Optical Illusions

Boyd, Edgar F.L.Gillespie

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.
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