毕业论文（设计）基于STC89C52的光电计数器设计说明书.docVIP

光电计数器的设计 摘 要 本系统采用的是以单片机STC89c52为核心的自动计数器。采用反射式光电传感器，将红外发光管与光电接收管相邻安放，每当物体通过一次，红外光就被物体反射，光电接收管接收一次，光电接收管的输出电压就发生一次变化，这个变化的电压信号通过放大和处理后，形成计数脉冲，通过光电隔离耦合并行输入至STC89c52单片机的P1口，通过软件控制和键盘设定计数值并用LED加以显示，便可实现对物体的计数统计。 所谓的光电传感器是将光信号转化为电信号的一种传感器。它的理论基础是光电效应。这类效应大致可分为三类。第一类是外光电效应，即在光照射下，能使电子逸出物体表面。利用这种效应所做成的器件有真空光电管、光电倍增管等。第二类是内光电效应，即在光线照射下，能使物质的电阻率改变。这类器件包括各类半导体光敏电阻。第三类是光生伏特效应，即在光线作用下，物体内产生电动势的现象，此电动势称为光生电动势。这类器件包括光电池、光电晶体管等。光电效应都是利用光电元件受光照后，电特性发生变化。敏感的光波长是在可见光附近，包括红外波长和紫外波长。市场上的光电计数器采用的光电传感器有摄像头、光电管等，采用的光的种类有普通光和激光，可见光和不可见光等。光电传感器一般由光源、光学通路和光电元件三部分组成。光电式传感器是以光电器件作为转换元件的传感器，光电检测方法具有精度高、应用快、非接触等优点，而可测参数多，光电传感器的结构简单，形式灵活多变,因此，光电传感器在检测和控制中应用非常广泛。 关键词 计数器 光电传感器 单片机 数码管  Abstract The system USES the microcontroller is STC89c52 as the core of the automatic counters. By reflecting photoelectric sensor, the infrared luminescence tubes and optoelectronics receiving tube adjacent put, whenever objects through time, infrared light is reflected, photoelectric receiving tube receiving once, photoelectric receiving pipe output voltage has a time change, this change voltage signal by amplifying and processed, forming counting pulses, through photoelectric isolating coupling parallel input to STC89c52 MCU P1 mouth, through software control and keyboard Settings count value and LED to display, can realize to the object counting statistics. This counter can or mechanical artificially count way into electronic counted, and using LED digital pipe display, can be applied to many professions, to meet modern production and lifestyle needs. The so-called photoelectric sensor is light signals are converted to electrical signals a sensor. It is based on the theory of the photoelectric effect. This kind of effect can be roughly classified into three kinds. The first kind is the photoelectric effect, namely in light, can make the electronic escaping surface. Using this effect made devices have vacuum phototubes, photomultiplier tubes, etc. The second type is inside the photoelectric effect, t