THE SIGNS

Used in the Exploratorium

 
The Main Page
The Research
The Instructions
The Signs
The Pictures
The Warnings
The Biboliography

 

 

 

Text Box: What do you see? In front of you there should be three real objects:  a golf ball, a rabbi, and a castle.  Next to those objects you should see six things, called holograms.

 

Text Box: What to do? Gently pick up one of the holograms (the film that looks like a sheet of glass).  Hold each hologram up to the light source, moving the hologram around at different angles, until an image forms.  Try to guess what object was used in the making of each hologram. Hint:  Some objects are repeated.

 

Text Box: How does it work? Making holograms is a very complex process.  They have to be made in a dark room, with only a green light source to light the entire room.  Next, the desired object is set up about 25 cm. away from a laser with a piece of black paper in front of it to act as a shutter.  The film is set up in front of the object, barely leaning against it.  When it is perfectly quiet, the shutter is raised, and the laser shines on the film for twenty seconds. The shutter is then put down, and the film is sent through a number of different washings of different chemicals.  After many days of drying, the holograms are ready for viewing.