【作者】 宋信强；

【导师】 常大定；

【作者基本信息】 华中科技大学 ， 光学工程， 2007， 硕士

【摘要】 人造视网膜是利用电信号直接刺激视网膜内部神经细胞,从而使外部视网膜病变引起的失明得到恢复。人造视网膜的研究在国内外正掀起一个高潮,用以恢复盲人视觉的人造视网膜是人民健康、国家经济和社会发展的需要。世界卫生组织估计全世界有盲人4000万到4500万,其中有很大部分是由视网膜病变引起的。目前,各个国家都注重恢复盲人视觉的人造视网膜研究,用人造视网膜替代外层受损视网膜(年龄相关性黄斑病变和视网膜色素变性疾病引起)的功能,直接把人造视网膜处理之后的信号刺激视网膜内部神经细胞,从而使盲人恢复视觉。人造视网膜用微电极阵列直接刺激内部神经细胞,而微电极之前的信号处理需要一个数学模型为基础。虽然目前已经有人造视网膜芯片研制成功,已经移植到人眼内部进行实验,取得了一定的效果,但是离实用化、经济性还有一定的距离;并且在基础理论方面各个国家都没有透露自己的关键技术,没有一个统一的模型。本文的研究工作围绕人造视网膜信息提取的数学模型,进行理论分析,为人造视网膜的基础研究提供一种尝试性方法。本文提出一种基于子波变换的灵活可调的人类视觉信息提取模型,用于人造视网膜模型研究。利用子波变换对图像信息处理的灵活方便性,以及子波变换与人类视觉信息提取的相一致性,在目前子波研究的基础上,把子波变换的思想应用于可恢复盲人视觉的人造视网膜信息提取模型之中。模拟结果验证了子波变换用于人造视网膜信息提取模型的合理性,为可恢复盲人视觉的人造视网膜研究提供了一种理论上的可行性模型。更多还原

【Abstract】 Artificial retina is aimed for the stimulation of remained retinal neurons in the patient with degenerated photoreceptors. Many researchers are focus on artificial retina system around the world, as artificial retina is needed for people’s health, developing economy of the country and advancement of the society to cure the blind. The world health organization estimated there are 40 million to 45 million blind around the world. At present, many countries invested much fund in artificial retina research, to substitute the artificial retina for the pathological retina to cure the blind (AMD and RP), by stimulating the inner retinal cells directly with the electrical signals which be produced by artificial retina.Microelectrode arrays have been developed for this as a part of stimulator. Design such microelectrode arrays first requires a suitable mathematical model for human retinal information processing. Also the artificial retina chip had been implanted in the retina to cure the blind in some laboratories, the theoretical model was not uniform and the chip is not economical and practical. This paper is focus on the mathematical model for artificial retina, do theory analyzing, and try to present a theoretical model.In this paper, a flexible and adjustable human visual information abstracting model is presented, which is based on the wavelet transform. With the flexible of wavelet transform to image information processing and the consistent to human visual information extracting, wavelet transform theory is applied to the artificial retina model for the retinally blind.The experiment demonstrates that the visual information extracting model behaves in a manner qualitatively similar to biological retinas and thus may serve as a basis for the development of an artificial retina.更多还原