Wavelength nature of light: magnesium Fluoride

In summary, the conversation is about determining the minimum thickness of magnesium fluoride coating needed to make a glass lens non-reflecting for a specific wavelength. The formula t=[lamb]/4n is used, but there is confusion about whether the minimum thickness is non-zero or zero. Ultimately, it is clarified that the minimum thickness is non-zero and there may have been an error in calculations.
  • #1
Dx
Hi!

In terms of magnesium fluoride what is the minimum thickness of mag fl coating that must be applied to a glass lens to make it non-reflecting for that wavelength? (the index of refraction of magnesium fluoride is intermediate to that of air and glass)

1/2 wavelength out of phase to eliminate reflection. why is this wrong? I usd the formula t = [lamb] / 4n. I used the minimum thickness (m=0) since the destructive interference will occur over the widest angle. Plz help? Or it this a trick question and there is no minimum thickness, huh?
Dx :wink:
 
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  • #2
Originally posted by Dx
I used the minimum thickness (m=0) since the destructive interference will occur over the widest angle.

Obviously, they mean the minimum nonzero thickness. "Zero thickness" means that there is no film at all.
 
  • #3


Originally posted by Tom
Obviously, they mean the minimum nonzero thickness. "Zero thickness" means that there is no film at all.
Its not that obvious Tom since that's not one of the answers. I understand what your saying so I need to figure out the different wavelengths then, huh?
Dx :wink:
 
  • #4
Originally posted by Dx
why is this wrong? I usd the formula t = [lamb] / 4n. I used the minimum thickness (m=0)
Dx :wink: [/B]

You are right. The minimum thickness of the coating is given by t=[lamb]/4n. I think you did an error in calculations. Check it please.
 
  • #5
Originally posted by Dx
I usd the formula t = [lamb] / 4n. I used the minimum thickness (m=0) since the destructive interference will occur over the widest angle.

OK, sorry. I didn't know what m was, and I thought you chose the thickness to be zero.
 

FAQ: Wavelength nature of light: magnesium Fluoride

1. What is the wavelength nature of light?

The wavelength nature of light refers to the fact that light is made up of electromagnetic waves with different wavelengths. This means that light can be described as a spectrum of colors, with each color corresponding to a specific wavelength.

2. How does magnesium fluoride affect the wavelength of light?

Magnesium fluoride is a material that is commonly used in optical coatings and lenses due to its ability to manipulate the wavelength of light. When light passes through magnesium fluoride, the material absorbs certain wavelengths and reflects others, resulting in a change in the overall wavelength of the light.

3. Can magnesium fluoride block specific wavelengths of light?

Yes, magnesium fluoride can be used as a bandpass filter to block specific wavelengths of light. This is because the material has a high refractive index, meaning it can effectively block certain wavelengths while allowing others to pass through.

4. How does the wavelength of light affect its properties?

The wavelength of light directly affects its properties, such as color and energy. Shorter wavelengths correspond to higher energy and blue or violet colors, while longer wavelengths have lower energy and red or orange colors. In addition, the wavelength of light also determines how it interacts with different materials, such as how it is absorbed or reflected.

5. What is the relationship between wavelength and frequency of light?

Wavelength and frequency of light have an inverse relationship, meaning that as the wavelength increases, the frequency decreases and vice versa. This is described by the equation c = λν, where c is the speed of light, λ is the wavelength, and ν is the frequency. This relationship is a fundamental concept in the study of light and its properties.

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