一(yi).明視(shi)野觀察明視(shi)野鏡(jing)(jing)檢(jian)是大家(jia)比較熟悉的一(yi)種鏡(jing)(jing)檢(jian)方式,廣泛應用(yong)于(yu)病理、檢(jian)驗,用(yong)于(yu)觀察被染色(se)的切片(pian),所有光學顯微(wei)鏡(jing)(jing)均(jun)能完成此功能。
二.暗(an)視(shi)野觀(guan)(guan)察(cha)(cha)暗(an)視(shi)野實際是(shi)(shi)暗(an)場(chang)照明發。它的(de)(de)(de)(de)(de)特(te)(te)點(dian)和明視(shi)野不同,不直接觀(guan)(guan)察(cha)(cha)到照明的(de)(de)(de)(de)(de)光(guang)(guang)(guang)(guang)(guang)線(xian),而(er)觀(guan)(guan)察(cha)(cha)到的(de)(de)(de)(de)(de)是(shi)(shi)被(bei)(bei)檢物(wu)(wu)體(ti)反(fan)射或衍射的(de)(de)(de)(de)(de)光(guang)(guang)(guang)(guang)(guang)線(xian)。因此,視(shi)場(chang)成為(wei)黑暗(an)的(de)(de)(de)(de)(de)背景,而(er)被(bei)(bei)檢物(wu)(wu)體(ti)則呈現明亮(liang)的(de)(de)(de)(de)(de)象(xiang)。暗(an)視(shi)野的(de)(de)(de)(de)(de)原理(li)是(shi)(shi)根據光(guang)(guang)(guang)(guang)(guang)學上的(de)(de)(de)(de)(de)丁道(dao)爾現象(xiang),微塵在(zai)強光(guang)(guang)(guang)(guang)(guang)直射通過的(de)(de)(de)(de)(de)情況下,人眼不能觀(guan)(guan)察(cha)(cha),這是(shi)(shi)因為(wei)強光(guang)(guang)(guang)(guang)(guang)繞(rao)射造成的(de)(de)(de)(de)(de)。若把光(guang)(guang)(guang)(guang)(guang)線(xian)斜(xie)射它,由(you)于光(guang)(guang)(guang)(guang)(guang)的(de)(de)(de)(de)(de)反(fan)射,微粒似乎增(zeng)大了體(ti)積,為(wei)人眼可見。m..m暗(an)視(shi)野觀(guan)(guan)察(cha)(cha)所(suo)需要的(de)(de)(de)(de)(de)特(te)(te)殊附件(jian)是(shi)(shi)暗(an)視(shi)野聚光(guang)(guang)(guang)(guang)(guang)鏡。它的(de)(de)(de)(de)(de)特(te)(te)點(dian)是(shi)(shi)不讓光(guang)(guang)(guang)(guang)(guang)束由(you)下至上的(de)(de)(de)(de)(de)通過被(bei)(bei)檢物(wu)(wu)體(ti),而(er)是(shi)(shi)將光(guang)(guang)(guang)(guang)(guang)線(xian)改變途(tu)徑,使其斜(xie)射向(xiang)被(bei)(bei)檢物(wu)(wu)體(ti),使照明光(guang)(guang)(guang)(guang)(guang)線(xian)不直接進入物(wu)(wu)鏡,利用被(bei)(bei)檢物(wu)(wu)體(ti)表面反(fan)射或衍射光(guang)(guang)(guang)(guang)(guang)形成的(de)(de)(de)(de)(de)明亮(liang)圖象(xiang)。暗(an)視(shi)野觀(guan)(guan)察(cha)(cha)的(de)(de)(de)(de)(de)分辨率遠高于明視(shi)野觀(guan)(guan)察(cha)(cha),更(geng)高達0.02—0.004
二.暗(an)視(shi)(shi)(shi)野(ye)(ye)觀(guan)(guan)察(cha)暗(an)視(shi)(shi)(shi)野(ye)(ye)實際是暗(an)場照明(ming)(ming)發。它的特點(dian)和明(ming)(ming)視(shi)(shi)(shi)野(ye)(ye)不(bu)同(tong),不(bu)直(zhi)接觀(guan)(guan)察(cha)到照明(ming)(ming)的光(guang)(guang)(guang)線,而(er)觀(guan)(guan)察(cha)到的是被(bei)(bei)檢(jian)物(wu)(wu)體(ti)(ti)反射(she)(she)(she)或(huo)衍(yan)射(she)(she)(she)的光(guang)(guang)(guang)線。因(yin)此,視(shi)(shi)(shi)場成為(wei)黑暗(an)的背景,而(er)被(bei)(bei)檢(jian)物(wu)(wu)體(ti)(ti)則(ze)呈現明(ming)(ming)亮的象。暗(an)視(shi)(shi)(shi)野(ye)(ye)的原(yuan)理(li)是根(gen)據(ju)光(guang)(guang)(guang)學上的丁道爾現象,微塵在強(qiang)光(guang)(guang)(guang)直(zhi)射(she)(she)(she)通(tong)過的情況下(xia),人(ren)眼不(bu)能觀(guan)(guan)察(cha),這是因(yin)為(wei)強(qiang)光(guang)(guang)(guang)繞射(she)(she)(she)造(zao)成的。若把(ba)光(guang)(guang)(guang)線斜(xie)射(she)(she)(she)它,由(you)于(yu)光(guang)(guang)(guang)的反射(she)(she)(she),微粒似乎增大了體(ti)(ti)積(ji),為(wei)人(ren)眼可見(jian)。m..m暗(an)視(shi)(shi)(shi)野(ye)(ye)觀(guan)(guan)察(cha)所需(xu)要的特殊附件是暗(an)視(shi)(shi)(shi)野(ye)(ye)聚光(guang)(guang)(guang)鏡。它的特點(dian)是不(bu)讓(rang)光(guang)(guang)(guang)束(shu)由(you)下(xia)至上的通(tong)過被(bei)(bei)檢(jian)物(wu)(wu)體(ti)(ti),而(er)是將光(guang)(guang)(guang)線改變途徑(jing),使(shi)其(qi)斜(xie)射(she)(she)(she)向被(bei)(bei)檢(jian)物(wu)(wu)體(ti)(ti),使(shi)照明(ming)(ming)光(guang)(guang)(guang)線不(bu)直(zhi)接進入(ru)物(wu)(wu)鏡,利用被(bei)(bei)檢(jian)物(wu)(wu)體(ti)(ti)表面反射(she)(she)(she)或(huo)衍(yan)射(she)(she)(she)光(guang)(guang)(guang)形成的明(ming)(ming)亮圖象。暗(an)視(shi)(shi)(shi)野(ye)(ye)觀(guan)(guan)察(cha)的分辨率遠高(gao)于(yu)明(ming)(ming)視(shi)(shi)(shi)野(ye)(ye)觀(guan)(guan)察(cha),更(geng)高(gao)達0.02—0.004
三.相(xiang)差(cha)鏡(jing)檢法在光學顯(xian)微(wei)鏡(jing)的(de)發展過(guo)程中(zhong)(zhong),相(xiang)差(cha)鏡(jing)檢術(shu)的(de)發明成功,是(shi)近代光學顯(xian)微(wei)鏡(jing)技(ji)術(shu)中(zhong)(zhong)的(de)重要成就。我(wo)們知道(dao),人眼只(zhi)能區分(fen)光波的(de)波長(顏色(se))和振(zhen)幅(fu)(亮度(du)),對于無色(se)通明的(de)生物標本,當光線通過(guo)時,波長和振(zhen)幅(fu)變化不大,在明場觀察時很難觀察到標本.