Android DIY iPhone and iPad

How to Make a DIY Shoebox Projector for Your Phone

Christian Cawley Updated 15-06-2020

Sharing the display of your smartphone can be tricky. Wireless HDMI and mirroring are good options, but what if there is no TV screen to receive the signal?

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Well, you could turn your phone into a projector.

Yes, you read that right. And all you’ll need is a lens and an old shoebox. For less than $10 you can make a smartphone projector using items you might already have around the house.

Intrigued? Let’s begin!

How a Projector Works

Camera obscura is the basis for projectors

Building a DIY smartphone projector is not an original idea. Luckies’ Smartphone Projector, a cardboard flatpack system that you can build yourself, has been around a few years. This is basically a DIY version of that.

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Essentially, the device is a camera obscura—a black box with a hole in it and illuminated image within.

The camera obscura is one of the keystones of photography. An image can be projected through a small hole in a box or even room, and displayed on the opposite side, rotated 180 degrees. Without the discovery of this optical phenomenon, it is unlikely that photography and the photographic camera would have been developed.

Projectors use this principle, using a lens to rotate the image, hence righting the image so it can be viewed. The same is true for a cinematic projector, a home theater LCD projector, and any smartphone projector that you buy.

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But as these devices are basically a box with a lens, they’re easy enough to build at home. Let’s find out how to build a shoebox projector to use with an iPhone or Android smartphone.

Step 0: Things You Will Need for Your Phone Projector

To make an iPhone (or any smartphone) projector you will need:

  • Two boxes, one slightly smaller than the other.
  • A lens. This might be a magnifying glass or other biconvex lens—perhaps from another projector.
  • A method of positioning and securing your phone.
  • Black (or dark) duct tape or matte black paint and brush
  • Pencil.
  • Craft knife or similar cutting tool.
  • Suitable cutting surface.

Your boxes might be shoeboxes or perhaps tissue boxes. They should be similarly sized, with one small enough so that it can fit inside.

The sort of lens you will need for this project is a biconvex lens. These can be purchased from photography shops or online from specialist retailers, or even Amazon. They’re often bought as toy magnifying glasses.

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Step 1: Get an Idea of the Focal Length of Your Shoebox Projector

To project your smartphone display through the hole in your box, you need to consider the focal length. This is essentially the distance from the phone’s display to the lens.

Find a darkened room and switch your phone’s display to the maximum brightness. Place it on a table, around six inches behind your lens, pointing at a blank wall or pinned-up sheet of paper.

This should give you enough information to judge the size of boxes you will need. The rationale behind using two boxes is simple: you can adjust the focus by moving the lens.

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There is another advantage to this. The further the projector is from a surface, the wider the spread of light becomes. This means that big projections will be very dark in anything other than pitch darkness.

Step 2: Install the Lens in Your Shoebox Projector

To add the lens, first place it on the end of the box where you want to mount it and draw around it. Cut the hole with the craft knife, then repeat on the second box, ensuring the openings line up.

Cut a hole for your lens

Finally, use the duct tape to secure the lens.

Secure the lens with duct tape

Other options are possible. Hot glue, for example, will hold a lens in place, as might adhesive putty.

Step 3: Mount Your Phone in the Projector

With the lights low, it’s time to place your phone in the projector.

You might have chosen a box paring slightly narrower than the phone. In this case, cut a slot through both sides of the box where you plan to place the phone. It should slide into position and remain secure as long as is required.

Mount your phone in your smartphone projector

For wider boxes, find a way to attach your phone’s case to the back wall. This might require hot glue, or tape. You should then be able to simply snap your phone into the projector when you want to use it.

Step 4: Make the Projector Brighter With a Dark Interior

Most boxes are light colored on the inside. This will likely interfere with the quality of the picture, however.

To test this, place your phone in the box with the lock screen disabled and the brightness turned to full. With the lid replaced, turn the lights down and check the quality of the projected image.

You’ll find the image washed out, caused by the light bouncing around the inside of the box. To guide the light through the lens, make the box interiors dark. You might use a black matte paint, or black duct tape.

Make the inside of the projector dark

Neither is a quick solution, but duct tape doesn’t need to dry, so use this to save time. Whatever material you use, completely blacken the interior of your box. You can probably skip the area behind your phone.

Note that the duct tape will add to the interior width of the outer box slightly. While paint is a smarter option here, the tape can add some useful friction to the focusing mechanism.

Step 5: Set up Your Smartphone for Projection

You’re ready to test your build. Switch on your phone, slide it into position, and lower the lights.

Focus the picture and consider the results. You’ll almost certainly notice that the projected image is upside down—like the camera obscura.

How do you deal with this?

Invert Your iPhone’s Display

On iPhone, open:

Settings > General > Accessibility

Tap Touch > AssistiveTouch and set it to On

Now you’ll get a little white dot you can move around the screen. Tap it, choose Device then Rotate Screen and rotate the screen so that it is upside down when you place it in your projector. Finally head over to Settings > Brightness & Wallpaper and turn off Auto-Brightness. With this done, increase the brightness of your screen up to the maximum setting.

Use an App to Invert the Android Display

To rotate your Android’s display, use a third-party app. Several options are available in the Play Store, but they tend to be specific to a specific model of phone.

To find the best option, search Play for your phone plus screen rotate, e.g.: “galaxy s8 screen rotate.”

When you have your screen rotated by 180 degrees, you’ll need to ramp up the brightness. In Android, open Settings > Display > Adaptive brightness and tap the switch to disable. Next, drag the notification area down with two fingers and set the brightness control to full.

Step 6: Put Your Homemade Smartphone Projector Together

With the orientation issue fixed, you’re done. You’re the owner of a smartphone projector, built from boxes, for pennies.

For the best results, project onto a white screen in a completely darkened room. This might be to view Netflix; it could be YouTube. Whatever it is, be aware that the quality will be just good enough, rather than perfect.

You Built a Homemade Projector for iPhone or Android

You DIY smartphone projector should look like this

If you want a cheap projector you can only use at night, then this is the perfect project for you. The images are grainy, and slightly out of focus; it was never going to be perfect. However, there’s a certain amount of charm to it, and this smartphone projector makes an ideal science project.

Note that you don’t have to use two boxes, either. A single box will work, although you will need to spend more time positioning the phone. A lens from an old projector may work better here, secured with adhesive putty in the hole, ready to adjust the focus.

Like being able to project from your phone using a shoebox? Maybe it’s time to use a real projector. These budget projectors are ideal for smartphones The 6 Best Cheap Projectors for Your Laptop or Smartphone Buying a projector can be a pricey affair, but it doesn't have to be. Here are the best cheap projectors to help you out. Read More .

Related topics: DIY Project Tutorials, Mobile Accessory, Projector, Smartphone Tips.

Affiliate Disclosure: By buying the products we recommend, you help keep the site alive. Read more.

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  1. Arun
    August 23, 2017 at 6:58 am

    Why should we orient the image reverse in smart phone?then how it will project on the screen correctly?

  2. Chong Iskanda
    April 25, 2016 at 4:02 am

    Hmm how long does it take to make one unit?

  3. Suvam
    March 22, 2016 at 8:04 am

    I used a magnifying glass . But it didn't work. I am trying for 2 days but it is not working.Please please help me to resolve out this problem.

  4. Sofia
    February 21, 2016 at 8:35 am

    What is the purpose of painting the inside of the shoebox black?

    • Christian Cawley
      February 21, 2016 at 8:59 am

      TO reduce the spread of light inside the box. A black matt paint is perfect.

  5. Aditya Rai
    January 8, 2016 at 4:33 pm

    Please tell me more about the lens you use here? Which quality or diameter of lens is best or how many lens/es is/are required to get brighter image? Please tell me everything via this email ID - adityarai2727@gmail.com
    Thanks

  6. Affan
    January 6, 2016 at 7:40 pm

    Can we use a magnifying lens instead of biconvex lense.

    • harshal
      March 16, 2016 at 6:02 pm

      the bigger the better

  7. Muhammad Fahad
    November 26, 2015 at 7:58 am

    its work very well i got two different size projector lens which are perfectly working with my smart phone Huawei G750. if you use smart phone disable the auto rotate option and auto brightness and also put it on full brightness and adjust your smart phone colour temperature. two more things which were missing in that you can also insert the audio cable and charging cable for your device for long time running and good quality sound. do try this as well...

  8. Anonymous
    November 9, 2015 at 8:17 am

    I made the same with 90mm lens and using samsung smartphone,but unfortunately it is not working.i cannot see any clear image flashin on wall..can i know what should be the lens "mm" ??

  9. Anonymous
    September 25, 2015 at 8:09 pm

    i have tried this and working fine......:)))
    but i have some questions that is, is there is any chance to increase the brightness and invert the image?

    • Shafiku
      December 30, 2015 at 2:34 am

      You may need smaller than that....you should try 60mm or 50 mm

    • Aditya Rai
      January 8, 2016 at 4:31 pm

      Yes this is possible to invert the image - just lock your phone's auto rotation and invert it to 180° simply. And this is not possible to increase the brightness of your phone more than 100% because every phone is come with its own lamp watt and you can't increase it more than 100%.

  10. Tangodelta
    May 21, 2015 at 8:47 pm

    I think this is a great article and can't wait to make one.
    Thanks Christian!

    Also, if you don't have something nice to say then keep it to yourself.

  11. Nazeem
    April 5, 2015 at 12:24 pm

    Perhaps he wanted as many as clicks on is add! the heading is not suited!

    • Christian Cawley
      April 8, 2015 at 3:43 pm

      You do me and MUO a disservice. The title is absolutely accurate. It's in the DIY section, so it's here for you to try and learn from. If you don't want to try it out for yourself, then that's fine.

  12. Dmitry
    April 5, 2015 at 11:57 am

    Smartphone screen is not _very_ bright - so image will be dimmer by inverse square law even if we assuming that ALL light from the smartphone gets to the screen.
    So basically it's very cool project to do together with kids (though version with magnifying glass will be a bit more educational) but for practical use i'm very sceptical...unless one had suitable lenses laying around and suddenly need larger screen no matter how bad it is.

    • Christian Cawley
      April 8, 2015 at 3:42 pm

      Youre absolutely right, Dmitry, but I don't believe that it is up to us to suggest how you might use the project.

  13. Brian G
    April 1, 2015 at 9:21 pm

    Is it okay if I use black duct tape instead of black paint? Also, I have an old pair of eye glass lenses, I think I can attach each of them to either end of a tin can and put a see through mirror in the middle of the inside of the can to replicate the cine lens. This way I don't have to buy a lense or wreck a camera.
    Maybe next April 1 I will get everything together and make it for April Fools day 2016. Back to you in 2016.

    • Christian Cawley
      April 3, 2015 at 8:00 am

      This isn't an April Fool. As evidenced by the link to Luckie's Smartphone Projector on Amazon.

  14. Muhammad Uzair
    April 1, 2015 at 2:34 pm

    April fool article :-P

  15. CTownBOS
    April 1, 2015 at 10:27 am

    Spell check failed me. Article.

  16. CTownBOS
    April 1, 2015 at 10:26 am

    Title of artickle is more than misleading, it's wrong. It doesn't mention the most important part, the lens

  17. Christopher
    April 1, 2015 at 7:13 am

    The lens is the key and the author has brushed right past the most important part. The article should have gone into more depth for step #2; maybe by explaining how to build a projection lens with a couple of bi-convex lenses from eBay or an old pair of binoculars, etc.

    • Justin
      April 1, 2015 at 9:24 am

      Thank you. It really bothered me. At the very least give sources. :/

    • Christian Cawley
      April 3, 2015 at 8:01 am

      "The article should have gone into more depth for step #2; maybe by explaining how to build a projection lens with a couple of bi-convex lenses from eBay or an old pair of binoculars, etc."

      No. I conceived this post and decided what should be included and what not for anyone wanting to build a low-cost smartphone projector. Building a lens is clearly beyond the scope of this, and would have been a distraction.