Optics - Spectacles lens Power Estimation

AI Thread Summary
Chaitanya proposes developing a mobile app to estimate the power of spectacle lenses using a smartphone camera. The method involves capturing an image with a lens positioned to cover half of the frame, creating a disparity in focus. Key challenges include accounting for variables such as the distance between the lens, the object, and the camera. It is suggested that user instructions for fixed positioning could enhance measurement accuracy. The discussion highlights the potential for image processing techniques to achieve this goal.
Kaycee92
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Hi,

I'm Chaitanya, 4th year undergraduate student in biomedical engg.

I have an idea of making a mobile phone application which measures the power of your spectacle glasses.

The idea is we take an image with the phone's inbuilt camera. One of the spectacle lens will be held in front of the camera such that it covers roughly half of the image.

In this way, one half of the image (lens half) will be nearer than the other half.

So, my questions are:

1. Can I do some image processing and give an estimation of the power of the lens?

2. How much time could this project take?

Thanks,
Chaitanya.
 
Science news on Phys.org
Glasses do more than shifting the effective distance of an object - and their influence depends on their distance to the object and the distance to the camera, two unknown parameters. In addition, modern glasses often have more than one parameter.

It is possible to measure those parameters with test images with/without lenses in between, I did this as lab course (just more astronomy-related), but this used special hardware. It should be possible without, too.
 
Maybe we can instruct the user to place the object and the camera at some fixed distance. This might help in getting an accurate reading.

I'll go through that adaptive optics page and get back to you.

Thanks a lot! :)
 
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