Diffraction and Resolving Power

These flashcards cover key concepts related to diffraction and resolving power, as discussed in Lecture 31.

What is diffraction?

The bending of waves around obstacles or the edges of an opening.

What determines the resolving power of a lens?

The ability to distinguish between two closely spaced objects.

What was the Arab Eye Test?

An early eye test for resolving power where exceptional vision could see that Mizar was two stars very close together.

What is the Rayleigh Criterion?

Two point objects are just resolved when the first dark fringe in one object's diffraction pattern falls directly on the central bright fringe of the other.

What happens when two sources are widely separated?

They cast their own diffraction patterns, making it easy to tell them apart as they are completely resolved.

Define a diffraction grating.

An arrangement consisting of a large number of closely spaced, parallel slits.

What is the significance of the first minimum in resolving power?

It determines the resolution where the first dark fringe touches the central bright fringe of another object.

How do diffraction gratings produce an interference pattern?

By causing light to interfere constructively or destructively depending on differences in path lengths.

What is the general consequence of stopping down a lens?

It increases the resolution by reducing the diameter of the aperture, which decreases the minimum distance between two points that can be resolved.

What did Rosalind Franklin’s x-ray diffraction image reveal?

It helped reveal the crystalline structure of DNA.