完全聚焦作用与测试屏幕上亮区的形成机理  

Shaping mechanism of bright area on the test screen and the sharp focusing effect

作　　者：陈务深[1] 朱耀亮[1] 戴沨[1] 

机构地区：[1]南京工业大学理学院,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2003年第6期87-89,共3页Journal of Nanjing Tech University(Natural Science Edition)

摘　　要：;证明了与测试屏幕上B点和C点相对应的灯丝上的起亮点为完全聚焦点,指出了在仅考虑完全聚焦效应的前提下,不在焦点的灯丝上的点光源所发出的光线,经过旋转抛物面的反射,于测试屏幕上相应地形成由两条曲线所组成的桃形入射轨线。分析结果还表明,以组成桃形入射轨线的两条曲线为中心,在测试屏幕上分别形成两条距离很近的亮带。利用此结论,可以知道,随着灯丝的变长,亮带不断外推,从而在测试屏幕上形成连续的亮区,这比较清楚地解释了测试屏幕上桃形亮区的形成机理。It is proved that the starting points on linear headlight source, which are related to B or C on the test screen, are sharp focusing. By considering the sharp focusing effect, it can be found that some light emitted from a point on the filament, which is not on the focus, can form two closely placed peach-form bight curves on the screen. Correspondingly, there exist two bright zones centered around those ones on the testing screen. Therefore, along with the increasing of the filament length, the corresponding bight zone becomes larger and larger, and a continuously peach-form bright area can be formed on the test screen.

关 键 词：完全聚焦作用 测试 屏幕 亮区 形成机理 入射轨线 反射定律 

分 类 号：O435.1[机械工程—光学工程] O432.2[理学—光学]