【作者】 郭俊来；

【导师】 高祥璐； 赵秋生；

【作者基本信息】 天津医科大学 ， 生物医学工程， 2007， 硕士

【摘要】 目的：本课题的宗旨是设计一种带超声波测距装置的新型检影镜,从而达到精确测量人工近视度数并将其在液晶上显示的目的。避免了因检查者与被检者之间的距离而造成的检影验光的误差。方法：利用超声波换能器发出超声波,超声波遇到被检者角膜发生反射,通过单片机对超声波传播时间进行计时并计算出人工近视度数,将其显示在液晶屏上。结果：通过单片机控制超声换能器发出40KHz的超声波,经过反射后可以被接受超声波的换能器接收,频率仍为40KHz。接收到的超声波经过放大整形后产生的低脉冲可以引起单片机的中断,从而可以对超声波传播时间进行计时,根据相关公式计算出了所要测的人工近视屈光度,可以将其显示在液晶屏上,使用者可以直接观察到人工近视的度数。结论：使用本文所设计的新型超声检影镜,直接将其显示的人工近视屈光度结果与反转点时的中和镜片的屈光度进行代数和,就可得到患者的被检查眼实际的屈光度。更多还原

【Abstract】 Objective:The purpose of the project is to design a new retinoscope with the ultrasonic distance measure instrument which can accurately measure the dioptre result of artificial myopia. The result can be displayed on LCD. It can avoid error of measure dioptre caused by measuring distance between optometrist and patient.Method:Energy conversion device of ultrasonic wave transmit ultrasonic wave which occur reflection when meeting cornea of patient. Mono-plate processor reckon time of ultrasonic wave transmitting. The dioptre of artificial myopia is displayed on LCD.Results:Ultrasonic energy conversion device transmit ultrasonic wave of 40 hertz, which is accepted by receptor of ultrasonic energy conversion device after reflecting. Its frequency still is 40 hertz. Break of Mono-plate processor is caused by low voltage impulses which are created by the receptive ultrasonic which being magnified and shaped. Time of ultrasonic wave transmitting is counted. The dioptre of artificial myopia is calculated by related formula. The result is displayed on LCD. User can directly read the dioptre result of artificial myopia.Conclution:Applying the new retinoscope with the ultrasonic distance measure instrument, optometrist can obtain practical dioptre result of patient if only adding the direct dioptre result of artificial myopia to neutral dioptre obtained at roll-back point.更多还原