Do you use a PIR sensor? How do you hide it?



  • I’ve read that a PIR sensor can work out of a 2mm hole. So if you just drill out a cavity for the sensor to sit in and then drill a 2mm hole out the front of the frame that would work.

    Except there is that small problem (pun not intended) of the 2mm hole in the middle of your frame. I guess it would look a lot like the holes you see at the top of some laptop monitors. Then if you stain the wood with a dark color the hole might not be too noticeable.

    But I’ve also heard people talking about putting a pinhole camera or (I think it was) a radar module “behind the glass”. How on earth do you do that? I mean, the monitor is behind the glass so unless you leave a sizable gap between the acrylic and the monitor there’s no way anything will fit back there.

    Sadly, the pinhole option seems like the best to me. But do you know of any better way to do it?



  • @boblazer i haven’t done mine yet… but to put behind the glass you need additional space around the screen of course…

    then mount on some wood/etc, with black cardboard or whatever and have the pinhole there, or whatever the sensor needs… nothing magic…

    some sensors don’t work behind…

    my PIR board looks like it needs a little over 1/4 in for the sensor hole, measured at 8mm,
    maybe you only need 2mm of that to make the sensor work…



  • @sdetweil said in Do you use a PIR sensor? How do you hide it?:

    maybe you only need 2mm of that to make the sensor work…

    Yeah, that’s my understanding. I can’t find the post but it was here on this site. A guy did some experiments to find the smallest size hole his PIR sensor actually required. He tried 1mm, 2mm and 4mm(?). He said it worked just fine with a 2mm hole.


  • Moderator

    @boblazer said in Do you use a PIR sensor? How do you hide it?:

    @sdetweil said in Do you use a PIR sensor? How do you hide it?:

    maybe you only need 2mm of that to make the sensor work…

    Yeah, that’s my understanding. I can’t find the post but it was here on this site. A guy did some experiments to find the smallest size hole his PIR sensor actually required. He tried 1mm, 2mm and 4mm(?). He said it worked just fine with a 2mm hole.

    You are referring to this one: https://forum.magicmirror.builders/topic/557/pir-sensor-behind-glass/33


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  • @yawns Yes! Thanks.



  • @qu1que Having other lights there like you do makes it fit in a little better. That’s something to think about. Maybe I’m trying to make mine look too old-fashioned.



  • I made a 8 mm hole on the backside and a 2 mm hole on the frontside.
    Removed the cap from the motion sensor and placed it in the 8 mm hole.
    Works great and you can hardly see the 2 mm hole.

    Backside:
    alt text

    Frontside:
    alt text



  • Nice pic, thanks for showing us how it actually looks.

    It still bugs me though. Looking at yours I wonder if putting a power light (or something light) next to the PIR hole would make the PIR hole look like less of a forced design choice. You know, it could even be a chiche looking light that blends into the wood and lights up in such a way that it doesn’t make the mirror look tacky and also doesn’t give you the feeling that it’s like a monitor power light.

    I don’t know what that would look like. Not super bright. Maybe kind of dull but not so dull that it looks weak. Maybe a good complimentary color to the wood. Maybe not a circle or a rectangle but a cool shape like a rhombus. Maybe you could put a logo or text of some sort on the face of the mirror and hide the hole there and it wouldn’t look out of place.



  • I still have to paint the frame, thinking of a kind of ‘white-wash’ so you keep seeing the wood grains. Maybe it’s less ‘obvious’.
    But you know and I know, but most visitors I’ve had didn’t even see it or looking for it 🤔