A glass slab of re \fractive \fractive \fractive index μ g \mu_{g} μ g =1.44 is coated with a thin film of re \fractive \fractive \fractive index μ f \mu_{f} μ f =2. Find the minimum film thickness for maximum transmission of normally incident green light of wavelength 5000 Å.
Physics · Wave Optics · interferece of light and huygen principle
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Question

A glass slab of re \fractive \fractive \fractive index μ g \mu_{g} μ g =1.44 is coated with a thin film of re \fractive \fractive \fractive index μ f \mu_{f} μ f =2. Find the minimum film thickness for maximum transmission of normally incident green light of wavelength 5000 Å.

Physics · Wave Optics · interferece of light and huygen principle

G1 Physics · Accepted Answer

Using the condition in the supplied solution, 2μ_f t=nλ. For minimum non-zero thickness n=1, t=λ/(2μ_f)=5000×10⁻¹⁰/4=1.25×10⁻⁷ m=0.125 μm.