首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
The Television Camera The television camera is rather like the human eye. Both the eye and the camera have a lens, and both
The Television Camera The television camera is rather like the human eye. Both the eye and the camera have a lens, and both
admin
2011-01-05
84
问题
The Television Camera
The television camera is rather like the human eye. Both the eye and the camera have a lens, and both produce a picture on a screen. In each case the picture is made up of millions of spots of light.
Let us see how the eye works. When we look at an object-a person, a house, or whatever it may be, we do not see all the details of the object in one piece. We imagine that we do, but this is not the case. In fact, the eye builds up the picture for us in our brain, which controls our sight, in millions of separate parts, and although we do not realize it, all these details are seen separately. This is what happens when we look at something. Beams of light of different degrees of intensity, re-fleeted from all parts of the object, strike the lens of the eye. The lens then gathers together the spots of light from these beams and focuses them on to a light-sensitive plate-the retina-at the back of the eyeball. In this way, an image of the object is produced on the retina in the form of a pattern of lights. The retina contains millions of minute light-sensitive elements, each of which is separately connected to the brain by a tiny fiber in the optic nerve. These nerve fibers, working independently, pick out minute details from the image on the retina and torn the small spots of light into nerve impulses of different strengths. They then transmit these impulses to the brain. They do this all at the same time. All the details of the image are fed to the brain, and as we have taught our brain to add them together correctly, we see a clear picture of the object as a whole.
Television, which means vision at a distance, operates on a similar principle. A television picture is built up in thousands of separate parts. Beams of light reflect from the subject being televised strike the lens of the television camera, which corresponds to the lens of the eye. The camera lens gathers together the spots of light from these beams and focuses an image of the subject on to a plate, the surface of which is coated with millions of photo-electric elements sensitive to light. The spots of light forming the image on the plate cannot be transmitted as light. So they are temporarily converted by an electronic device into millions of electrical impulses ; that is, into charges of electricity. These electrical impulses are then sent through space on a wireless wave to the homes of the viewers. They are picked up by the aerials and conveyed to the receivers to the television set. There, they are finally converted back into the spots of light that make up the picture on the television screen.
All the raps of light reflected from objects are______.
选项
A、of the same intensity
B、of varying intensity
C、to some degree intense
D、not at all intense
答案
B
解析
文中第二段提到“Beams of light of different degrees of intensity,reflected from all parts of the object,strike the lens of the eye.”从物体各部分反射出的不同亮度的光束射到眼睛的晶状体上。different.即不同的,同varying(变化的)相似,其他答案不符合意思。
转载请注明原文地址:https://kaotiyun.com/show/RIQd777K
本试题收录于:
职称英语理工类C级题库职称英语分类
0
职称英语理工类C级
职称英语
相关试题推荐
PromisingResultsfromCancerStudyAnewexperimentalvaccine(疫苗)hasshownpromisingresultsinthefightagainstlungcanc
A.beforethecancercellsspreadelsewhereB.themorechancesofdyingofX-rayradiationhewillhaveC.whatismostrespons
EbolaOutbreak1YouarelikelyawarethatseveralcountriesinWestAfricaarebattlinganEbolaoutbreak.Ebolaisadangerous
Wewereattractedbythelureofquickmoney.
KnowingYourRealPersonalityfromSleepingPositionsEveryonehasgottwopersonalities—theonethatisshowntotheworld
EngineeringEthicsEngineeringethicsisattractingincreasinginterestinengineeringuniversitiesthroughoutthenation,a
HeatandHealthExtremelyhotweatheriscommoninmanypartsoftheworld.Althoughhotweatherjustmakesmostpeoplehot,
Hewasrathervagueaboutthereasonswhyheneverfinishedschool.
HowDidSheConquertheAmericans?African-AmericantalkshowqueenOprahWinfreyistheworld’smostpowerfulcelebrity,acc
Someofthelargerbirdscanremainstationaryintheairforseveralminutes.
随机试题
《中小学教育质量综合评价指标框架(试行)》中的“品德发展水平"的关键指标包括()。
某工程项目招标投标出现的下列情形中,应当视为投标人互相串通投标的有()。
下列房产中。按税法规定可以免征或不征土地增值税的有()。
企业无法可靠区分研究阶段和开发阶段支出的,应将其所发生的研发支出全部资本化计入无形资产成本。()
关于平行结转分步法,下列表述中正确的有()。
不同格式的图像文件其数据编码方式有所不同,通常对应于不同的应用。在下列图像文件格式中,制作网页时用得最多的是()。
计算机网络中,物理地址是指(37),在IP地址和物理地址之间建立映射是因为(38),实现IP地址与物理地址之间映射的协议是(39)。
VFP6.0是一种支持用户使用菜单、命令、______三种不同操作方式的新型数据管理系统。
A、Hewillprovideinvestmentservice.B、Hewillhelpthecustomers.C、Hewilljointhecommercialbank.D、Hewillpurchaseorse
A、Librarianandstudent.B、Fellowprofessors.C、Fellowstudents.D、Professorandstudent.C
最新回复
(
0
)