亮(liang)度增(zeng)(zeng)益決定(ding)了一(yi)塊銀(yin)幕終呈現影像的亮(liang)度， 一(yi)般在1.0?3.0之間。但是，它(ta)又與(yu)散射角密切相 關。可(ke)以理解(jie)的是，它(ta)是把(ba)幕面反(fan)射的光線聚攏來 才(cai)能實(shi)現亮(liang)度增(zeng)(zeng)益大(da)于(yu)1的結果(guo)。也就是控制散射 角，使得(de)反(fan)射更集中于(yu)觀眾(zhong)區(qu)，因而看(kan)上去(qu)更亮(liang)了。

可見散(san)射角越(yue)小，亮(liang)(liang)度(du)(du)增益越(yue)高。但是(shi)，散(san)射角越(yue) 小，我(wo)們(men)視線(xian)垂直正對(dui)銀幕的(de)區域越(yue)亮(liang)(liang)，離開視線(xian) 垂直正對(dui)銀幕的(de)區域就暗(an)了，這就是(shi)高亮(liang)(liang)度(du)(du)增益銀幕所(suo)帶來(lai)的(de)太陽斑效(xiao)應(ying)。這種現象(xiang)越(yue)嚴(yan)重，我(wo)們(men)看上去影像亮(liang)(liang)度(du)(du)的(de)均勻度(du)(du)越(yue)差(cha)，正所(suo)謂中間亮(liang)(liang)四周暗(an)。

因此，亮度(du)(du)增益數值(zhi)并(bing)不是越高越好，我們(men)只 能在放映機流明(ming)輸(shu)出與銀幕亮度(du)(du)增益之(zhi)間做平(ping)衡，3D電(dian)影銀幕廠(chang)家，

銀幕是(shi)指能接受幻燈、投(tou)影、電影等(deng)設備所投(tou)射出(chu)的(de)(de)光束(shu)，并(bing)在其(qi)表面顯示圖像的(de)(de)白色特z制平(ping)面，也稱之為(wei)放(fang)映(ying)銀幕。它(ta)對放(fang)映(ying)畫面的(de)(de)亮度(du)、清晰度(du)、對比度(du)、色彩還(huan)原和放(fang)映(ying)聲(sheng)音起著重要的(de)(de)作用。

目(mu)前常用(yong)的銀幕(mu)(mu)按幕(mu)(mu)面的光學特(te)性分為(wei)兩大類：反射(she)式銀幕(mu)(mu)和透射(she)式銀幕(mu)(mu)。

反(fan)射(she)式(shi)銀(yin)幕(mu)(mu)(mu)(mu)(mu)不受(shou)尺寸限制，但受(shou)環境(jing)光線(xian)的影響(xiang)較(jiao)大，包括各(ge)種規格的手動(dong)掛(gua)幕(mu)(mu)(mu)(mu)(mu)和電動(dong)掛(gua)幕(mu)(mu)(mu)(mu)(mu)。如升降幕(mu)(mu)(mu)(mu)(mu)、支架幕(mu)(mu)(mu)(mu)(mu)、地(di)拉(la)幕(mu)(mu)(mu)(mu)(mu)、桌幕(mu)(mu)(mu)(mu)(mu)、金(jin)屬平面(mian)幕(mu)(mu)(mu)(mu)(mu)、弧(hu)面(mian)幕(mu)(mu)(mu)(mu)(mu)等(deng)。反(fan)射(she)式(shi)銀(yin)幕(mu)(mu)(mu)(mu)(mu)按照光學原理(li)分(fen)為(wei)(wei)漫散反(fan)射(she)銀(yin)幕(mu)(mu)(mu)(mu)(mu)和方(fang)向性漫散反(fan)射(she)銀(yin)幕(mu)(mu)(mu)(mu)(mu)。透射(she)型(xing)銀(yin)幕(mu)(mu)(mu)(mu)(mu)畫(hua)面(mian)整體感(gan)較(jiao)強，不受(shou)環境(jing)光線(xian)的影響(xiang)，銀(yin)幕(mu)(mu)(mu)(mu)(mu)，能正確(que)反(fan)映圖(tu)像質(zhi)(zhi)量，畫(hua)面(mian)色彩(cai)艷麗(li)，影院銀(yin)幕(mu)(mu)(mu)(mu)(mu)價格，形象逼真，包括各(ge)種規格的硬質(zhi)(zhi)透射(she)幕(mu)(mu)(mu)(mu)(mu)和軟(ruan)質(zhi)(zhi)背投(tou)幕(mu)(mu)(mu)(mu)(mu)。透射(she)式(shi)銀(yin)幕(mu)(mu)(mu)(mu)(mu)按照光學原理(li)多為(wei)(wei)方(fang)向性漫散透射(she)銀(yin)幕(mu)(mu)(mu)(mu)(mu)。

關于穿孔銀幕簡介

通常放映時(shi)為(wei)了使(shi)(shi)聲音與畫面(mian)(mian)效(xiao)果(guo)配(pei)合協調一致揚聲器(qi)蕞好(hao)放置在銀(yin)幕(mu)后的(de)(de)正中(zhong)央處，這(zhe)(zhe)時(shi)就會影響(xiang)聲音的(de)(de)高(gao)頻特性。為(wei)了提高(gao)聲音保真度，可使(shi)(shi)用穿孔(kong)(kong)(kong)(kong)(kong)銀(yin)幕(mu)。銀(yin)幕(mu)穿孔(kong)(kong)(kong)(kong)(kong)既要獲取(qu)蕞佳的(de)(de)聲學(xue)特性，又(you)要使(shi)(shi)觀(guan)(guan)眾觀(guan)(guan)察不(bu)到幕(mu)孔(kong)(kong)(kong)(kong)(kong)。穿孔(kong)(kong)(kong)(kong)(kong)銀(yin)幕(mu)的(de)(de)構造(zao)是(shi)在幕(mu)面(mian)(mian)均(jun)勻(yun)打(da)上很(hen)多(duo)小孔(kong)(kong)(kong)(kong)(kong)，一般孔(kong)(kong)(kong)(kong)(kong)的(de)(de)直徑在0.5－1.2mm之間，流動電(dian)影銀(yin)幕(mu)，小孔(kong)(kong)(kong)(kong)(kong)之間應有5.5mm的(de)(de)間隔(ge)：小孔(kong)(kong)(kong)(kong)(kong)面(mian)(mian)積總和占(zhan)銀(yin)幕(mu)面(mian)(mian)積的(de)(de)2％～5％左右，這(zhe)(zhe)樣觀(guan)(guan)眾在觀(guan)(guan)看(kan)影像時(shi)看(kan)不(bu)到小孔(kong)(kong)(kong)(kong)(kong)。穿孔(kong)(kong)(kong)(kong)(kong)銀(yin)幕(mu)有不(bu)同的(de)(de)幕(mu)面(mian)(mian)構造(zao)。常見的(de)(de)有橡皮穿孔(kong)(kong)(kong)(kong)(kong)幕(mu)、塑料穿孔(kong)(kong)(kong)(kong)(kong)幕(mu)、玻(bo)璃珠穿孔(kong)(kong)(kong)(kong)(kong)幕(mu)、金屬穿孔(kong)(kong)(kong)(kong)(kong)幕(mu)等(deng)。銀(yin)幕(mu)經穿孔(kong)(kong)(kong)(kong)(kong)后，其表面(mian)(mian)特性不(bu)變，只是(shi)改變了音響(xiang)效(xiao)果(guo)。穿孔(kong)(kong)(kong)(kong)(kong)銀(yin)幕(mu)因幕(mu)面(mian)(mian)有孔(kong)(kong)(kong)(kong)(kong)，透(tou)光較多(duo)，亮(liang)度將降(jiang)低。