Bionic optics
For traditional flow cytometry, it is necessary to solve the problem of cell subcellular morphological recognition and the change of cell activity by fluorescence staining. According to the physical characteristics of lymphocytes and eosinophils, the model of particle-free eccentric sphere cells and the dual-core cell were established. Afterwards, based on the simulation experiment software of light scattering theory, a simulation experimental light path which can receive both forward and backward scattered spectra of cells was designed. The scattering distribution of the cell model was obtained, and the relationship between the light intensity and the incident wavelength was established under the relative refractive index of the nucleus and cytoplasm. Through the analysis of the characteristics of the forward and backward scattered light spectra, it was found that the forward scattered light signal was set as X-axis, the cell backward scattered light signal was set as Y axis, lymphocytes and eosinophils had distinct classification characteristics so that a classification method for lymphocytes and eosinophils was proposed. Finally, the method of classifying and counting in this paper has some potential application value for designing all optical, non-invasive and unmarked blood cell analyzer.
2018, 47(3): 310001.
doi: 10.3788/IRLA201847.0310001
In order to realize the error analysis of the bionic compound eye imaging system, a method of error analysis was introduced. The mathematical model was established. By finding the conversion matrix of the coordinate system, the transformation between the geodetic coordinate and the coordinate system with the subeye as the original point was realized. The equation of quantity relation between the rotation angle and the parameters of the bionic compound eye, that is, the measurement equation of the system, was derived. By using the method of function error, the measurement equation was transformed into an error function equation, and the error analysis was carried out. The experiment was set up, and the experimental data were collected. The feasibility of the analysis method was verified by comparing the calculated values with the actual measurement data. Theory calculated rotation angle systematic error is 3'14. Actual measured rotation angle error is 3'15. The calculated value of the theory is in agreement with the actual measured value, which proves that the error analysis method is feasible.
2018, 47(3): 310002.
doi: 10.3788/IRLA201847.0310002
As a special transflective focusing element, the lobster eye lens has important application value in the field of high energy such as X-ray, and in the visible light, infrared band has potential applications. Focused on improving the imaging quality of the lobster eye lens, the diffraction interference factor and the diffraction field of the variable periodic glare grating were discussed theoretically. The inner wall of the lobster eye channel was micro-formed by the variable periodic blazed gratings, and simulating the structure of one-dimensional lobster eye had been micro-formed. The simulation results show that the focal length is 100 mm, effective semi aperture 95 mm bores the existing structure in coke. The dispersion spot diameter at focal plane is reduced from 10 mm to 1 mm, the energy concentration increases from 75% to 89.62%, and the spot diameter and the concentration of light energy at the focal plane at different incident altitudes are both increased.
2017, 46(9): 910001.
doi: 10.3788/IRLA201746.0910001
Aiming at the single character of target image acquisition in the traditional bionic vision system, multispectral visual image processing method based on adaptive regulation of humanoid eye was proposed. Firstly, the improved automatic focusing algorithm was used to collect the high resolution image of visible light and the low resolution image of near-infrared light. In the multispectral imaging system, there were different problems of visible and near-infrared image resolution under fixed focal length due to different refractive index of spectral prism. The improved two-generation wavelet transform was adopted to enhance the image contrast and improve the visual effect. Finally, the performance of automatic focus algorithm and image enhancement algorithm was verified by using a multi-spectral experimental device based on liquid zoom lens. The experimental results indicate that the average time of effective auto focusing system is 756 ms, and the gray variance function value increases by 79.4% after near infrared image enhancement, which solves the problem of low contrast and fuzzy details and realizes adaptive regulation.
2017, 46(9): 910002.
doi: 10.3788/IRLA201746.0910002
The finite difference time domain(FDTD) method was adopted for simulation of the conical bionic moth-eye micro-nano structure on silicon substrate in middle infrared band(3-5 m). A parameter-optimized combination of the micro-nano structure which was of low reflection was obtained by analyzing the parameters of the micro-nano structure, such as fill factor, period and etching depth. In order to guide the actual processing better, tolerance analysis of different parameters was carried out. The binary exposure and reactive ion etching technology were applied to fabricate the conical bionic moth-eye micro structure on silicon substrate in processing. The surface topography of the micro structure was acquired by thermal field emission scanning electron microscopy. The test of the silicon wafer with single-sided micro structure polishing by the infrared imaging spectrometer demonstrates that the reflectivity of the bionic moth-eye micro structure vibrates approximately 5% in middle infrared band.
2017, 46(10): 1033001.
doi: 10.3788/IRLA201792.1033001
In the field of biological medicine and clinical medicine, the diagnosis and treatment of many diseases almost rely on the identification of cell morphology. Different cells have different shape which would lead to the change of the light propagation characteristics among biological tissues. What's more, it affects the light scattering properties of cells. At present, the theory of dynamic light scattering is the optimal way to dynamically identify the distribution of the size and the shape which related to the cell. Cells are mainly composed of cytoplasm, nucleus and mitochondria. Therefore, analyzing their optical properties have great significance for optical diagnostic and treatment. Experiments were designed to obtain the light scattering properties of lung cancer cells and Polystyrene microspheres which contained cytoplasm, nucleus and mitochondria. The models of cytoplasm were built with finite different time domain(FDTD) algorithm to simulate the light scattering properties. The light scattering properties of lung cancer cells demonstrate that mitochondria make a contribution to forward scattering (0-20) and backward scattering (160-180), nucleus make a big difference to side scattering (80-100), cytoplasm have an effect on any angle. The result of the simulation testified that the experimental results are correct.
