基于FPGA的内窥镜窄带光生成方法研究

Research on narrow band imaging method of endoscope based on FPGA

针对传统基于CPU的窄带光内镜系统结构复杂及存在图像延迟等问题,本研究利用FPGA设计和实现了基于光传播特性的内窥镜窄带光生成方法。首先,基于光传播的物理特性,建立相机成像的数学模型,并得出了白光图像到波长为415 nm和540 nm窄带光图像的传递函数;然后,根据传递函数设计了窄带光变换模块,并完成了图像采集模块、内存映射模块及显示模块的硬件设计,实现了基于FPGA的窄带光成像系统。经实验验证,本系统生成的窄带光图像可以有效增强毛细血管与周围组织的对比度,显著提高内窥镜窄带光成像的实时性。

In view of the complex structure and image delay of the traditional narrow-band optical endoscope system based on CPU,the narrow-band optical endoscope generation method was designed and implemented by FPGA based on light propagation characteristics.Firstly,the mathematical model of camera imaging was established based on the physical characteristics of light propagation,and the transfer function from white light images to narrowband light images with wavelengths of 415 nm and 540 nm was obtained.Then,the narrow-band optical transformation module was designed according to the transfer function,and the hardware design of image acquisition module,memory mapping module and display module was completed,and the narrow-band optical imaging system based on FPGA was realized.The experimental results show that the narrow-band light images generated by this system can effectively enhance the contrast between capillaries and surrounding tissues,and significantly improve the real-time performance of endoscopic imaging system.