Ultrasonic sensor with range down to 1mm

Hi,
I'm new to arduino and I would like to know which sensor (e.g. ultrasonic) I can use for detect down to 1mm range distance.
my main project is to detect the disturbance in a surface metal sheet and the offsets are in 1mm range and the maximum is up to 10meters (..most cases up to 2meters).

thanks for your help

Some one had a link to o e here the other week. It is not cheap about $400 and gets the resoloution by running at high frequency. I have the link on another computer if you want I could post it in an hour or so.

thanks for your reply, yes if you can post the link it would be great.

is there any alternative less cheaper than 400$, let's say range of 100$.

thanks again.

http://www.sick.com/group/EN/home/products/product_portfolio/distance_sensors/Pages/ultrasonic_sensors.aspx

is there any alternative less cheaper than 400$, let's say range of 100$.

Precision = commercial devices, these are not toys.

HI, if you are looking at 2m down to 1mm, I think you are going find it hard to find what you want.
There is a trade off between range and resolution, the basic SICK spec may say up to 8m but that is not down to 1mm resolution and minimum range.

Interesting to see what you find, SICK are probably one of the best in the sensor field, I suggest you email them with your requirement and see what comes back.
I have used their laser distance products and had no problems.

Tom..... :slight_smile:

Hi Tom,
can you please advice me what Laser sensor you've found helpful for such range from 1m to 1mm?

regards
sergey

whit avr i get a number around 500.xxxxx and it changes when i change surface less than mm but not accurace i think:) i guess that would be expensive! u should find another way!

You need to express your requirement more clearly. Do you want to measure something which is 1 mm away from the sensor ? Or do you want to reliably distinguish between something which is 200 mm and something which is 201 mm away from the sensor ?

michinyon:
You need to express your requirement more clearly. Do you want to measure something which is 1 mm away from the sensor ? Or do you want to reliably distinguish between something which is 200 mm and something which is 201 mm away from the sensor ?

Hi,
What i need is the second part of your question, distinguish between 200mm and 201mm.