Think of glass as a uniform array of tiny capacitors. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why is glass transparent? Ask Question. Asked 10 years, 7 months ago. Active 2 years, 2 months ago. Viewed k times. Improve this question. Add a comment. Active Oldest Votes. There are important differences in these absorption possibilities: Atoms absorb well-defined discrete frequencies.
Usually single atoms absorb only a few frequencies - it depends on the energetic spectrum of its electrons. Regarding atomic absorption, the graph of absorption plotted as a function of frequency of light contains well-defined peaks for frequencies when absorption occurs, and no absorption at all between them. Molecules absorb discrete frequencies but there are many more absorption lines because even a simple molecule has many more energetic levels than any atom.
So molecules absorb much more light. Crystalline lattices may absorb not only discrete frequencies but also continuous bands of frequencies, mainly because of discrepancies in the crystalline structure. Improve this answer. Do other type of photons behave like visible light i. When You try to analyse light and matter interactions there is many process to take into account.
But from the form of the question I presume You need a basic level answer. Real interaction is quantum one in absorption-emission area, but may be wave dynamic in certain frequencies - for example interference should be analysed etc.
It is rather complicated when You would like to take account on all phenomena which may occur. In spite of being non-crystalline, glasses too have bands. Show 2 more comments. Marek Marek That is why glass is not only transparent but also preserves images for eg. Why is this the case?
Image is preserved in every transparent material unless it possesses some additional symmetry e. But for disordered materials there is no such thing.
Glass is no different from e. It's not that an individual atom absorbs a photon and them re-emits it in the same direction; you can see this because only the interference between different atoms would lead to Snell's law of refraction.
I believe Feynman has an excellent explanation of this in his book QED, which I highly recommend as an elementary presentation of quantum mechanics. Diffraction, however, can be influenced by how the material is prepared. The boundaries between these regions are called grain boundaries.
If the distance between boundaries is smaller than the shortest wavelength of visible light in other words, if the refractive index of the material is uniform with respect to the light passing through it , then the material will appear transparent. Each boundary tends to diffuse the light that passes through; if the regions are small enough, however, the light waves essentially 'jump' right over them.
It has no internal grain boundaries, and hence it looks transparent. Solid silicon dioxide sand , in contrast, has obvious grain boundaries, so it is not transparent. One way to do this is to press a material under force, as is done all the time with potassium bromide, a compound used for infrared spectroscopy in laboratories.
The other way to achieve uniformity is to create lots of nucleation sites the locations where crystals begin to form in a melted material and then allow it to cool. Because many little crystals begin to form all at once, none of them can grow very large before they run into one another. The transparent Corningware sold today is made in this manner. It has the transparency of glass, but it is really a ceramic material similar to regular Corningware.
Newsletter Get smart. It changes direction many times and is scattered as it passes through. Therefore, we cannot see clearly through them; objects on the other side of a translucent object appear fuzzy and unclear. Because translucent objects are semi-transparent, some ultraviolet rays can go through them. This is why a person behind a translucent object can get a sunburn on a sunny day. Most materials are opaque.
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