Hello! This time i am here with a small mini projector just out of $3 . This is a very fun project to make and pretty easy to make.You need to switch off the lights and watch the action! It is powered by a mobile phone or any digital media player.It's quality is very good if you will use a good phone with full brightness and high contrast. The better the brightness and contrast is the better is the projection. The mobile i've used here has very less features and my dad won't allow me to do this with his expensive phone so i have to use a bad one with bad quality , very less brightness and contrast but i assure you if will use a good bright mobile phone with good brightness control you will get very good quality! I can't show you it's working image because i don't have a mobile with a bright screen and my camera is not catching that much low light but i assure you it's visible! I f you are not getting that quality tell me what problem you are having!

Step 1: Technical Details.

This projector works on the principle of magnification. The brighter the image from the source is the better is the quality of projection.The source should be held upside down or the projector box should be upside down to get a correct image on the canvas.The room should be kept dark. The distance between the source(the mobile phone) and the lens should be adjusted (Keeping the distance between lens and the canvas constant means)accordingly to get a non blurry image on the canvas. The words or the alphabets will be right side left.

Step 2: Grab Stuff!

Once you had decided to make one of your own you need to grab some general stuff!

1. Get The lens (You have to open a old film camera out of scrap!)

Take the camera.
Open the casing.
Remove the lens by screwing out the screw.
Now you have the lens.

2. A card board

3. Hot glue gun.

4. A pair of Scissors

5. Blade

6. Opaque Tape.

7. Pencil and other stationary.

8. A big white canvas.

9. A good mobile phone.

Having Adjustable brightness.
200 ppi Screen (You can still use a bad quality but it will be better to use a good one.)
Having Adjustable Contrast & Color.

Step 3: Making!

Now here is the step by step description of the build!

1. Take a piece of cardboard and mark two rectangles on the cardboard with pencil according to you mobile phone's dimension

2. Now cut them out with scissors.

3. Now cut one10cm wide and xcm (xcm refers to the width of your mobile phone) long rectangle from the cardboard it will be used as the base of the projector.

4. Now make a whole box using hot glue or other adhesive by making the out two side but you have to leave one side which faces the front side of the your mobile phone.

5. Take the side which is left and mark a circle according to the lens radius at a place which face the middle of the screen of your phone (i have marked it little bit on the left side because my screen's center if at the left side.)

6. Cut the hole with blade and fit the lens there and stick that side with the box now.

7. Tape the edges so that any light comes out.

7. Now check the quality you are ready now just the lid and the adjustment is needed.

8. Now you can see in the image marked as (show1) that the quality is not good sobring the mobile close to the lens and put the projector away it will improve the quality.

9. Now paint the projector and do whatever you wanna do!

NOTE: Put you phone at the brightest mode and highest contrast before using it with projector.

Step 4: Author Tips.

1. The room should be dark where you are going to use the projector.

2. The lens should be clean.

3. It's ideal for watching movies.

4. The brightness should be at maximum level.

5. The colors should be set to vivid.

6. The contrast must be high.

7. Slow after some tests you will learn how to make adjustments of the distances.

Thank you for going through my project! If you have any doubts you can make a message.