How do I make a movie projector

Tinkering a projector: It's that easy!

In this manual, the GEOlino workshop shows you how to make a projector out of a shoe box. This will transform your room into a real cinema!

To make the projector you need:

  • Shoebox
  • Magnifying glass
  • black acrylic paint
  • brush
  • black electrical tape
  • pen
  • cutter
  • 40 cm solid wire (or clothes hanger from cleaning)
  • Combination pliers
  • scissors
  • 2 A4 sheets of paper
  • Adhesive tape

This is how the projector is tinkered:

1: Hold the magnifying glass in the middle of a short side of the cardboard and draw the outline on it. Use the cutter to cut the circular one opening out. Cut a small slot on the opposite side of the box for the smartphone's charging cable.

2: Paint the whole box including the lid from the inside with the black one Acrylic paint out. This will prevent unwanted light reflections later. Let everything dry well.

3: Stick the magnifying glass exactly into the hole with the insulating tape. Do you want to leave the handle of the magnifying glass on? No problem: the whole thing sticks Magnifying glass fits exactly in front of the hole. Glue everything tightly on both sides with insulating tape so that no light shines through the glue point.

4: Now you need a holder for your smartphone so that it stays upright. To do this, take a piece of wire and use the combination pliers to bend it into one holder Rightly - which should look something like the picture. A wire clothes hanger is also easy to bend.

The structure: This is how the room becomes a cinema

  1. Darken yours room - it really has to be very dark.
  2. Glue two as canvas leaves white A4 paper next to each other on the wall.
  3. Provides the brightness on the smartphone to 100 percent (i.e. maximum brightness).
  4. So that the beamed picture can be seen the right way up on the wall, you have to turn the screen display of your smartphone upside down. You can read how to do this with your smartphone in the operating instructions.

Adjustment: This is how the picture becomes sharp

1: So that the picture is really sharp, you have to try out the matching ones distances Determine from smartphone to lens (the object distance) and from lens to screen (the image distance).

2: Basically, the closer the smartphone to the lens is, the greater the distance between the lens and the sharp image. And vice versa: the further the smartphone is away from the lens, the smaller the distance between the lens and the sharp image.

3: There is a suitable image distance for every object distance - just try out different distances until you have the sharpest possible image. In other words: you push your smartphone back and forth in the box - and / or move the whole box back and forth in front of the screen. This is the best way to get a feel for the focus.

Explanation: This is how the projector works

And how does a picture that is shown upside down get the right way up on the wall? Quite simply: if the Rays of light go through the lens from the smartphone image, they are flipped over. So if the picture is upside down on the smartphone, you can see it on the wall the right way round.

You can imagine the whole thing like this: