calibration pixels to micrometers

[retroscience]

i have a waveform output of a picture.

the picture was a laser spot.

basically i took a picture, by using arrays i graphed a waveform of the picture.

but the waveform is in pixels and i want it in microns.

so i will need to calibrate it.

any tips?

- maryam.

[Norbert_B]

maryam,

i am sorry for not understanding what you are up to. The only thing i understand is your question: how do i get from unit pixel to unit microns?

Well, in optical measurements, it is common to calibrate the region of interest (roi) by using a special grid (see this link).

Maybe, you can use a similar technique for your purpose...

hope this helps,

Norbert 

Message Edited by Norbert B on 08-19-2008 04:55 AM

[retroscience]

hey norbert,

i have attached the vi.

you'll see the x-axis is in pixels, i want to convert this to micrometers.

[muks]

Can you post your code for lv 8.0?

[Norbert_B]

Your VI definetly lacks of documentation. It is totally unclear, what graph displays which data.

Besides, you are looking for two answers:

a) how can i change the unit pixel into unit micrometers in the display?

b) how can i calibrate 1 pixel into x micrometers?

The answer to b) cannot be given in the forum. You have to figure out own your own, how much micrometers are displayed as a single pixel. But please remind the following additional question: is it linear?

The answer to a) is simple: You can change display properties (names/units/max-,min-values are properties) anytime using the property node. But you have to keep in mind that this is only correct if you calibrate your pixeldata to micrometers before!

hope this helps,

Norbert