Design And Experiment Of Biological Micro-imaging Platform With Forward And Upward Viewing Angles

Cell is the basic structural unit of fruit and vegetable plants.Obtaining the basic size and morphological information of cell has important scientific value and practical significance for botany research.Most cells are irregular three-dimensional structures.It is difficult to understand their three-dimensional size and three-dimensional shape characteristics only from the two-dimensional plane image of cells.The existing biological microscope can only observe the single-cell samples of fruits and vegetables from a single perspective to obtain the top view or bottom view of the samples.Although some microscopes can obtain the three-dimensional morphology of the local surface of the cells in a limited range,they cannot obtain the cell size and morphology information of the main view angle orthogonal to the top view or bottom view.In order to obtain the three-dimensional size and morphological characteristics of fruit and vegetable cells,this paper carried out the design and experiment of biological microscope platform with positive and upward view for fruit and vegetable cells.The specific work is as follows:(1)Basic experimental study on mechanical isolation of single cells from fruits and vegetables.Because the mechanical separation method of single cells in fruits and vegetables has the characteristics of simple operation and small wall damage,nine different kinds of fruits were selected,and the single cells were separated and evacuated from the pulp in different areas by mechanical comb and brush.The geometric parameters,damage morphology and mechanical separation integrity rate of pulp cells in each area were counted,and the difficulty of mechanical separation of fruit cells in different fruits was analyzed,it provides an objective basis for the structural design and scope of application of the biological microscope platform in the later stage.The results showed that tomato,honeydew melon and pitaya were suitable for mechanical separation according to the integrity of single cells and the folding degree of cell surface.The average particle size of single cell of tomato,honeydew melon and pitaya separated by mechanical separation method was 511±139μm、365±94μm、132±35μm respectively.The maximum projection area of single cell is 0.62 mm~2,which provides a reference basis for determining the structural size design of micro platform.(2)The overall design and structural force simulation of biological microscope platform with forward and upward viewing angles.The biological microscope platform with forward and upward viewing angles mainly includes a microscope component,a light source component,a living single-cell stage,a three-axis micro mobile device and a platform bearing seat.The microscope component includes a lens arm,an objective lens converter,an eyepiece base,an eyepiece barrel,an objective lens and an electronic eyepiece;The light source assembly includes lamp post,upper light source,side light source,lamp switch knob,lamp brightness adjustment panel,electric socket,lamp post upper cover,lamp post side cover;The living single cell stage comprises a fixed column,a reflecting prism and a sample glass tank;The bearing seat comprises a three-axis micro moving device,a titanium alloy plate,an aluminum alloy profile frame,a positioning angle iron and a edging strip.After the mirror inspection component obtains the main view of the sample in the positive viewing angle direction,adjust the position of the mirror inspection component and light source component required for the overhead viewing angle observation through the translation in the three-axis direction,and obtain the bottom view of the sample by using the 45°reflection prism fixed on the stage.In order to verify the stiffness and stability of the whole machine,the static finite element analysis of the force under the installation condition of the mirror arm and bearing seat parts is carried out through ABAQUS software.Secondly,the mechanical simulation of the moving condition of the whole machine is carried out.The results show that the platform meets the requirements of strength,stiffness and reliability.(3)Trial production and single cell observation verification test of biological microscope platform with forward and upward viewing angles.The mirror arm,lamp column,upper cover of lamp column,side cover of lamp column,fixed column and sample glass slot of object stage,titanium alloy plate,aluminum alloy profile frame and positioning angle iron of bearing seat are trial produced.The electronic eyepiece,objective lens,light source,three-axis micro moving device,objective lens converter,eyepiece base,eyepiece barrel,lamp switch knob,lamp brightness adjustment panel,electric socket,reflection prism and edge wrapping strip are selected,Then,the prototype of the biological microscope platform with forward and upward viewing angles is completed,and the performance indexes such as the resolution,actual field of view area and fine-tuning range of the prototype are measured.In order to further verify the observation effect of the prototype,the observation experiment of tomato single cell positive and upward viewing angle is carried out.The results show that the biological microscope platform prototype can obtain the positive and upward viewing angle images of single cells,the shape and contour of cells are clear,and the three-dimensional geometric dimensions of single cells can be extracted from the main and upward images.