Objective: Determine the focal length of a lens using the Bessel method
On an optical bench it is possible to set up a light source, a lens, a screen and an object to be imaged in such a way that a well focussed image appears on the screen. Using the geometric relationships between the ray paths for a thin lens, it is possible to determine its focal length.
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(230 V, 50/60 Hz), 1003312 [U33020-230], 供电器](/thumblibrary/U33020-230/U33020-230_01_140_140_直流电源0-20-V-0-5-A-230-V-5060-Hz.jpg)
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