图形显示设备ppt课件

.,1,2.2图形显示设备,2.2.1阴极射线管(CRT)阴极射线管、彩色阴极射线管2.2.2CRT图形显示器随机扫描、直视存储管、光栅扫描2.2.3平板显示器（flat-paneldisplay）*液晶显示器、等离子体显示板、薄片光电显示器、发光二极管显示器、激光显示器2.2.4三维观察设备,.,2,2.2.1阴极射线管(CRT),(一)阴极射线管(二)彩色阴极射线管,.,3,(一)阴极射线管,CRTCathodeRayTubeAnode,.,4,从外形上看：管颈部分、锥体部分、屏幕部分从结构上看：电子枪、偏转系统、荧光屏,Flash演示,.,5,1.电子枪,阴极,栅极,加速阳极,聚焦阳极截止电压:栅极负压使电子束电子流为0时的电压值.,.,6,2.偏转系统,磁偏转电偏转,.,7,.,8,电偏转,灯,丝,阴,极,加,速,极,控,制,栅,聚,焦,极,加,速,极,荧,光,屏,图2-7CRT的构造（电偏转）,水,平,偏,转,板,垂,直,偏,转,板,.,9,3.荧光屏(PhosphorScreen),余辉特性-p28余辉时间,.,10,(二)彩色阴极射线管,三基色原则:红(Red,R)绿(Green,G)蓝(Blue,B)物理三基色色域-红,黄,蓝,.,11,彩色阴极射线管,荫罩式彩色显象管ShadowMask穿透式彩色显示Beam-Penetration,.,12,荫罩式彩色显象管,主要结构：三色荧光屏三支电子枪荫罩板,.,13,三色荧光屏,荫罩板,.,14,三支电子枪,Flash演示,.,15,荧光点的面积比电子束截面大只有15%左右的电子到达屏幕,.,16,改进:黑底荫罩管,.,17,彩色显象管必须满足的要求,色纯会聚白色平衡p31,.,18,2.穿透式彩色显示原理,红,橙,黄,绿,.,19,2.2.2CRT图形显示器,随机扫描的图形显示器直视存储管图形显示器光栅扫描的图形显示器,.,20,1.随机扫描的图形显示器,向量(vector)显示器笔划(Strokewriting)显示器Random-ScanFlash演示,.,21,2.直视存储管图形显示器,直视存储管DVST（direct-viewstoragetube）,.,22,存储管显示器结构示意图,Flash演示,屏,幕,存储栅,收集栅,写电,子抢,电子流,读出电子抢,写阴极,.,23,3.光栅扫描的图形显示器,Raster-ScanDisplays,.,24,Flash演示,.,25,几个概念,刷新速率：60到80帧/秒(60Hz或80Hz)水平回扫(HorizontalRetrace):行扫描垂直回扫(VerticalRetrace):场扫描(帧扫描)逐行扫描和隔行(interlaced)扫描,.,26,.,27,像素pixel或pel,PictureElement的简写Eachscreenspotthatcanbeilluminatedbytheelectronbeamisreferredtoasapixel.,.,28,帧Frame,Framereferstothetotalscreenarea.,.,29,刷新缓冲存储器RefreshBuffer帧缓冲存储器FrameBuffer,.,30,00000000000000000000000000000000000000011111100000000000111111000000000001111110000000000000000000000000000000000000000,帧缓存,显示器,.,31,TheDepthoftheFrameBuffer,Thenumberofbitsthatareusedforeachpixel.,.,32,举例,one-bit-deepframebufferallows2colors8-bit-deepframebufferallows28(=256)colors,.,33,Full-colorsystemTruecolorsystem,24ormorebitsperpixel,.,34,位图Bitmap,Aframebufferwithonebitperpixeliscalledbitmap,.,35,Pixmap,Aframebufferwithmultiplebitsperpixelisapixmap.,.,36,分辨率Resolution,Resolutionisthenumberofpixelpositionsthatcanbeplotted.,.,37,屏幕长宽比AspectRatio,水平点数和垂直点数之比,.,38,扫描转换Scan-Conversion,象素信息从应用程序转换,并放入帧缓冲区的过程,.,39,Rasterscan,.,40,Randomscan,.,41,走样与反走样,.,42,2.2.3平板显示器（flat-paneldisplay）*,液晶显示器等离子体显示板薄片光电显示器发光二极管显示器激光显示器,.,43,2.2.4三维观察设备*,方法一:采用从变焦距的柔性震动镜面反射CRT图象的技术方法二:显示具有立体感的视图,.,44,一.从变焦距的柔性震动镜面反射CRT图象,.,45,二.显示具立体感的视图,DisplaystereoscopicviewoftheobjectProvidingdifferentviewofeacheye.,.,46