I would take a look at products from Banner. I quickly checkedmy catalogs and
found one or 2 units that would likely fit the bill. Look at he SLM and SLC1
units. Website is www.bannerengineering.com. A lot of this will depend on
exactly what you are sensing. My experience has been that to get that tight a
registration tolerance, you need to be able to get the sensor about that same
distance from the object. This is typically the challenge we find in trying to
get discreet sensors to report that type of accuracy.



--- In Show-Control@yahoogroups.com, John Leonard <john@...> wrote:
>
> Folks,
>
> I'm trying to find a slotted optical switch that has a very small and
> accurate sweet spot. I've been testing the common or garden varieties and
> getting results that are too hit and miss for the project I'm undertaking. I
> really need an accuracy of 1mm between on and off states. I've played around
> with masking an existing switch, but if there's something that has a greater
> accuracy from the start, I'd be very interested to know. This is for a
> project where I cannot have anything connected to the device that is moving
> and providing the trigger.
>
> Thanks in advance for any information.
>
> John
>