Most empirically supported mathematical models of rod cells lack theoretical support from actual physical devices. Therefore, this paper proposes an equivalent circuit model for the rod is proposed based on the photoconductive properties of the avalanche photodetector (APD) and combined with the electrical properties of the rod. The model employs the photodetector to simulate the source of the photocurrent in outer segments of rod cells and takes into account the electrical properties of the inner and outer segments, the nucleus, and the synaptic terminals. It successfully simulates the trans-retinal voltage generated by the intracellular and extracellular flow of photocurrent in the outer segment of dark-adapted rods. Moreover, the typical waveform characteristics of two retinal diseases, the enhanced short wavelength sensitivity (SWS) cone syndrome and retinitis pigmentosa (RP), are investigated on the basis of electroretinogram (ERG) a-wave. This will further elucidate the function of the visual system and the ERG a-wave characteristics of the related diseases. Comparison with published experimental results validates the reliability of the model presented. Our study provides new ideas and strategies for the diagnosis of retinal diseases and provides some theoretical support for the application of photodetectors in the fabrication of artificial retinal devices.

中文翻译：

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基于APD的杆等效电路模型研究ERG a波和视网膜疾病

大多数凭经验支持的杆细胞数学模型缺乏实际物理设备的理论支持。因此，本文根据雪崩光电探测器（APD）的光电导特性并结合棒的电特性提出了棒的等效电路模型。该模型采用光电探测器模拟杆状细胞外节的光电流源，并考虑了内节和外节、细胞核和突触末端的电特性。它成功地模拟了暗适应视杆细胞外段细胞内和细胞外光电流流动产生的跨视网膜电压。此外，基于视网膜电图（ERG）a波，研究了两种视网膜疾病的典型波形特征，即短波长敏感性增强（SWS）锥体综合征和色素性视网膜炎（RP）。这将进一步阐明视觉系统的功能以及相关疾病的ERG a波特征。与已发表的实验结果的比较验证了所提出模型的可靠性。我们的研究为视网膜疾病的诊断提供了新的思路和策略，并为光电探测器在人工视网膜装置的制造中的应用提供了一定的理论支持。