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As integral imaging has narrower viewing angles for three-dimensional reconstruction images,it can not be widely applied in three-dimensional display.To enhance the viewing angles of integral imaging,this paper develops a new three-dimensional integral imaging system with a larger view angle based on the multi-level projection technology.The system projects the element image array with different levels in parallel based on multi-projectors and obtains a construction image with a large viewing angle by three dimensional reconstruction.As compared with the conventional method with multi-axles,the proposed method has the advantages on its simply structure without other field lenses and stable system no vibration and noises.Furthermore,it is suitable for the large-scale integral imaging system.The optical experiment shows that the viewing angle of proposed integral imaging system with multi-projectors is ±35°,which is 2.92 times that of the conventional integral imaging system and enhances the viewing angle greatly.

The sensitivity and dynamic range are main performance parameters of a Surface Plasmon Resonance(SPR) biosensor with phase modulation.In this paper,the main effect factors on sensitivity and dynamic range of the sensor were analyzed,and the influence of nonlinear change of phase difference on the results of real-time monitoring biological reaction was analyzed.A high resolution SPR system based on a Mach-Zehnder configuration was set up.The phase difference curves of a series gold membrane thicknesses and incident angles were simulated by matlab software,and the effect of several factors on the resolution and dynamic range were evaluated.In addition,the real-time monitoring of binding reaction between Bovine Serum Albumin(BSA) and BSA antibodies was also demonstrated.Obtainecl results show that the influence of membrane thickness is significant and nonlinear,but the incident angle shows little effect on the resolution and dynamic range.The influence of narrow dynamic range on biology reaction measurement can be minimized by optimizing some parameters,such as membrane thickness,incident angle and reactants concentration.Experimental results show that the sensitivity and dynamic range can be optimized by adjusting gold membrane thicknesses.This paper analyzed several influence factors of the sensitivity and dynamic range of phase modulation SPR biosensors.For a light source with 633 nm wavelength,the most optimal membrane thickness is 48 nm when the reaction between BSA and its antibody is measured.In this situation,the dynamic range is 0.013 6RIU and the sensitivity is 6.67×10-7RIU/0.01°.

On the basis of the principle of integral imaging and the relation between camera array and display lens array,a pick-up system using a camera array for three-dimensional integral imaging was analyzed according to the geometric imaging theory and the ray tracing method,and the dependence of main recording parameters on display characteristics of integral imaging was obtained.A parameter design method for elemental images was proposed according to the display specifications and a pick-up system was designed by the proposed method in a pick-up distance of 49.6 cm and a camera space of 25 mm.The experimental results demonstrate that the pick-up system using the camera array can record the 3D information for a scene completely and the 3D display characteristics reach to the design requirements.Furthermore,the relationship between the pick-up parameters of the camera array and the display characters coincides with theoretical analysis,which verifies the display performance of designed system and the feasibility of the proposed method as well.The system can generate elemental images with large scenes and high resolution for mismatched full optical integral imaging systems.

Three-dimensional scene is the mirror image of recording scene in a traditional integral imaging system.However,when a camera array is employed to capture elemental images,it can not be reconstructed correctly becaused of the mismatch between the parameters of lens array and the parameters of camera array.In order to rebuild a new relationship between the reconstructed image distance and the parameters of elemental images,a new method by using the Space of Corresponding Image Points(SCIP) to calculate the reconstructed image distance is proposed.In this method,the SCIP is a function of the object distance of scene,the focal length of camera and other parameters.It is equivalent to the lens array in the process of image reconstruction.By transforming the SCIP matched with the parameters of lens array,the scene with different reconstracted image distances can be reconstructed exactly.By experiments,this paper verifies that different SCIPs can result in different reconstructed image distances theoretically and experimentally.

As the integral imaging three-dimensional(3D) display technology is limited by the depth of field in a reconstructed image,it can not be widely used in the fields of 3D display.Therefore,this paper proposes a method to enhance the depth of field in a projection-type integral imaging system based on the angle control.To enhance the depth of field,an additional lens is used to control the diverging angle of every pixel in the elemental image array.Contrast to the conventional method with multi-layers,the proposed method has advantages in simpler systems,higher efficiency and lower requests for display devices.Experimental results show that the depth of field is 6.4 times that of original one when the diverging angle is 1.79°.And as compared to the conventional method with an enhancement of 4 times depth of field,the proposed method has increased by 60% in efficiency.These results demonstrate that the proposed method gives a new way to enhance the image quality for integral imaging display systems.

The quantitative analysis of spectral domain optical coherence tomography was researched to acquiring interior information of biological tissues.The single-scattering model,confocal single-scattering model and multiple-scattering model were presented and discussed.An average A-scan algorithm and a nonlinear curve-fitting method were employed to explore the scattering features of IntralipidTM.Experiments show that the relation of scattering coefficients and concentrations is linear in concentrations from 1% to 10% of IntralipidTM.Fourthermore,it confirm that the confocal single-scattering model is suitable to our spectral domain optical coherence tomography.In addition,the confocal model was used to study fresh rat liver with a scattering coefficient λ0 of 8.9 mm-1 at 1 550 nm.Obtained results demonstrate that the quantitative spectral domain optical coherence tomography can be used for clinical diagnosis of diseases in a great potential.

By taking optical acquiring 3D objects with a lens array for an example,a method to obtain the optimal pick-up distance was proposed to reduce the elemental image overlap and the crosstalk in reconstructed three-dimensional images for 3D integral imaging and display technology.By analyzing the effective imaging rates of object points and the image point utilization of objects with various sizes at different pick-up distances,the optimal pick-up distance was achieved.Compared with conventional methods for a specific integral imaging system,the product of the effective imaging rates of object points and image point utilization has increased at the optimal pick-up distance and the maximum one can increased by 34 times.Optical experimental results show that the reconstructed images has full 3D information and wealth detail,which verifies the feasibility of the proposed method.Moreover,the method is suitable for both the lens array and the camera array to acquire 3D information.

To obtain ideal 3D dimensional displays with crosstalk reduction,this paper researches how to arrange the elemental image and to match it with the reconstructed micro-lens array when a three dimensional scene is recorded by a camera array.The principle of integral imaging is analyzed and design parameters such as the pitch of elemental image,pitch and the focal length of the micro-lens array are studied.On the basis of the analysis,the optimum design parameters are given.Two conditions are discussed respectively when the elemental images are placed within and beyond the focal point of the micro-lenses.When the elemental images are placed at the focal plane,a virtual and real reconstructed image can be obtained simultaneously.The imaging quality is compared in above conditions.It is noted that the less crosstalk and larger depth of the focus can be seen while the elemental images are placed at the focal plane.The conclusion can provide a direction for arranging images and 3D reconstruction when the camera is used to capture a larger scene.

On the basis of the concept of Spectral Domain Optical Coherence Tomography(SDOCT),a fiber type SDOCT system which is easy to integration was developed.The system shows its longitudinal resolution in 7.3 μm,lateral resolution in 9.5 μm and offers the imaging depth to be 3.14 mm in air.The system obtains the sample deeply by a interferometer,which achieves the dada collection fast.The organizational features of salivary glands were researched by the above system,and the OCT images for the parotid glands were compared with that of the pathological section.Results show that the system proposed can provide a direction for the early diagnosis and the non-harmful examination of the oral cavity tissue.