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abcd8989
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As shown in the diagram , why only ray 2 and 5 are considered? When ray 4 strikes the top interface from underneath, some is reflected. Why this ray is not considered?
Understanding Interference in Thin Glass: The Role of Ray 2 and 5 Explained
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In summary, only ray 2 and 5 are considered in the diagram because they produce the most visible interference pattern. Other higher order reflections may occur, but they are much dimmer and do not significantly contribute to the interference. Additionally, the phase shift for ray 5 and 5A is the same as 2 and 5, leading to constructive interference. However, this argument only applies to positive interference and for angles with negative interference, every second reflection has an opposite effect. These secondary reflections are typically weak, with subsequent reflections rapidly decreasing in power.
As shown in the diagram , why only ray 2 and 5 are considered? When ray 4 strikes the top interface from underneath, some is reflected. Why this ray is not considered?
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xts
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Of course, you may calculate higher orders (4 reflects, then travels parallel to 3 - call it 3A, then 3A reflects from bottom surface, making 4A ray, which then refracts to 5A).
Two issues:
1. every such reflection is much dimmer, than previous ones. So the interference pattern from the first order is the most visible;
2. phase shift 5-5A is exactly the same, as as 2-5. Constructive interference occurs when 2-5 phase shift is n*2π. For 5A you'll have 2*n*2π - still positive interference. But - to be honest - this argument works only for positive intereference! For the angles exhibiting negative interference, every second reflection acts opposite.
Two issues:
1. every such reflection is much dimmer, than previous ones. So the interference pattern from the first order is the most visible;
2. phase shift 5-5A is exactly the same, as as 2-5. Constructive interference occurs when 2-5 phase shift is n*2π. For 5A you'll have 2*n*2π - still positive interference. But - to be honest - this argument works only for positive intereference! For the angles exhibiting negative interference, every second reflection acts opposite.
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Claude Bile
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Secondary reflections are typically quite weak. Standard Fresnel reflections from air/glass for example is about 4-5% in power. The secondary reflections are then at most (0.05)^2 - 0.25% of the original wave. Subsequent reflections rapidly drop off in power.
Claude.
Claude.
1. What is interference-thin glass?
Interference-thin glass is a type of glass that has been specially designed for use in optical and scientific applications. It is a very thin and flat piece of glass that is used to create interference patterns when light passes through it.
2. What is the purpose of using interference-thin glass?
The purpose of using interference-thin glass is to manipulate light and create interference patterns that can be used for various scientific purposes, such as measuring the thickness of a material or studying the properties of light.
3. How is interference-thin glass made?
Interference-thin glass is made by coating a piece of glass with a thin layer of a material, such as magnesium fluoride, that alters the way light passes through it. This creates a thin film interference effect, which is what gives the glass its unique properties.
4. What are the advantages of using interference-thin glass?
There are several advantages of using interference-thin glass. It is very thin and lightweight, making it easy to handle and manipulate. It is also highly transparent, allowing for accurate measurements and observations. Additionally, it can be manufactured to have specific interference patterns, making it customizable for different applications.
5. What are some common uses of interference-thin glass?
Interference-thin glass is commonly used in scientific research, particularly in the fields of optics, physics, and materials science. It is also used in industries such as aerospace, electronics, and telecommunications for its unique properties in manipulating and detecting light. Additionally, it has applications in everyday items like camera lenses and smartphone screens.
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