This preview shows pages 1–4. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Ch 32 Reflection and Refraction L23 Focus: “Ray” Optics approximation—neglecting diffraction “Image” is located where rays appear to come from Refracting surfaces HeNe Laser b θ Find θ ( b ) as precisely as possible. For a given Δ b b Δ = Δ λ θ θ λ θ λ >> Δ ≈ Δ >> b b min θ λ θ ≈ >>> b Scale of b = lens diameter Δ b aperture want θ >> Δθ and b >> Δ b For “Ray” optics, Condition for “Ray” Optics If all angles are large compared to the diffraction angle, the ray optics approximation is valid. Ch 32 Reflection and Refraction L23 Images formed by Flat Mirrors P Object h Image is as far behind mirror as object is in front. No leftright reversal, only frontback reversal. Lateral Magnification: 1 ' height object height image = = = h h M Upright image M > 0. Virtual Image: No light is actually coming from here! h ’ But, rays appear to come from here. Ch 32 Reflection and Refraction L23 Total Internal Reflection : Fiber Optics n 1 n 2 θ 1 Snell’s Law: n 1 sin θ 1 = n 2 sin θ 2 For n 1 > n 2 there will be a critical θ 1 = θ c where θ 2 = 90 o and sin θ 2 is maximum = 1....
View
Full
Document
This note was uploaded on 05/13/2010 for the course PHYSICS 54L taught by Professor Thomas during the Spring '09 term at Duke.
 Spring '09
 Thomas
 Physics, Diffraction, Reflection And Refraction

Click to edit the document details