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I have the "Mpow Projection Alarm Clock" (https://amzn.to/2VtA1Cx) and although in the example image the time projected on the ceiling is gigantic, in reality it's only about 7 inches (18cm). It's still small when I project it on the other side of the room (I have a small room). I want it to be much bigger.. Ideally triple the size.

I tried holding two kinds of magnifying glasses at various distances over the thing where the time is projected out and that doesn't work. The projected time turned into an unreadable circle. I tried a camera lens and perhaps the projection isn't bright enough because nothing was visible - no light was coming through.

  • According to the product description, the image is designed to project up to ten feet from the projection clock. – Stan Apr 8 at 22:24
  • You'd need to move the original lens (focus) closer to the internal display when using an added positive lens. – DrMoishe Pippik Apr 8 at 22:32
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If you have mirrors in the room, you could bounce the projection off the mirror on one side of the room and then read it off the wall on the other side of the room. This should get you up to 14 inches.

However, the image will be reversed. If you have two mirrors the image could be corrected and you could have a final size of 21 inches.

CAUTION: The larger the projection, the dimmer it will be. I don't know if it will still be readable after enlarging it with the mirrors.

  • The ad mentioned that the image can be flipped with a built-in adjustment as well as the ability to swivel the image somewhat. – Stan Apr 10 at 15:18
  • @Stan: Hi Stan. It says the projection can be flipped "upside down 180". I don't think that will create a mirror image. – James Apr 10 at 15:32
  • Mirrors can be used to flip (or flop) an image depending on the angle. If the clock is put in front of a mirror and the image is projected to the ceiling from the bounced image, it will be flipped top-to-bottom. If the image is bounced from the front toward another wall, the image will be flopped left-to-right. This is why you see a "mirror image" when looking straight into your bathroom (for one example) mirror. The practical limit of the image distance from the lens will determine the sharpness of the image. The existing optics will allow up to a 10 foot throw before becoming fuzzy. – Stan Apr 10 at 16:28
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    Does there not exist an anti-magnifying glass? e.g. there are concave mirrors used as makeup mirrors and convex mirrors used for seeing a wider angle. So shouldn't the opposite also exist for magnifying glasses? – Aaron Apr 15 at 14:23
  • @Aaron: Yes there are. A magnifying glass is a "convex lens". The opposite is a "concave lens". For examples lens for sale, search for "concave lens" on Amazon.com – James Apr 15 at 14:46

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