Real-time Acquisition And Processing Of B-scan Ophthalmic Ultrasound Images Based On USB

Traditional B-scan Ophthalmic Ultrasound apparatus has no images storage capability and images can only be displayed on the screen of apparatus. This limits the re-use and image-processing in the following aspects:1. It's difficult to store images because of insufficient space. Therefore, the images are often saved by video-copy.2. It's unable to process images using some complicated methods because of hardware limitation.However, if the images can be required in real-time and transferred to PC to display, using PC's powerful function, the images re-use and processing can be realized easily. This could facilitate the clinical diagnosis and improve its reliability.For this, a new method of real-time image-acquisition from B-scan Ophthalmic Ultrasound apparatus was presented. Firstly, the SVGA digital signal was acquired from the front-end of VGA connector and then was transmitted to SRAM and USB-chip controlled by FPGA. Secondly, the image-data (from SVGA signal) were encoded to reduce errors during transmission. Finally, the image-data were decoded by PC software to display and process.The system development consists of two parts:the hardware (PCB designing, FPGA programming and the development of USB firmware) and the software (the development of USB drive and the PC software). This subject is mainly responsible for the hardware part.This subject, who has technical advantages, explored the feasibility of real-time transmission and display of B-scan ultrasound images with USB. Furthermore, it indicated that digital video acquisition can transmit images with high-fidelity and high-speed, and can make the images easy to store and process. The totally digital-acquisiton method is not only an important part in research of totally digital B-scan Ophthalmic Ultrasound, but also an exploring of infomationization of B-scan Ophthalmic Ultrasound. It has important meanings both in practical application and theory research.