CD Track problem, Lense and laser

[Synetos]

Hi,

I have a problem with an optics experiment, the experiment involves measuring the interference patterns created by the tracks of a CD.
But as soon as I put a lense in between we get an really odd pattern, this pattern seems to not move along with the laser as the beam is being shifted (by moving the lense) and thus we think that this might be the the tracks which are magnified but this would mean that they are magnified over 2000X (which is weird)

Does anybody know what how or what this is?

(will post pics and vid soon)

 

[eljose79]

Hi there,

Thank you for sharing your experiment and for asking for help. It sounds like you are experiencing some unexpected results with your optics experiment involving CD tracks and a lens. Without seeing the pictures and video, it is hard to determine exactly what is happening, but here are a few possible explanations and suggestions to try:

1. It is possible that the lens you are using is not the correct focal length for your setup. This could result in an enlarged or distorted image of the CD tracks. Make sure to double check the specifications of your lens and compare it to the distance between the lens and the CD.

2. Another possibility is that there is some sort of defect or imperfection in the lens itself, causing it to create strange patterns. Try using a different lens or cleaning the one you have to see if that makes a difference.

3. It is also possible that the laser beam is being scattered or diffracted by the CD tracks, causing the interference pattern to appear distorted. This could be due to the quality or thickness of the CD tracks. You may want to try using a different CD or adjusting the angle of the laser beam to see if that helps.

I hope these suggestions are helpful and that you are able to troubleshoot and resolve the issue. If not, please feel free to post the pictures and video so we can better understand the problem and provide more specific advice. Good luck with your experiment!