【作者】 李浩；

【导师】 陈良洲；

【作者基本信息】 华中科技大学 ， 机械工程， 2024， 硕士

【摘要】 眼内压是治疗青光眼疾病的关键生理指标。对眼内压进行连续且准确的测量能够获取更多有效的眼部信息,是临床治疗青光眼疾病的关键所在。LC(电感电容谐振)眼压传感器是当前主流的非侵入式长程眼压测量手段之一,但缺少合适的传感器信号采集设备。为了实现对眼内压连续且准确的测量,针对LC眼压传感器设计了一种低成本、便携式的传感器信号无线采集系统。明确了系统整体的关键技术指标,并对传感器机理进行了分析,比较现有的信号检测方案,以提高信号采集系统的测量精度和集成度为设计目标,选用了基于幅值相位检测的传感器谐振频率信号测量方案,针对此方案进行系统的硬件电路设计和软件设计。硬件电路是以微控制器为核心的嵌入式设备,根据所要实现的功能将电路按模块分为了扫频信号输出电路、幅值相位检测电路、嵌入式主控电路、读取线圈电路、电源和蓝牙通信电路。明确了电路中各个模块的设计要求,并进行信号调试和样机制作。软件层面完成了程序的控制逻辑,实现了洛伦兹函数拟合的数据处理算法,进一步提高了测量精度。同时开发了一款上位机可视化软件,实现数据的可视化、预处理和存储功能。实验阶段主要在人工硅胶眼球上对LC眼压传感器进行信号测量。测试得到,该信号采集系统在10～50 mmHg的压力范围内能够实现±1.5 mmHg的测量精度,灵敏度可达62.3 kHz/mmHg,满足实际测量需求。更多还原

【Abstract】 Intraocular pressure(IOP)is a key physiological indicator for the treatment of glaucoma.Continuous and accurate measurement of IOP can obtain more effective ocular information,which is the key to the clinical treatment of glaucoma.LC(InductanceCapacitance resonance)IOP sensor is one of the mainstream non-invasive methods of measuring IOP in long-term,but there is a lack of suitable sensor signal acquisition equipment.In order to achieve continuous and accurate measurement of IOP,a low-cost,portable sensor signal wireless acquisition system is designed for LC IOP sensors.The key technical indexes of the whole system are defined,and the mechanism of the sensor is analyzed.Compared with the existing signal detection schemes,in order to improve the measurement accuracy and integration of the signal acquisition system,the sensor resonance frequency signal measurement scheme based on amplitude phase detection is selected.The hardware circuit design and software design of the system are carried out.The hardware circuit is an embedded device with a microcontroller as the core.According to the functions to be realized,the circuit is divided into a sweep signal output circuit,an amplitude and phase detection circuit,an embedded main control circuit,a reading coil circuit,a power supply and a Bluetooth communication circuit.The design requirements of each module in the circuit are clarified,and the signal debugging and prototype production are carried out.At the software level,the control logic of the program is completed,and the data processing algorithm of Lorentz function fitting is realized,which further improves the measurement accuracy.At the same time,a host computer visualization software was developed to realize data visualization,preprocessing and storage functions.In the experimental stage,the IOP sensor is mainly measured on the artificial silicone eyeball.The test results show that the signal acquisition system can achieve the measurement accuracy of ± 1.5 mmHg in the pressure range of 10～50 mmHg,and the sensitivity can reach 62.3 kHz/mmHg,which meets the actual measurement requirements.更多还原