I need the small spot size of the measurement. I imagine US is not that well defined.
> On Mar 7, 2022, at 2:32 PM, jeanfrancois <jfsimon1...@gmail.com> wrote: > > Are ultrasonic sensors doing the job in that tolerance ? > > Jean-François > > > Le 07/03/2022 à 21:01, gene heskett a écrit : >> On Monday, 7 March 2022 12:44:21 EST Thaddeus Waldner wrote: >>> Hi, >>> >>> I’m looking for a laser distance sensor with about 1-3 thousandths >>> resolution and about a 5-10” working range. I wouldn’t mind buying a >>> used unit. >> 1. I didn't know they came in that high a resolution w/o needing a quorum >> of the US Senate to authorize the payment, then signed by the President. >> >> If you want to know why, calculate the time difference of that 3 >> thousandths of an inch increment, remembering that it has to travel out, >> and back to the measuring device, equal to C/2 in speed. You will I >> suspect will come up with a very small fraction of a picosecond. >> >> Interferometry can measure that change, but the mod function to detect >> the individual null and count it has to start at zero, or a known micron >> sized distance before it can count the nulls passing by as it moves from >> zip distance, back to your point of interest at a 12" max range. Moving >> slow enough to count, will take a 2048 bit counter and several days. >> >> Technically, we can do it but you'll need a couple of dump trucks full of >> gold to finance one neasurement. We can't yet buy a calibrated answer in >> 10 milliseconds for a $500 bill. Someday? Maybe, but it may take a new >> method to be invented. >> >>> Does anyone here know of some brands/ models to check out? >>> >>> Google has pointed me at some Acuity products but I wondered if there >>> were other options besides that. >>> >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >> >> Cheers, Gene Heskett. > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users