Methods for Measuring Focal Length of Optical Elements
Explore various methods for accurately determining the focal length of optical elements, including quick estimation, neutralization tests, Geneva gauge, nodal slide techniques, reciprocal magnification derivation, and the Point Source Microscope (PSM).
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
Methods of measuring the focal length of the optical element Yu Yan
1 Quick Estimation 2 Neutralization Test 3 Geneva Gauge 4 nodal slide 5 Reciprocal Magnification Derivation 6 Point Source Microscope(PSM)
Cardinal points and planes Nodal planes have the characteristic of identity angular magnification. When the optical system is in air, nodal points/planes coincide with the principal points/planes.
Quick Estimation One easy way to get a rough lens focal length is to hold it under a ceiling lamp and use the testing optical element to form a image of the ceiling lamp. The optical element is moved vertically back and forth until a sharp image of the ceiling light is projected on the floor(table surface or other things that can be used as a screen). The distance between this element and the floor is focal length.
Geneva Gauge ? =?2+ ?2 2?
Reference http://www.medrounds.org/optics-review/2006/05/39.html John E. Greivenkamp, Field Guide to Geometrical Optics , SPIE Press, 2004.
