The Image Acquisition System Of Capsule Endoscopy Based On Wireless Energy Transfer

The rate of digestive system diseases grows quickly due to the rapid social development and diet structure changed, the patient endu re intolerable pain with traditional mechanical endoscopy, it also may cause the check trauma and cross inflection, a kind of minimally in vasive/noninvasive diagnosis of digestive tract diseases diagnostic equ ipment: capsule endoscopy system is developed in this paper.This endoscopy system is mainly composed by data capture mo dule, data compression module, data transmission module and extraco rporeal data receiving module. The working process is as follows: af ter the patient swallow capsule, the data capture module and data co mpression module will capture image data of inner wall of the diges tive tract and compress these image data, then the data transmission module will transmit the image data to the extracorporeal data receiv ing module, these data can be restored to JPEG images on the comp uter for human observation, then the doctor can use these images to detect and analyze digestive tract lesions.When the Given Imaging corporation of Israel launches the first clinical capsule at 2000, after 20 years of development, a lot of tech nologies related to capsule applications, such as technology of data a cquisition and compression, wireless transmission technology, technolo gy of minimize power consumption and geometrical size have been greatly developed. But there are still many difficulties in practical ap plication of capsule: the precise control of posture and position of capsule in the digestive tract, the continuous long work time of capsul e, low capture image quality and so on.This design is supported by the National Natural Science Found ation of China(NO. 31271069), Youth Fund of National Natural Sci ence Fund(NO. 30800235) and Shanghai Jiao Tong Univ. Medical-en gineering Cross Fund(NO. YG2013MS24). This project proposes usin g an external permanent magnet for interacting with the capsule insi de the digestive track, then doctors can control the position and gest ure of the capsule to decrease the possibility of miss-detection. This project also propose of wireless energy transfer by using extracopore al alternating magnetic field influencing coil inside the capsule, then th e wireless energy transfer module can afford power to intracorporal wireless capsule, it leads capsule to work sufficient time in digestive track. On the basis of video navigation, this project also puts forwar d the concept of controllable, movable and therapeutic platform for i ntegrating treat tools like: electrical stimulation and heat treatment m odule to inside of capsule.This design focuses on the digital image acquisition subsystem t o obtain high image compression ratio, mainly study the principle of capsule based on JPEG format, then design the system and impleme nt the function. Image acquisition module includes image capture and image compression part. Image capture module uses the digital outp ut of CMOS image sensor OV7740, then compresses the image data through specialized image compression chip CX93510, at last transmi ts the image data to PC through UART, PC client restores the imag e data to JPEG image and authenticate the data.The experiment results shows that the diameter of the capsule is11 mm, it can be used to swallow without uncomfortable feelings. I n the relatively simple work environment of background, the image acquisition module can work efficiently and stably under an approxi mately compression ratio of 40:1, image data can be effectively reduced by this system on the basis of guarantee image quality, decrease s the load pressure of wireless transmission, improves transmission ra te of frame image.