What is the function of automatic continuous zoom video microscope?
Stereo microscopes are widely used in biological anatomy, microbial observation, microsurgery, mineral structure observation and industrial production. The industry is mainly used in the production, assembly, and quality inspection of fine parts such as electronics manufacturing, semiconductors, and watches. It is a necessary process equipment for some processes. Although the stereo microscope has binocular observation and continuous magnification, it has a strong sense of three-dimensionality, but it is still easy to cause fatigue to the operator. With the advent of CCD and CMOS image sensors and the continuous reduction in cost, a monocular continuous zoom video microscope has emerged. The video monocular microscope has the advantages of wide field of view, intuitive and real, simple operation, and the operator is not prone to fatigue, so it has developed rapidly. There is a tendency to replace stereo microscopes for binocular observation in the production line.
1.1 Working principle of continuous zoom video microscope
The continuous variable magnification video microscope (hereinafter referred to as the video microscope) began with a binocular observation stereo microscope. Its optical system is mainly composed of three parts: continuous zoom objective lens, eyepiece and additional front objective lens, as shown in Figure 1. Among them, the continuous variable magnification objective lens belongs to the range of low magnification objective lenses, and is a key component of the video microscope. The observed object is imaged on the photosensitive surface of CCD (or CMOS) through the optical system, and the image sensor converts the optical signal into an electrical signal (video signal), and the signal displays the image of the object on the screen CRT screen or LCD through the TV system. Figure 2 shows the DT-10 single-tube continuous zoom video microscope developed by Guidian Opto-Mechatronics Institute and Wuzhou Aote Optoelectronics Instrument Co., Ltd. through industry-university cooperation. Under the condition of no front objective lens and 1× eyepiece, the zoom ratio M=1:6.3, 0.7～4.5× continuous zoom. After connecting with the 1/3inch CCD through the C interface, the microscopic image is displayed on the CLD. The optical system also uses LED coaxial light illumination with adjustable light intensity or external illumination of annular LED array.
1.2 Automation and intelligent transformation of video microscope
(1) Presentation of the question. Machine vision is widely used in online automatic inspection of industrial production processes, and the "manual adjustment + video observation" mode of continuous zoom video microscope cannot meet the requirements of online automatic inspection.
(2) Overall design scheme. The essence of the intelligent continuous zoom video microscope is to apply embedded technology in the continuous zoom system, replacing the traditional computer to automatically control the automatic system of the microscope action, while reducing the cost, it can quickly realize automatic zoom, focus and detection functions , its simple and practical technology makes it possible to replace manual zoom and computer zoom video microscopes. From the perspective of demand, it must have two functions of automatic focusing and electronic control zoom.
1) It can be seen from the literature that the idea of the designed auto-focusing scheme is that the microscopic image collected by the optical system is detected by "CCD+PC", and then driven by a stepping motor.
2) The electronic control zoom solution is suitable for replacing the manual rotation on the zoom handwheel to achieve different angles, so as to achieve the purpose of continuous zoom of the optical system.
