Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Bloop asked in HealthOptical · 2 months ago

To focus parallel light rays to the smallest possible spot, should you use a lens with a small f-number or a large f-number?

A _____________f-number is required ___________.

Options:

small

large 

------

since the spot size decreases with the increasing focal length 

otherwise larger spherical aberration appears

otherwise larger chromatic aberration appears

since the spot size is proportional to the focal length and inversely proportional to the diameter

There are no answers yet.
Be the first to answer this question.