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1.
基于盖革模式(GM)雪崩光电二极管(GM-APD)探测阵列,设计了一种可用于红外3D成像的高性能红外传感读出电路(ROIC).该电路系统主要由主动淬火电路(AQC)、时间数字转换电路(TDC)和其他时序控制电路3个模块组成.AQC与TDC共同构成像素电路,在其余模块的配合下,由AQC电路检测GM-APD传感器产生的电流信号,TDC电路进行光子飞行时间(TOF)的计量,并转换为数字信号输出,从而实现更好的噪声抑制,更高的探测灵敏度.该电路采用CSMC 0.5μm标准CMOS工艺流片,阵列规模为8×8,像元中心距离100μm,芯片测试结果表明,电路功能良好,在250 MHz时钟驱动下,芯片可达到1 ns的时间分辨率,该电路可用于面阵结构红外探测系统或焦平面阵列.  相似文献   

2.
分析了光电检测时硅光电二极管线性响应及噪声特性,给出了硅光电二极管的线性度及信噪比公式,并结合噪声En-In模型[1],对光电二极管用于光电检测时影响电路信噪比的因素进行了探讨.  相似文献   

3.
自动水龙头的工作原理   总被引:1,自引:0,他引:1  
韩忠全 《物理教师》2005,26(10):9-39
在一些宾馆、饭店、医院等场所,安装着一种红外自动水龙头,当用水人接近水龙头时,龙头便开阔放水,人或物体离开水龙头后,水龙头便关阀停水,这种红外自动水龙头是将红外线发光二极管与光电二极管装置在一起,成为光电耦合器,经光电转换后控制阀门开放和关闭,从而进行自动控制。  相似文献   

4.
生理液滴红外光电自动计数装置的设计与实现   总被引:2,自引:0,他引:2  
利用计算机技术、新型红外光电液滴传感技术和药理学与生理学实验技术相结合的方法,研制了泌尿系统实验的关键实验设备“医学生理液滴红外光电自动计数检测装置”。该装置与传统的实验装置相比,可靠性高,抗干扰能力强,操作使用简便,能准确、灵敏地检测到尿滴通过而导致的信号瞬间变化,实验结果可更客观、更准确地反映各种理化及药物因素对肾功能的影响。  相似文献   

5.
针对傅里叶变换红外光谱仪的优点,测量红外探测器的光谱响应,设计一套新的光电检测系统.通过对测量所得红外干涉信号进行傅里叶变换,得到评判红外探测器性能重要技术指标的光谱响应度.系统在红外探测器光谱响应的测量上,继承了傅里叶变换红外光谱仪的功能和优点,实现了测量分辨率高、精度高和稳定性好.  相似文献   

6.
避障作为机器人的一项最基本的功能,它需要在行动过程中实时监测周围环境障碍物。能够快速且精确的判断出障碍物的位置,对于机器人及时躲避障碍物非常重要。基于红外反射式传感器,利用发射的红外光在遇到障碍物时反射回来,通过检测反射回来的红外光感知障碍物的存在。同时利用音频锁相集成电路LM567,该芯片在电路中既担任振荡器,同时作选频接收。本设计外围电路简单,成本低廉,工作时不受电压温度的影响,可在多种环境下长期稳定的工作。调制发射和接收锁相解调均采用同一芯片,调制发射的频率即为锁相解调的频率,发射和接收始终保持同频。将锁相集成电路输出的信号送给单片机,单片机检测到障碍物的信号后驱动报警器。  相似文献   

7.
为解决传统可见光成像在步态信息检测与身份识别中存在的诸多问题,提出了利用人体红外辐射成像及身份认证的新方法。首先将人体自身辐射的红外光转换为红外热图像,然后分割人体目标并将目标轮廓归一化,同时将轮廓序列叠加以获取红外信息能量图,再对其进行小波分解;提取红外信息能量图分解后的边界矩参数及骨架特征参数,以此作为特征参量输入支持向量机进行身份识别,正确识别率(PCR)为78%~91%,且识别效果不受人体携带外物(如背包、抱球)的影响,仅受衣着的影响较大。研究表明:基于人体红外辐射的身份识别有利于人体目标检测与精确描述。  相似文献   

8.
根据光电信息科学与工程专业光电综合实验课程教学的需要,研制了基于红外遥控的三基色LED调光调色实验教学系统,该系统使用红外遥控器作为控制器,以PIC单片机作为控制芯片,通过红外一体化接收器对红外发射信号进行接收并将解调好的信号送给单片机,单片机将该信号解码并执行相应程序控制对应的LED阵列电路,并通过PWM模块驱动LED亮灭,通过调整占空比输出控制电路的通断时间,高速闪烁的LED在调控不同的占空比下呈现不同的亮度及颜色。利用该实验教学系统可以帮助学生了解并掌握利用PWM技术实现三基色LED的调光方法。  相似文献   

9.
语音心率检测仪是通过红外光电传感器采集手指动脉波信号,经过放大和整形处理,经可调分频器后送人单片机进行计算,快速地转换为一分钟心率,并将结果予以LCD显示,同时有语音播报心率以及警报功能。  相似文献   

10.
本次竞赛设计的电动车跷跷板采用STC12C2052AD单片机作为控制核心,控制电机驱动芯片L293D驱动电动小车进行前进、倒退、转向,利用红外接收、发射二极管做成的传感器,使小车按照指示路线行走,并通过重锤检测控制电动车的运动来保持跷跷板的平衡。  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

13.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

14.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

15.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

16.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

17.
18.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

19.
《海外英语》2007,(4):8-9
城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!  相似文献   

20.
During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.  相似文献   

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