Introduction: Build a Smartphone Projector With a Shoebox

Did you know you can turn an old shoebox and some office supplies into a Smartphone Projector? Yes you can! It is a fun, simple and easy physics experiment that you could do at home. Learn and observe how light


The project has been around the net for a long time, but here's a brief and detailed tutorial I made for everyone. (Most of my new videos will be made as brief and detailed as possible. Enjoy!)

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I'm back guys! During my very long absence of not posting projects here in instructables, I was shooting and compiling lots and lots of video tutorials to preserve the continuity of my new channel. Every week, I'll be posting new and random projects. So most of the Instructable tutorials that I will be posting, will start to have a video tutorial attached to it. Please do subscribe, if ever you are interested. Thank you! ^_^

Step 1: ​How Projectors Work

There are two major types of projectors in use as of this writing (things change pretty fast in the field). Projectors come with many features, strengths, or weaknesses, but most will run on either LCD or DLP technology. LCD is the older technology, but this does not mean that it is becoming obsolete by any means. LCD stands for Liquid Crystal Display. The way this places an image on a screen is fascinating and not nearly as complex as you might imagine. A bulb is set up to shine a fairly powerful light through a prism. The prism splits the light into its component colors and these are sent through small LCD screens. The screens themselves are sent signals to allow just so much of the light through at specific pixel locations. The light is then beamed through a lens onto a screen where the images can be seen by the human eye. DLP, or Digital Light Processing is a bit more complex. This time the light is shined through a spinning color wheel onto a chip that is mounted with hundreds of thousands of tiny mirrors. The mirrors are turned off or on by electronic impulses according to the need for the color at that moment. Even though only one color is shown at a time, one color follows another so quickly that the primary colors seem to blend into the appropriate color. The image appears to be constantly lit, when in fact small parts of it are constantly flickering. This technology was developed by Texas Instruments and is based on an older technology that was used for color television in the 1950s. Knowing the difference between these two types of projectors can be important, as LCD is considered better for static or high-contrast images. DLP, with its more vivid colors, is thought to be better for video. Some DLP projectors, have been known to manifest a rainbow effect. This can happen when white objects move on a dark background. Small shadows of red, blue, or green may be seen. Most modern DLP projectors have overcome this problem with multiple chips and higher rotation rates for the color wheel. So to what uses can we put these amazing machines?


This is not mine. This article was taken directly from: (source)

Step 2: Thing You'll Need


- Magnifying Lens

- Foam board

- Smartphone

- Gluesticks

- PVA Glue

- Shoebox



- Hobby Knife (XACTO)

- Hot Gluegun

- Cutter Knife

- Hacksaw

- Ruler

Step 3: Remove the Handle

Carefully use your hacksaw to cut off the handle of the magnifying glass.

Step 4: Reinforcement

Reinforce the box by gluing the flaps and corners of the box. This prevents it from wiggling.

Step 5: Let It Dry

Don't get too excited. Let it dry for a few minutes.

Step 6: Lens Placement

Position your box in an upright position. Place your magnifying lens on top then center it. Use a pencil to trace the cut line.

Step 7: Cutting the Perfect Round Hole

Here's a simple trick that I used all the time. If you are too OC, you can use an XACTO knife at the other end of a compass for cutting a perfect and round hole.

Step 8: Pop!

Push it, pop it!

- This is satisfying! Feels as if you were popping a bubble wrap. :)

Step 9: Position Your Lens

Position your lens before gluing the it in place.

Step 10: Glue the Lens in Place

Step 11: Cut Off the Protrusion

When you put the lid back on, the lid could block a portion of your lens (depending on the size of your lens or box). Use your precious cut out as a stencil then carefully slice off the excess cardboard that's blocking your lens.

Step 12: Build the Phone Stand

Build a phone stand using a foam board. Make sure it's perpendicular from the base to avoid image distortion.

Step 13: Tape Your Phone

Use a double sided padding tape to mount your phone on the stand.

Step 14: Set Your Phone

Set your phone to the highest brightness:

Simple, more light results to a brighter projection.

Don't forget to lock the screen:

The lens inverts the light source (your phone's LCD) to the projected image. This means you'll have to position your phone's screen in a topsy-turvy position in order to prevent it from auto rotating. Go set the lock-screen setting and disable the auto rotate.

Flip The Image: (optional)

Download an app that flips the orientation of the image.

Step 15: Adjust Your Projector

Like all projectors, this one needs to be calibrated too. Position your phone at the very end of the box then slowly move it closer to the lens, you will notice that the image will turn sharper/ softer. Move it back and forth until you get the sharpest projection.

Step 16: Turn Off the Lights - Watch in the Dark

Turn off your lights, wait for it to get dark then Enjoy!


Please do check my new YT channel: TechBuilder
If you like my past 4 episodes, feel to: Subscribe

I'm back guys! During my very long absence of not posting projects here in instructables, I was shooting and compiling lots and lots of video tutorials to preserve the continuity of my new channel. Every week, I'll be posting new and random projects.

Step 17: ​So Stay Tuned! There's More to Come!

TechBuilder Season #1 Includes:

- Minty Microphone Preamp

- Ultraportable Spud Canon! (This one's a killer. Promise! It's made from a stubby waterjug!)

- PVC Camera Slider

- Supercharge A Cheap Mini China RC Car (30,000rpm motor mod, Bluetooth Phone Control, LiPo, 30A ESC)

- Studio LED Lighting Panel (shown in the last few second of my projector video tutorial)

- Make A Cotton Candy Machine (using kitchen supplies)

- All You Have to Know About Greenscreening

- Funny Tissue Paper Dispenser Hat


This is the reason why I've been gone for so long. :)

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