Just as a double convex lens enlarges , so a double concave lens reduces 正象雙凸透鏡可以放大那樣,雙凹透鏡也可以縮小。
This setup , known as a conoscope , is shown in figure 14 . 2 and consists of two stress - free plano - convex lenses a and b 此裝置稱為錐光鏡,如圖14 2所示,它由a和b兩個無應(yīng)力平凸透鏡組成。
However , spectacles are made of thick convex lens . skills and precautions are needed to wear contact lens properly . both are not suitable for the elderly 不過,這些眼鏡片有相當?shù)暮穸?,配戴隱形眼鏡亦需要一些特別技巧,對于年紀較大的患者未必適合。
This setup , known as a conoscope , is shown in figure 14 . 2 and consists of two stress - free plane - convex lenses a and b and a diaphragm c having a small aperture 此裝置稱為錐光鏡,如圖14 2所示,它由a和b兩個無應(yīng)力平凸透鏡和一個帶小孔的光闌c組成。
However , spectacles are made of thick convex lens . skills and precautions are needed to wear contact lens properly . both are not suitable for the elderly 不過,這些眼鏡片有相當?shù)暮穸?,配戴隱形眼鏡亦需要一些特別技巧,對于年紀較大的患者未必適合。
Since lenticular clouds look like one or more convex lens , they could sometimes be misinterpreted as flying saucers or unidentified flying objects , and so they are commonly known as " flying saucer clouds " 由于這類莢狀云形狀像一塊或多塊凸透鏡,有時候被誤會為飛碟或不明飛行物體,所以亦俗稱飛碟云。
Analysis showed this might be due to the fact that a black hole passed in front of the star . the gravitation of a black hole can function as a convex lens and focus starlight , resulting in transience increase of apparent brightness of the star 分析顯示,這很可能是因為有一個黑洞在恒星前面經(jīng)過,黑洞的引力會聚了星光,就像凸透鏡把光線聚焦一樣,使恒星的視亮度增加。
英文解釋
lens such that a beam of light passing through it is brought to a point or focus 同義詞:converging lens,