Calculate Antireflective Coating Thickness for Blue Light on Glass Lens

Thread starter Jodi
Start date Jul 11, 2005
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Light Nature Nature of light Wave

AI Thread Summary

To calculate the minimum thickness of an antireflective coating (n=1.35) for eliminating blue light reflections at 458 nm, destructive interference principles are applied. The formula used involves the wavelength of light in the coating and the refractive index. The required thickness can be derived from the condition for destructive interference, which typically is a quarter wavelength of the light in the coating material. This approach ensures that reflections from the top and bottom surfaces of the coating cancel each other out. Understanding these principles allows for effective design of antireflective coatings on glass lenses.

Jul 11, 2005

Jodi

HI; Could someone please help me with this question: Calculate the minimum thickness needed for an antireflective coating (n=1.35) applied to a glass lens in order to eliminate blue (458 nm) reflections for light at normal incidence? How would I go about this question? Thanks.

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Jul 12, 2005

Berislav

Use destructive interference.

Jul 12, 2005

Pengwuino

Gold Member

You should have a very very simple formula to figure this out.

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