直射光 meaning in English

direct light
directional light

On straight light and reflect light of linear light source
关于线光源的直射光与反射光的研究
In the last two parts we leanred there are skylight from openings , sunlight and indirect light
在前两部分中我们学习了从窗口进入的天光，阳光以及直射光。
Of an interior lighting installation . the ratio of the direct flux on the working plane to the downward flux of the installation
在室内照明系统中，工作面上的直射光通与系统所有向下辐射的光通之比。
The one - half wavelength out of phase caused by the specimen itself enables this light to cause destructive interference with the direct light when both arrive at the intermediate image plane at the diaphragm of the eyepiece
这种由标本产生的半个波长的相位差的光线与直射光同时到达位于目镜光栏的中间像面时会产生相消的干涉。
Such deviated light ( as you will subsequently learn , called diffracted light ) is rendered one - half wavelength or 180 degrees out of step ( more commonly , out of phase ) with the direct light that has passed through undeviated
这种偏移光（其后我们称之为衍射光）与直射光之间呈现半个波长或180的不同步（一般称之为不同相位）。