DIY Laser levelling using webcam and laser level

[John McNamara]

Hi All

As some of you may know I am interested in using a stretched very fine .008" piano wire to determine straightness using a microscope.

I posted my thoughts through this post here on this site. http://www.mycncuk.com/threads/12534...-and-reference

Subsequent to those posts I found an excellent thesis written by Boris Borisov

"New optical sensing system applied to taut wire based straightness
measurement". Doctoral thesis, University of Huddersfield.

http://eprints.hud.ac.uk/id/eprint/2...inalthesis.pdf

I was quite surprised that the accuracy of high end industrial lasers was inferior to the optically sensed stretched wire method he developed over longer distances >2m. See the graph on page 28 of the thesis.

Even more surprising was the simple sensor he used, Omron EE-SX1096 and EE-SH3 photomicrosensors Cost about 2 dollars on ebay!

This is definitely something I want to try. The levels of accuracy he has achieved are outstanding; a few um.

Regards
John