Thin Film Problem: Find Minimum Thickness for Light Transmission

  • Thread starter Thread starter physicist10
  • Start date Start date
  • Tags Tags
    Film Thin film
Click For Summary
SUMMARY

The discussion centers on calculating the minimum thickness of a thin film with a refractive index of 1.50, coated on glass with a refractive index of 1.33, to achieve optimal light transmission at a specific wavelength (λ). The key concept involves understanding the phase difference of light reflected from the film's upper surface, which is crucial for determining whether constructive or destructive interference occurs. For maximum transmission, constructive interference must be achieved, indicating that the film's thickness must be a quarter of the wavelength of light in the film medium.

PREREQUISITES
  • Understanding of refractive indices and their implications in optics
  • Knowledge of interference patterns in light waves
  • Familiarity with the concept of phase difference in wave mechanics
  • Basic principles of thin film optics
NEXT STEPS
  • Research the formula for calculating thin film thickness for constructive interference
  • Learn about the effects of varying refractive indices on light transmission
  • Explore the principles of phase shifts upon reflection in thin films
  • Investigate practical applications of thin film coatings in optical devices
USEFUL FOR

Students in physics or engineering, optical engineers, and anyone interested in the principles of light transmission and thin film applications.

physicist10
Messages
17
Reaction score
0

Homework Statement



A glass (Refractive index 1.33) is coated with a thin film. (Refractive index 1.50)

Find the minimum thickness of the film, if the glass is to transmit light of wavelength λ.

Homework Equations



The Attempt at a Solution



Light reflected from the upper surface of the film will suffer phase difference. That's all I know about this problem. Are we looking for constructive interference or destructive interference?
 
Physics news on Phys.org
No help?
 
It sounds like they probably want 100% transmission, so constructive interference for transmission, destructive for reflection.
 

Similar threads

Replies
7
Views
6K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
3
Views
3K
Replies
1
Views
3K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
5
Views
8K
Replies
2
Views
4K
Replies
2
Views
2K