Deflections of the suspended needle are indicated by the movement of a narrow beam of light which the mirror reflects from a lamp and focusses upon a graduated cardboard scale placed at a distance of a few feet; the angular deflection of the beam of light is, of course, twice that of the needle.
From the above instances we see that an instrumental appliance that polarizes a beam of light may be used as a means of detecting and examining polarization.
We may now investigate the mathematical expression for the disturbance propagated in any direction from a small particle upon which a beam of light strikes.
Later investigations by Fraunhofer, Airy and others have greatly widened the field, and under the head of diffraction are now usually treated all the effects dependent upon the limitation of a beam of light, as well as those which arise from irregularities of any kind at surfaces through which i
beam of light הגייה עם משמעויות, מילים נרדפות, הפכים, תרגומים, משפטים ועוד