Problem 15Q

By what factor can you improve resolution, other things being equal, if you use blue light rather than red (700 nm)?

Step-by-step solution

Step 1 of 1

It is known that Blue light wavelength =

Red light wavelength

When the two objects are at distance D apart, the limit of resolution can be obtained from the Rayleigh criterion:

, which can be interpreted as the smaller the angle, the better resolution.

Therefore, the resulting angle for blue light is:

Hence resolution with blue light istimes the resolution with red light.