Gadgets

How to make your own smartphone projector

Projectors - you don't need one, but you really want one. 

The good news is, you don't have to splash out a few hundred quid for wall-illuminating media kits. In true Blue Peter fashion, you can make your own projector with a smartphone and a few odds and sods.

No, it's not going to compete with a 'proper' projector - but it's a neat addition for that house party you were planning. 

What you need

- A cardboard box, ideally a shoe box with a tight-fitting lid

- A craft knife

- Large and small bulldog clips

- LEGO/A large paperclip

- Tape

- A magnifying glass, around 10cm in diameter

- A glue stick

Ready your box

Yes, that is an immature title - but you're going to need to cover every hole and gap in your chosen box. Make sure no light can get in or out. 

In one end of the box, you're going to want to make a circular hole a little smaller than your magnifying glass. Ideally, you'll want to pop the lens out of the glass (the handle will just get in the way), draw around it, and then cut slightly inside the line with your craft knife. You'll then want to glue the lens to the inside of the box, aligning it with the hole.

If you plan on watching films with the projector, you might want to cut a small hole in the side of the box to thread your charging cable through.

Make a stand

Not a political one, but rather something to stand your smartphone up horizontally inside your box. This is where the LEGO or paper clip comes in. 

If you're using LEGO, try building something that will see your smartphone stand upright without a hint of tilt. Likewise, unfold the paper clip and try bending it into different shapes - a simple solution is straightening out the wire, folding it into a right-angle and punching each exposed end through the bottom of the cardboard box to create a triangle.

Have a play.

Ready your phone

To ensure your projector emits a viewable image, you're going to want to tweak some settings on your smartphone.

Foremost, you're going to need to flip the image - else it'll appear upside down after passing through the lens. You should be able to find this option in the 'Accessibility' section of your phone's settings menu - or try downloading a flip app, like this one.

Next, boost your screen brightness to the max. If you've got a wireless speaker, be sure to connect that up as well.

Finally, you'll need to play around with adjusting the focus of the image. To do this, line your box up with the wall you want to project onto, turn off the lights, and - starting with your phone next to the lens - slide your phone (and its stand) toward the back of the box. At some point, the image on your wall will become clear. Mark this position in the box with a pen, pop the lid on and you're off.

For more help, try this brilliant free guide from Mat Bothell on Instructables.