![Focal length, explained by RP; focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius Focal length, explained by RP; focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius](https://www.rp-photonics.com/img/focal_length.png)
Focal length, explained by RP; focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius
![Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com](https://study.com/cimages/multimages/16/camerafocus.jpg)
Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com
![Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com Focal Length Formula & Examples | How to Calculate Focal Length - Video & Lesson Transcript | Study.com](https://study.com/cimages/multimages/16/2diagram_mirror6688182548421281944.png)