Discussion Overview
The discussion centers on the application of the Beer-Lambert law in calculating the intensity of transmitted light through a medium at non-normal incidence, specifically at an angle of 45 degrees. Participants explore the interaction of light with a thin film of aluminum on a glass substrate, considering both reflection and absorption.
Discussion Character
- Technical explanation
- Mathematical reasoning
- Debate/contested
Main Points Raised
- One participant seeks to determine the proportion of intensity lost due to reflection when light hits a thin aluminum film at 45 degrees.
- Another participant suggests using the Fresnel equations to calculate the reflected light, emphasizing the need for the complex index of refraction of aluminum.
- A participant inquires whether to use the real index of refraction for reflectivity calculations and the complex part for attenuation calculations.
- It is noted that reflectivity is influenced by both the real and imaginary parts of the index of refraction.
- A participant calculates a reflectivity of 93% but questions the applicability of this value considering the film thickness.
- Another participant acknowledges the calculated reflectivity and suggests using the Beer-Lambert law to determine the intensity reaching the lower surface of the film, factoring in reflectivity again for the final intensity in the glass.
Areas of Agreement / Disagreement
Participants express differing views on the appropriate use of the Beer-Lambert law and the Fresnel equations in this context. There is no consensus on the implications of film thickness on the calculations or the feasibility of light transmission through the aluminum film.
Contextual Notes
Participants highlight the complexity of the problem, noting the dependence on the thickness of the film and the angle of incidence, as well as the need for accurate values of the complex index of refraction.