Absorption

Question 1

What causes intrinsic absorption of UV light?

Answer 1

~ electron energy transitions

Question 2

How does intrinsic IR absorption occur?

Answer 2

~ resonance with atomic vibrations

Question 3

When does IR absorption in glass fibers increase?

Answer 3

~ it significantly increases above 1600nm

Question 4

What do impurities do?

Answer 4

~ (ex: transition metal ions) facilitate absorption bands via transitions between electron energy states

Question 5

What causes the absorption of OH- residing in the glass network?

Answer 5

~ induced by vibration of the OH- ions at 950, 1280, and 1400nm.

~ optical systems are designed to avoid these OH- peaks

~ OH- is pernicious to optical communication