Methods of distance measurement?

[dave3141]

Update: I took 14 pairs of pictures of a line on a piece of paper a measured distance away from it.

I analysed the images and obtained offset of line from centre of image and used this to calculate the distance.

Basically I am getting between 5% and 10% error on each calculated distance compared to my measured ones.

I need help in figuring out how to calculate the size of the CCD, it states it as 1/1.7" but I have no idea what this means, so I have had to use someone elses calculation of CCD size, but I cant be sure if its correct.

I believe the width of the CCD to be 7.5mm, but this needs to be more accurate in my opinion as this could mean it's any where between 7.45 and 7.54.

I am currently using a Fuji S602Zoom digital camera for my experiments.

:?

 

[electroniks]

Update: I took 14 pairs of pictures of a line on a piece of paper a measured distance away from it.

I analysed the images and obtained offset of line from centre of image and used this to calculate the distance.

Basically I am getting between 5% and 10% error on each calculated distance compared to my measured ones.

I need help in figuring out how to calculate the size of the CCD, it states it as 1/1.7" but I have no idea what this means, so I have had to use someone elses calculation of CCD size, but I cant be sure if its correct.

I believe the width of the CCD to be 7.5mm, but this needs to be more accurate in my opinion as this could mean it's any where between 7.45 and 7.54.

I am currently using a Fuji S602Zoom digital camera for my experiments.

:?

You have to see what model is the CCD Chip, then go to the manufacturer's website or you have to call them (probably so) then 2 things happen; 1- they tell you this information violates trade secrets! 2- they will give you the information.
If 1, then you have to hack into it and go on the internet looking for people that used the same chip for image processing or such and see if they have done the calculations for you. if not you have to use pretty intensive math along with experimentation and MATLAB to find out exactly the size of the CCD.

 

[falmeshon]

another idea.
why not use lasers. One that hits the screen perpendicular and one at an angle. Then as you said, have a slide mechanism and line up the two laser dots. Instead of measuring the distance b/w the two lasers you could use a sliding potentiometer to measure resistance which will be proportional to the dist b/w the lasers. Obviously you need some sort of rudimentary rig for this.