The practical optician's guide : an elementary course for opticians / by Harry L. Taylor.

  • Taylor, Harry L.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: The practical optician's guide : an elementary course for opticians / by Harry L. Taylor. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    Refraction of Light. 1. Rays of Light. Light travels in straight lines, were it not so we should be able to see round a corner. For the convenience of description we speak of a ray of light meaning a very small line or streak. The grouping of a number of rays together forms a pencil or beam, such as is seen when bright sunlight streams through a small hole in a dark room. 2. Refraction of a Ray. The whole science of Optics is founded on the peculiar bending or deflection which light undergoes in passing from one medium to another of different density. As shown in the following illustration, unless the ray strike the surface between the two media obliquely no refraction takes place. A B is a section of a sheet of glass, and C D a line drawn perpendicular to the surface. A ray of light passing along C D would undergo no refraction.
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