Research On Key Technology Of Liquid Crystal Display Numeral Instrument Visual Recognition

Visual Inspection Technology has been gradually applied to industrial fields, especially the technology used in the industrial pipeline, which have greatly improved the level of automation in the manufacturing field. Numeral LCD instrument have been gradually applied to many areas, such as the traffic parameters display of motor vehicles, embedded electronic products with LCD screen, consumer electronics, measuring instruments by its unique advantages. The emergence of liquid crystal display facilitates acquirement of information. Equipment that can automatically extract these information and bring feedback to the implementation of systems, would greatly improve efficiency of the information attainment. For these reasons, the paper tries to research and develop a machine vision system that can automatically recognize the number in LCD. The main achievement can summarized as follows:1,Develop a instructive discuss to the camera and lightingIn the part of image acquisition, choose a suitable camera and lighting is the key to the image recognition. This paper focus on how to calculate those parameters such as resolution and scan rate in the state of movement, also it discus how to eliminate noise brought by glisten after using the coaxial lighting. All these discussions lay the foundation for attaining a clear image.2,Remove large background noise of the LCD image, isolated noise existed in the process of binary image.Based on the research of LCD image recognition at home and abroad, this thesis study on main question is as followed. Removing of Large background noise of the LCD image, isolated noise existed in the process of binary image. Through modifying some parameters, improve filtering function base on homomorphism filter so that eliminating large background noise. As much isolated noise will exist in the binary image after image processing, and interfere the recognition. This thesis develops algorithm to eliminate these noise, and give the result after processing.3,Design a simulation system of LCD recognition, develop new functions to expand the scope of the appiication of the platform based on Matlab.Base on the original software structure, achievement of this thesis can embed to the image processing platform. These algorithms includes homomorphism filter, removing of isolated noise and conglutination noise, holes filled and so on. All these method can process the real image and acquire a clear binary image which is the key point in the preprocessing. To verify the effectiveness of algorithms and system, designing a simulation system base on single chip is needed. This system is made up of LCD module YM12864R and C51 microchip processor, and attaining practical value.