基于APD的弱光信号探测系统设计及相关特性研究

浙 江 理 工 大 学 机械与自动控制学院

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年 月 日

摘 要

随着光电检测技术的发展及现代化进程的不断推进,光电检测技术的应用领域将越来越广.将广泛应用于工业、农业、家庭 医学、军事和空间科学技术等许多科学领域,并为现代天文学，航空航天，分子生物学、现代医学、环境和生态等新科技的建立和发展提供基础, 而且为现代大工业、现代农业、现代文化事业的大发展也做出不可低估的贡献。本文是对基于APD的微弱光信号探测系统的设计与研究，采用APD作为光电探测器。光电接收器采集数据，经过信号处理电路，模数转换电路传给单片机，单片机通过串口与PC通信，具有测量速度快、体积小、重量轻的优点，适合在线和户外工作。

本设计内容主要有：分析APD的相关特性并设计光学系统；设计直流偏压电路、半导体制冷系统和输出信号处理电路；设计A/D转换电路；设计下位机与上位机串行通行接口电路及部分程序，整个系统具有较高的响应速度和较强的抗干扰性等。

关键词：雪崩二极管；放大电路；半导体制冷器；A/D转换；串口通信

Abstract

With the continuous advance of the photoelectric detection technology development and modernization process, the areas of application of the photoelectric detection technology will be more widely. It will be widely used in many fields such as agriculture, family medicine, military and space science technology, and modern astronomy, besides it provides the basis for the establishment and development of new technology in aerospace, molecular biology, modern medicine, the environment and ecology, and it makes a great contribution for the development of modern industry, modern agriculture, modern culture that can not be underestimated. This article is based on APD the weak optical signal detection system design and research ,as the photoelectric detector, using Avalanche Photo Diode, the photo electronic receivers collect data, amplified circuit, chip microcontroller, pass through serial communication with the PC, not only improve measuring speed, small volume and light weight, suitable for online and field work.

The design elements are: analysis characteristic parameters of APD and optical system design; design APD bias voltage circuit and semiconductor cooling system and output signal processing circuit; design of A /D converter; design with lower computer PC serial communication interface circuit and part of the program; the entire system has a high response speed and strong anti-interference, etc.

Keywords: Avalanche Photo Diode; Amplifier Circuit; semiconductor cooling; analog-digital conversion; serial communication

目 录

摘 要

Abstract

第1章 绪论 ................................................................................................................................. 1

1.1 光电探测器的发展概述 ................................................................................................... 1

1.1.1 光电探测器的发展历史 ....................................................................................... 1

1.1.2 光电探测器的国内外研究现状 ........................................................................... 1

1.2本课题研究的主要内容 .................................................................................................... 4

第2章 总体方案 ........................................................................................................................ 5

2.1 总体设计思路 ................................................................................................................... 5

2.2 功能模块简介 ................................................................................................................... 6

第3章 光电探测器及相关特性 ............................................................................................. 8

3.1 光电探测器 ....................................................................................................................... 8

3.2 几种常用的弱光信号探测器 ........................................................................................... 8

3.3 APD探测器 ...................................................................................................................... 10

3.4 APD相关特性 .................................................................................................................. 11

3.4.1 量子效应与响应度 ............................................................................................. 11

3.4.2 暗电流 ................................................................................................................. 12

3.4.3 倍增因子M .......................................................................................................... 12

3.4.4 过剩噪声 ............................................................................................................. 13

3.4.5 信噪比 ................................................................................................................. 13

第4章 硬件设计 ...................................................................................................................... 15

4.1 APD直流偏压源 .............................................................................................................. 15

4.2 APD恒温控制系统 .......................................................................................................... 16

4.2.1 半导体制冷原理 ................................................................................................. 17

4.2.2 水冷型半导体制冷腔 ......................................................................................... 17

4.2.3 基于单片机的温控系统 ................ …… 此处隐藏：12727字，全部文档内容请下载后查看。喜欢就下载吧 ……