from the nonlinearity between the phase difference of p and s polarization components of the reflected light is evaluated as well. The comparison experiments of measuring the refractive index of air show that the accuracy of the gas refractive index measurement system reaches 10-6 order.

Gamma nonlinearity of a digital camera-projector pair leads to obvious phase measurement errors in phase measuring profilometry (PMP). Among the conventional gamma correction methods, most of them use plenty of fringe patterns to implement gamma correction, which is unsuitable for real-time measurement. Based on the Fourier spectrum analysis of an orthogonal sinusoid grating, a correction method for the evaluation of the gamma value is proposed. The evaluated gamma value is then pre-encoded into computer-generated phase-shifting fringe patterns to obtain well-sinusoidal fringe patterns, the errors of the PMP are reduced. Only one pattern is needed and the defocusing effect of the measuring system is considered in the correction. Experiments have verified the feasibility and validity of the proposed method.

The supporting way is crucial to the deformation and stress concentration of any optical elements. As the large-aperture prism is characterized with non-uniform quality, rotating and titling motion, an adjustable segment-surface support way is proposed, and its specific program is designed. This paper analyzes the motion process under this support and gets the most dangerous condition. The optimization of the supporting angle under the condition is also made by the two-step optimization method, as a result, the maximum deformation peak-to-valley (PV) value and von Mises stress value in dynamic process have respectively decreased by 7.40% and 11.45% after optimization, which validates the feasibility and rationality of the optimized support way.

The technique of transmitting spatial azimuthal information between equipments without mechanical connection is important in spaceflight, military and other fields. The precision of the traditional azimuth measurement system is low, and the measurement scale is narrow, so the traditional azimuth measurement system cannot meet the requirement of transmitting the azimuth in high precision and wide scale. The modulation wave of the traditional method is transformed, the square wave magneto-optic modulation is introduced into the azimuth measurement system, and the azimuth measurement model based on square magneto-optic modulation is established. The model of modulated signal is presented according to Malus law, and its characteristics are analyzed. The equation between azimuth and modulated signal is established according to their relationship, and the variation trend of modulated signal is used to delete the equation′s extraneous roots. The phase comparison of modulation signal and modulated signal is used to widen the azimuth measurement scale. At last the azimuth measurement model based on square wave magneto-optic modulation is acquired, realizing the transmission of azimuth between equipments without mechanical connection. Simulation results show that compared with the traditional method, the theoretical measurement precision of the new method is higher, and the measurement scale is wider, which provides a reference to measure azimuth in high precision and wide scale.

Based on the framework of the spin-flip model (SFM), the bistability performances of time-varying orthogonal optical injected vertical-cavity surface-emitting lasers (VCSEL) subject to weak optical feedback have been investigated theoretically. The results show that, for a slave VCSEL (S-VCSEL) subject to time-varying orthogonal optical injection from a master VCSEL (M-VCSEL), the introduction of weak optical feedback does not change the varied trend that hysteresis width increases with the increase of the sweeping rate of optical injection coefficient. For a fixed sweeping rate of the injection coefficient, with the increase of the feedback strength, the hysteresis width will narrow. Under the case that there exists frequency detuning Δν(=νm-νs, νm and νs are the free running frequencies of M-VCSEL and S-VCSEL, respectively) between the M-VCSEL and S-VCSEL, with the increase of Δν from negative value to positive value, the hysteresis width narrows firstly, and after reaching a minimum, widens finally. The obvious fluctuation of hysteresis width appearing in the negative frequency detuning region can be suppressed to some extent after introducing optical feedback.

A model of power limit of hundred-nanosecond single-frequency pulsed fiber lasers established, by which the maximum extractable power of ytterbium-doped silica fiber and phosphate fiber are analysed. Numerical results show that the power of Yb3+-doped silica fiber sources is limited by pump brightness, lens effect and stimulated Brillouin scattering (SBS), while, for Yb3+-doped phosphate fiber sources, melt of the core is also included. On the aspect of maximum extractable power of single-frequency pulsed laser, phosphate fiber is better than silica fiber.

The inverse problem of broadband amplification is very important in research on the properties of laser amplifier. Analytic electric polarization in the temporal domain is applied to broadband amplification in the sub-nanosecond time scale. The inverse problem of broadband amplification is studied and simulated numerically in detail by use of genetic algorithm and Gerchberg-Saxton (GS) algorithm, namely, to solve the input pulsed-laser spatial and temporal shape from the given output pulsed-laser and laser amplifier parameters. On one hand, analytic electric polarization in the temporal domain is more effective to solve broadband amplification, on the other hand hybrid intelligent algorithm greatly simplifies the inverse-problem modeling of broadband amplification, and accelerates the convergence of the solution to inverse problem.

As a ball has the advantage of contour continuity, it has been used widely in camera calibration, especially in multiple camera calibration. Using a ball as calibration target can make up for the shortages of plane target that it may distort or even disappear in the field of view when the viewpoint is large. However, when a ball is projected into the camera it is usually not a standard circle, but an ellipse. The calibration precision will be affected when the elliptic geometric center is not the same as the ball-center′s real image. There are two factors that determine the distortion: the relative size and position of the ball with the camera. The influence of the two factors are analyzed, and the distortion rules are studied by simulating ball′s imaging model. A correction model which is verified feasible and effective in experiment is established. Through the model, the ball center′s projection error can achieve subpixel precision.

The optical transmission characteristics and the photonic band gap (PBG) of the nano-film are studied which consists of silica colloidal microspheres with different sizes. Nano-colloid crystal film is self-assembled with light transmitted colloidal SiO2 microspheres on glass substrate. Bragg law is used to analyze the influence of the microspheres size on photonic band gap. In order to achieve omni-directional antireflection in the range of visible light, it is proposed to move the bandgap of colloidal crystals to the ultraviolet (UV) band by changing the size of colloidal particle. It is found that close to 0.5% average reflection can be achieved when the particle size is 112 nm, and duty ratio is 0.45. Experimental results show that the average reflectance of glass surfaces is reduced from 4.3% down to 0.7% in the wavelength range from 400 nm to 800 nm. Through controlling colloidal particle size to move the photonic bandgap position, optimizing crystal structure parameters, the antireflection in visible light band is achieved, and the utilization of visible light by the optical components is effectively improved.

It is a traditional method to take obtained far-field data as the basis of LED optical design. However, far-field measurement, which is just relatively rough measuring of LED source, cannot describe the source′s space light distribution accurately. It has become a bottleneck problem of LED optical design to obtain detailed information of LED space light distribution, that is to obtain ray set. It is the key point to achieve and to use detailed and accurate information of LED source reasonably, especially information of light source′s spatial light distribution. This paper conducts two groups of experiments on LED chip and module, and then processes and analyzes the data gained in the experiments by using the lighting analytic software. By contrasting the difference in results of two test methods, the paper stresses the importance of obtaining ray set of light source to optical design. Final result shows that ray set obtained from near-field goniophotometer measurement can offer more detailed spatial distribution information of light source for LED optical design.

To improve the light extraction efficiency (LEE) of GaN-LED with hemisphere microlens array surface structure, four kinds of waveguide materials such as GaN, ZnO, SiO2 and polystyrene are studied with finite-difference time-domain method. The simulation results are further tested by mode analysis method. The results show that the LEE can be improved when the refractive index grows higher, and the LEE of microlens array with bigger radius hemisphere is better in the subwavelength structure. The optimized model with 600 nm radius hemisphere microlens array of GaN material, with which the LEE exhibites 5.66 times enhancement than that of the planar LED, is the best output among those results. The above results are analyzed and verified by the asymmetric planar mode analysis method with equivalent refractive index. These results provide a theoretical guide on the practical design and optimization of highly efficient GaN-based LED.

With the trend of reduction in depth of focus, the control of wafer surface is becoming more and more important. The control of wafer surface in dual-stage lithography is studied. The focus detection method, which is based on the polarization modulation mechanism of dual-grating moiré fringes and its measurement principle, is introduced; then the focusing and leveling technique in dual-stage lithographic system is studied. The algorithm for defocus in exposure slit is evolved by using least square method, surface fitting with a plane and coordinate translation. The defocus-decoupling algorithm is studied in detail, which converts the defocus to movement of the piezoelectric ceramics (PZT) and prevents the shift for the center of the exposure slit. The algorithm can be used for precision of 10 nm in focusing and leveling by the simulation, which can meet the need of projection step scan lithography machine with line width less than 100 nm.

A novel microwave photonic phase shifter based on dual-parallel Mach-Zehnder modulator (DPMZM) modulation sideband filtering is proposed. Within the structure of DPMZM, one optical path with a Mach-Zehnder modulator is adjusted to be maintained at the state of optical-carrier-suppressed double-sideband modulation, and the other optical path is used to introduce an adjustable phase shift of the optical carrier by simply controlling the direct current (DC) bias voltage. The output of DPMZM passes through a fiber Bragg grating (FBG) for filtering out one first-order sideband of the modulation. A wideband photodetector is used to convert the output of FBG to electronic microwave signal of adjustable phase shift. The experimental results show that the proposed microwave photonic phase shifter based on DPMZM modulation sideband filtering has the advantage of stable transmission characteristics with small amplitude fluctuation, fast phase tuning response, wide frequency band and a phase shift greater than 360°.

The polymer waveguide electro-optic (EO) devices play a key role in improving the optical network bandwidth and capacity. A quasi-rectangle EO waveguide based on organic/inorganic hybrid material (OIHM) is designed and fabricated. SiO2 is adopted as the lower cladding. The ultraviolet photo-resist SU-8 is used as the guiding core. The chromophore of dispersed red 1 (DR1) doped OIHM is used as the EO active layer. Through optimizing the parameters including antenna power, biasing power and O2 flow rate of inductively coupled plasma (ICP) etching, SU-8 can be applied as the guide core and etching mask at the same time. By the traditional semiconductor processes, the quasi-rectangle EO waveguide device is successfully fabricated. Under this condition, the transmission loss is -3.5 dB/cm.

The interaction of two quantized fields with an atomic ensemble including N three-level V-type atoms inside a two-mode cavity is investigated. With nonadiabatic elimination, the quantum correlation properties of two output cavity fields are analyzed when the two initial input fields are in coherent states. The results show that the quantum entanglement can be generated at the zero frequency under appropriate conditions. As the cooperation parameter increases, the zero-frequency entanglement decreases, and even vanishes. However, a pair of sideband entanglement happen in the high-frequency regime, which are induced by vacuum Rabi splitting. In addition, by modifying the intensity of the quantized fields and the antisymmetric detunings, two pairs of sideband entanglement can also be obtained. These results will benefit the research of the sideband quantum correlations.

An analytical solution is developed to describe the localized surface plasmon resonance (LSPR) responses to complicated environmental refractive index of metal nanostructures with arbitrary shapes. Both local and bulk refractive index sensitivity equations with their essential influence parameters are also presented. Theoretical analysis and numerical calculation results demonstrate that the peak wavelength of the LSPR spectra for metal nanostructures increases exponentially as the analyte thickness grows, and is greatly dependent on the refractive index of analyte, receptor thickness as well as metal nanostructures shapes and materials. The bigger the refractive index of analyte, the greater the spectra response. Furthermore, a thicker receptor will induce poorer local refractive index sensitivity and a sharper shape will bring on greater bulk refractive index sensitivity. These results can be used as guidelines in fabricating high sensitive LSPR-based biochemical sensors.

For one-dimensional semitransparent medium layer with rough surface and Gaussian distribution, the transfer probability model of the spectral radiation on rough surface with shading effect considered is established with microfacet slope method. Monte Carlo method is used to simulate the radiation transfer. The reflection and refraction of spectral radiation at rough surface, absorption of medium and specular reflection on the substrate are considered along with the effects of shadowing and masking. The effects of roughness, optical thickness, refractive index and reflectivity of substrate on bi-directional reflectance distribution function (BRDF) are investigated. The results show that the change trends of reflection peak with incident angles for different rough levels of surface are different, the diffuse component increases with roughness and refractive index, and reflectivity of substrate and optical thickness change the value mainly instead of the distribution trend of BRDF.

Technology of image plane interferometric hyperspectral imaging is mainly applied in remote sensing imaging field. In order to realize spectral imaging of targets at different distances, a method of image plane interferometric hyperspectral imaging is presented. A re-imaging interferometic system is set up by inserting front-end imaging lens, relay collimating lens and transverse shear beam splitter in infinite imaging system. A separated front-end imaging lens method with choice of zoom lens or lens of different focal length is adopted to achieve spectral imaging of targets at long or short distances. The imaging system, resolution of spectrum and push-broom mode are analyzed. Experimental device is set up to detect the targets of near field indoor and far field outdoor. A microscopic spectral imaging test of biological tissue is also carried out with the device. Experimental results show that the proposed imaging method is effectively applied in hyperspectral imaging of targets at different distances.

The properties of leaky modes of the fluorescence and the amplified spontaneous emission (ASE) in the dye film with quasi-waveguide structure are theoretically and experimentally investigated. Theoretically, considering the propagation loss and dye absorption loss, the physical mechanism of leaky-modes characteristics of the fluorescence and ASE are analyzed by calculating the field intensity distributions of the leaky-modes in the dye film with quasi-waveguide structure. Experimentally, the dye films are spin coated on the prism substrate, and the spectra of fluorescence and ASE of leaky modes of the dye films with quasi-waveguide structure are measured by the prism coupling method at different wavelengths and different output angles. The results show the consistence of theoretic analysis and experimental measurement. In addition, a beam analyzer is used to obtain the intensity distribution of fluorescence and ASE of leaky modes to understand the ASE exciting characteristic in the dye film with quasi-waveguide structure. It shows the redshifts of the fluorescence peaks and the ASE peak as well as the exciting leaky modes come from the interaction of the interface reflectivity, the propagation loss and the dye absorption loss, while the interface reflectivity is the dominate factor for exciting the leaky-modes, and the dye self-absorption is the dominate factor for the redshift of fluorescence peaks and the ASE peaks.

Terahertz wire-grid polarizer and terahertz band-stop filter have been fabricated on polyimide substrate by laser inducing and non-electrolytic plating with copper. The performance of the fabricated devices is measured using a terahertz time-domain spectroscopy. Test results demonstrate that the high extinction ratio of the fabricated polarizer is better than 20 dB from 0.2 THz to 1.5 THz, and three different central frequencies are 0.41, 1.07, 1.47 THz for the Jerusalem cross band-stop filter. The experimental results are in good agreement with finite-difference time-domain simulations. The results demonstrate that the laser induced and non-electrolytic plating with copper is a simple, effective, and flexible way to fabricate terahertz devices on polyimide substrates.

In order to improve electrochromic properties of tungsten-oxide (WO3) thin films, polyethylene glycol (PEG)-doping WO3 films are prepared by peroxopolytungstic acid sol-gel method. Microstructure, optical and electrochromic properties of the films are investigated by X-ray diffraction, spectral ellipsmetry, ultraviolet-visible spectrophotometer and cyclic voltammetry, respectively. Results show that PEG-doping tungsten-oxide films contain nanocrystalline/amorphous nanostructure, which facilitate ions transport in the films. Compared to pure WO3 film, the PEG-WO3 film possesses wider spectral modulation, higher coloring efficiency, good electrochromic reversibility and cyclic stability.

The effect of line attributes, defined by ISO13660 standard for digital hardcopy imaging, on text perceptual distinctness is investigated. For lines with equivalent widths and strokes of Black Type Chinese charatescs and Times New Roman English letters with 6.5 points and 10.5 points, the line attribute parameters of their hardcopy prints are measured. And evaluations of the psychophysical distinctness on the text with a little strokes and line stripe, are carried out. Then a linear correlation model is built up between them. Experimental results indicate that the text perceptual distinctness can be linearly related to line′s contrast, raggedness, relative blurriness and line width, and always positively related to the contrast and negatively related to the raggedness and the relative blurriness. Whereas, in the case of simple strokes or strokes with large distance, there is a positive correlation between the text perceptual distinctness and line width, otherwise, negative correlation. Additionally, there is at least 1 time difference in the influence weight of each line attribute on the text perceptual distinctness.

In order to shorten the waiting time before experiment, reduce the damage caused by heat radiation and lower the influence of thermal deformation on the experiment, thermo-mechanical analysis of deflection focus system is carried out by making full use of synchrotron radiation X-ray to obtain stable and effective experimental results. Based on the main parameters of Shanghai synchrotron radiation facility (SSRF), the thermal power density distribution absorbed by deflection focus system on X-ray interference lithography (XIL) line is calculated. Then dynamic thermal equilibrium analysis is carried out under the conditions: without water cooling, with water cooling and thermal radiation. Finite element analysis is used to perform the thermo-mechanical analysis of M1, M2 in order to obtain parameters such as the time required for thermal equilibrium and the temperature gradient distribution. Results indicate that the thermal load effect on M1, M2 of deflection focus system can be weakened by indirect water cooling structure. Thermal equilibrium durations of M1, M2 get dropped substantially from 8677 s and 7850 s to 960 s and 840 s, respectively. The highest temperatures reduce from 182.73 ℃, 129.73 ℃ to 57.94 ℃, 47.29 ℃, respectively. Meanwhile, the biggest slope errors are 7.23 μrad, 9.24 μrad, respectively. The waiting time from operating to experiment is shortened, which can improve the efficiency greatly and ensure steady and effective experimental results.