Download Microscopes, Telescopes and Cameras: How Do They Work? Can

Microscopes, Telescopes and Cameras: How Do They Work?
Can We Build One?
Investigation 1: Creating a Microscope
Microscopes are used to produce enlarged images of objects that are too small to be studied in detail by
the unaided eye. In this investigation you will try to build a simple microscope using the optical bench
components from the previous lab involving lenses.
Minds On!
Look at the microscope on the counter and answer the following questions.
1) Describe how it works using the vocabulary learned in the unit thus far. Use diagrams to help explain
your answer.
2) What kinds of lenses are used in the microscope? How can this be proven?
3) How does the physical size of the microscope relate to the focal lengths of the lenses?
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
1
Action!
Microscopes have two lenses. The lens closest to the object is called the objective lens. The lens closest
to the eye is called the eyepiece lens, or ocular lens. The purpose of this investigation is to determine
how to arrange two lenses to create a simple compound microscope.
Question: How are the eyepiece and objective lens arrange to form a two-lens microscope? What is the
resulting magnification of the microscope?
Prediction
Based on the various lenses you have available, predict which arrangement of lenses will result in the
best microscope. Explain your answer.
Materials
Converging lenses of various focal length
Optics bench
Small letter or symbol to use for magnifying
Procedure
1. Determine the focal lengths of two or three different lenses.
2. Determine how the magnification of a distant object depends on the focal length of the lens
(Hold the lens about 30 cm from your eye).
3. Determine how the magnification of an object near a lens depends on the focal length of the
lens (Hold the lens about 30 cm from your eye).
4. Use the optics kit to build a microscope consisting of two lenses. The image should be larger and
inverted than the object if the system is acting like a microscope.
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
2
5. Once you have found the configuration the creates the largest and clearest image, draw a
diagram of your setup below, with all the appropriate image distances, focal lengths, and
distance between the lenses.
Analysis
1. Using only the objective lens, determine its magnification by measuring the image distance and
object distance from the lens.
2. Use the diagram of your microscope to determine thefore the eyepiece to find the magnification
of the eyepiece. Use an online simulator like to help you if you are having difficulty.
3.
Use these values to find the total magnification of your microscope.
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
3
Consolidate
How is a microscope similar to a telescope? Could you create a telescope with the same equipment?
Explain why or why not. Use a diagram to aid your explanation. Test your claim using the equipment.
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
4
Investigation 2: Dissecting a Camera
Modern digital cameras contain numerous mechanical, electrical and optical components that work
together to create the vivid, colourful, sharp pictures that fill our computer and smart phone screens
each day. Even the simplest disposable camera contains many systems that work together.
Minds On!
What kinds of lenses would you expect to find in a camera? Converging or Diverging? Explain your
answer.
Action!
Purpose
The purpose of this investigation is to determine how all of the components of a disposable camera
work together to create an image.
Materials
Disposable camera
Container to place individual parts
Safety goggles
Optics Bench
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
5
Procedure
1. Check for the batter and remove it if it is still present.
2. While wearing goggles, remove as many parts as possible.
3. Remove all the plastic lenses from the camera.
Observations
1. Sketch and identify each type of lens. Describe the location of each lens via a labelled diagram.
2. Identify as many parts as possible as mechanical, optical, or electrical in the chart below.
Mechanical
Optical
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
Electrical
6
3. Identify the converging and diverging lenses. Determine the focal length that focuses light into
the film. How does it relate to the overall size of the camera?
Consolidate!
Research and formulate questions about the role of each electronic component of the digital camera.
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
7
Investigation 3: Hello Jell-O!
Using the refraction lab and equipment from your text, design a lab that answers the following
questions.
What is the index of refraction of Jell-O?
What to Do
1.
2.
3.
4.
Determine the materials required
Write out your procedure
Graph and analyse your data
Write out your conclusions.
STAO 2011 – Lights, Camera, and Action! – Grade 10 Optics Unit (SNC2D & SNC2P)
Session #1220
Presenter: Dan Bruni
www.facebook.com/nelsonschoolsciencek12
8