Optical Instruments and Lenses
Name: _______________________________________
Date: _______________
Period: ____
Page 443 - 449
Directions: Write the name of the name of each optical instrument that matches each description. Your choices
can be telescope, microscope, or camera. More than one instrument can match each description.
1. has two lenses called the eyepiece lens and objective lens: ________________________________________
2. allows a person to see faraway objects more clearly: _____________________________________________
3. can be made with a mirror instead of a lens in order to collect more light: ____________________________
4. moves a lens to focus an image sharply on a piece of film or a digital sensor: _________________________
5. collects more light than a human eye can to create a useful image: __________________________________
6. uses a combination of lenses and a tube to enlarge objects: ________________________________________
7. allows a person to see small objects more clearly: _______________________________________________
Directions: Complete each sentence below with terms from the lesson.
1. A (n) _________________________ is a curved, transparent object used to refract light.
2. Every lens has at least one ________________________ surface.
3. A lens that bulges outward is called a ______________________________
4. A (n) ________________________ lens always forms and image that is on the same side of the lens as the
original object and right-side up.
5. A convex lens has a least one side that __________________________.
6. A convex lens causes light rays to _____________________________
7. All the light rays that pass through a convex lens come together to one _______________________
8. The ______________________ of a convex lens is the point on the major axis of the lens at which all beams
of light traveling through and away from the lens converge.
9. The distance between the center of a lens and its focal point is the ___________________________ of the
lens.
10. The image of an object formed by a convex lens depends on the position of the object in relation to the
_______________________ of the lens.
11. Light travels more ________________________ in a lens than it does in air.
12. A Camera is focused by changing the distance between the camera’s ________________________ and its
film so that the film is the exact location where the image is formed.
13. An optical _______________________ is an optical instrument that uses two convex lenses to allow you to
see small objects.
14. Refracting telescopes use two __________________________ lenses.
15. A _________________________ is an optical instrument that makes objects that are far away look closer.
16. A refracting telescope uses two convex lenses, called the eyepiece and objective lenses, at either end of a
_______________________ to enlarge the image of distant objects.
17. __________________________ telescopes are sometimes used to see distant to faint objects because it is
easier to make and support large mirrors than it is to make and support large lenses.
18. Because it is easier to collect a large amount of light with a mirror than a lens, most large telescopes used to
view faint and distant objects use ________________________ to collect light and are called reflecting
telescopes.
19. Lenses make use of refraction to form ___________________________.
20. Lenses can be used to collect and focus _________________________ from objects that wouldn’t
otherwise be visible.
Directions: Read the story about the Hubble Space Telescope and answer the questions.
Hubble Space Telescope
In many places on Earthy you can look up into the night sky and see stars, if you live in a city, the lights
can prevent you from seeing many of the more distant or dim objects in the night sky-even with a telescope.
If you were to go out into the desert, where the air is clear and there are few lights nearby, you would
see many, many more stars in the sky. However, your vision would still not be as good as it could be. Just as
clouds scatter light and appear to be white because they are made up of small pieces of dust and small droplets
of water, other, more spread-out particles in the air can also scatter light. This scattering can make it harder for
us to see objects that are far away. Also, because light travels at different speeds through the air, the light
coming into our atmosphere can bend slightly. This bending makes it more difficult to see objects that are far
ways.
To solve this problem, scientist and engineers from NASA and European Space Agency worked
together to build the Bubble Space Telescope that orbits Earth by satellite. Because it is outside Earth’s
atmosphere, it can capture images of far away object without the troubles caused by lights on Earth or by
particles in the atmosphere. Once it captures the images they are sent by radio waves o computerized
monitoring stations on Earth where scientist can collect and analyze the images. The Hubble Space Telescope
has provided amazing images of the activity of stars and other heavenly bodies from our solar system and far,
far beyond. These images help us to understand things that happened millions of light-years away and millions
of years ago.
1. Why would be better to look through a telescope from the top of empty, high, ad dry mountain, then it would
be to look from a city at sea level? _____________________________________________________________
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2. Is the Hubble Space telescope a refracting or reflecting telescope? How do you know? _________________
_________________________________________________________________________________________
3. Because the Hubble Space Telescope can capture images from objects many light-years away, it helps us to
understand things that happened many years ago, Why is this true? ____________________________________
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