Optical Illusions

Boyd, Edgar                  F.L.Gillespie
510 Barrington Ct.           468-7263
University Park, Il 60466
534-6486

Objectives:

Given the introduction to optical illusions ,each student will be able 
to identify and construct four optical illusions illustrated in class. 

Apparatus needed:

   1.White cord string (medium)
   2.Transparent sheets (4) 8"x10"
   3.Overhead projector
   4.Ultra violet light
   5.Electric drill
   6.3 cardboard circles 12"in diameter
   7.Assorted fluorescent paint
   8.Felt pens designed to write on transparent sheets
   9.Scissors
  10.Straight edge (ruler) 
  11.Two 8"x 12" cards 
  12.Six (6) 3" screws; threaded with washers and bolts

Recommended strategy:

Optical illusions are deceptions of the mind.  Sometimes these 
illusions are concerned with color, and sometimes with objects that are 
moving. 

       Constructing Optical Illusions Using Light.
Divide each of the three cardboard circles into four equal parts.  
Shade each of the sections on each cardboard with different colors 
using a different color fluorescent paint.  Place small hole in center 
of each cardboard.  Place 3" threaded screw through washer, place screw 
with washer through painted side of cardboard.  Place washer on back of 
the cardboard and lock with bolt.  Attach completed assembly to drill 
and lock in place.  Stand in front of ultra violet light, turn off 
lights in room.  Turn on drill and observe color patterns.  Repeat 
above procedures for each of the remaining circle cardboards.
    CAUTION: DO NOT LOOK DIRECTLY INTO THE ULTRA VIOLET LIGHT
     
      Optical Illusions With Color        
Take four(4) 12" sections of string and place each in a different color 
of fluorescent paint.  Allow string to dry.  Construct on the 12" x 24" 
cardboard using straight pins.  Using the examples in the packet or 
examples given in chapter 6, construct several optical illusions of 
your choice . 

      Optical Illusions With Changeable Figures
Place several figures on the board taken from the packet of information 
or chapter 6 of reference book.  Each student will duplicate each 
figure on the 8"x12" card.  One can not duplicate with any degree of 
accuracy the optical illusions that will illustrate changeable figures 
on a computer.  To obtain the optical illusions that will illustrate 
changeable figures, please contact Edgar Boyd at the school listed on 
this Mini-Teach Summary. 

Referemce: 

Beeler, Nelson F. and Branley, Franklyn M. Experiments in Optical
    Illusions, New York: Thomas Y. Crowell Co., 1951.