UNIT
E
UNIT TASK
Building an Optical Device
Optical devices have had a great impact on our society
and on our knowledge and understanding of the physical
world. The invention of the compound microscope, for
example, opened up the entire field of microbiology
(Figure 1). The study of diseases, their causes, and how
to prevent them was made possible through the use of
the microscope. The telescope in the last two decades has
totally revolutionized our understanding of astronomy.
Modern telescopes provide incredibly detailed pictures
of the planets and moons in our solar system, comets,
exploding stars, Einstein rings, and other phenomena.
SKILLS MENU
Questioning
Hypothesizing
Predicting
Planning
Controlling Variables
Performing
Observing
Analyzing
Evaluating
Communicating
For this Unit Task you will design and build a
prototype of an optical device.
Purpose
To build one of these optical devices:
• a reflecting telescope
• a microscope
• a projector
• a device that enables people to see spaces
normally hidden from view (for example, the
back of one’s head, hidden corners of a store,
under or around furniture)
• a device of your own design (either for a serious
purpose or for entertainment)
Equipment and Materials
Figure 1 Microscopes are important tools for diagnosing diseases,
especially those caused by micro-organisms.
In addition to their use as tools for scientific
exploration, optical devices are often used for
entertainment. Movie projectors are used to play the
latest action movie or breathtaking documentary. Many
people enjoy photography as a leisure activity and use
cameras to record memories of trips (Figure 2).
Your optical device must use at least two components
from this list:
• plane mirror
• converging mirror
• diverging mirror
• prism
• converging lens
• diverging lens
• ray box
These components will be available from the teacher.
You may use more than two if your school’s supply of
equipment allows this.
Your device will also require some materials to
hold your optical components together. The school
may provide some of these materials (for example,
glue, cardboard, tape).
Figure 2 We use cameras so often that we barely think about the
technology involved.
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Unit E • Light and Geometric Optics
NEL
Procedure
SKILLS HANDBOOK
3.B., 7.A.
Your school may require that school materials stay on
school property. If this is the case, your teacher will
allow you time to construct, test, and modify your
device in the Science classroom or lab.
1. Select a device that you will construct.
2. Design your device. Your design should include
a neat, scale drawing.
3. Prepare a list of materials that you will need.
Have your teacher review this list.
4. Construct a prototype of your device.
5. Test your prototype to see how well it works.
6. Modify your prototype until it produces a result
that you are satisfied with. This final version of
the prototype will be your finished device.
Analyze and Evaluate
(a) How well does your device do what you want it
to do?
(b) What problems did you run into in construction?
(c) How did you solve these construction problems?
(d) Describe the image that your device produces
under these headings:
• magnification
• quality of image
• image characteristics
ASSESSMENT CHECKLIST
Your completed Performance Task will be
assessed according to these criteria:
Knowledge/Understanding
✔ Demonstrate a knowledge of geometric optics.
✔ Demonstrate a knowledge of the imaging properties of
optical components.
Thinking/Investigation
✔ Develop a plan for constructing the optical device.
✔ Incorporate safety principles.
✔ Incorporate environmental considerations.
✔ Perform the task in an organized manner.
✔ Analyze the results.
✔ Evaluate the design and modify it as necessary.
Communication
✔ Prepare an appropriate lab report addressing the finalized
design, the materials used, a scale diagram, and an
evaluation of the device’s effectiveness.
✔ Communicate clearly during your design demonstration.
✔ Demonstrate an understanding of ray diagrams and the
proper symbols of optical components.
Application
✔ Use two or more optical components together.
✔ Achieve the stated goal with the optical device.
✔ Build a mechanically sound, environmentally friendly, and
safe device.
✔ Pay attention to the overall appearance and aesthetics of
the device.
(e) How easy is your device to use?
(f) How would you do this activity differently if you
were to do it all over again?
Apply and Extend
SKILLS HANDBOOK
4.A., 4.B.
(g) Draw a neat ray diagram to illustrate how your
device produces an image.
(h) Demonstrate your device to your class.
(i) Research real-life examples of the device that you
designed.
GO TO NELSON SCIENCE
NEL
Unit E Task
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