Being "black" is not enough. It should be black in IR wavelengths.
But really, if you use one of the "C" shape sensors that have the emitter and receiver built into one housing the beam is 10X smaller than your slots reflections and such don't matter. What will mess you up is if the IR beam is so broad that it illuminates three slots at the same time. Then you get "multi-path" but that is easy to fix. I have this little mobile robot chassis with motors that use slotted white plastic disks and IR optical sensors to measure and control wheel speed. It is not even shielded from ambient light and the $1 "C" shape sensors give clean signals. On Mon, Aug 24, 2020 at 4:33 PM jrmitchellj <[email protected]> wrote: > Since your tacho disk still has some thickness to it, you may get > reflections off the inside edges that could make the transitions "unclean". > > --J. Ray Mitchell Jr. > [email protected] > > > > "Good enough is the enemy of excellence"author unknown > > > On Mon, Aug 24, 2020 at 12:38 PM John Dammeyer <[email protected]> > wrote: > > > > From: jrmitchellj [mailto:[email protected]] > > > Have you considered blacking the part? Either anodizing or flat black > > > paint? > > > > > > --J. Ray Mitchell Jr. > > > [email protected] > > > > Why would I want to do that? > > > > The bottom that you cannot see is actually already black since it was the > > outside part of the TEC86 computer front panel. The back surface is > > actually clear anodized by the looks of it. > > > > John > > > > > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
