论文部分内容阅读
当平行光线射入液体与空气的交界面时,将产生很强的折射和反射作用,因而具有很强的遮光性能。如果在输液瓶两侧对称位置上分别放置光源灯泡L及光电管D,使L光线直射光电管D,当液面A处于光线P所在平面以上时(图1a),光线由光源L经玻璃、液体、玻璃射入光电管D,此时光电管获得电流I_(D1),I_(D1)的大小由瓶内液体的颜色深浅决定,它介于光电管的亮电流和暗电流之间。当液面A下降到正好与光线P所在平面重合时(图1b),光线为液
When parallel light enters the liquid-air interface, it will produce a strong refraction and reflection, which has a strong light-shielding properties. If the light bulb L and the photoelectric tube D are placed symmetrically on both sides of the infusion bottle, the L light is directed to the photoelectric tube D. When the liquid surface A is above the plane where the light P is located (FIG. 1a), the light is emitted from the light source L through the glass, Liquid and glass are injected into the phototube D. At this time, the phototube obtains the current I_ (D1). The magnitude of the I_ (D1) is determined by the color of the liquid in the bottle, which is between the bright and dark current of the phototube. When the liquid level A falls just coincides with the plane of the light P (Fig. 1b), the light is liquid