"Lens in Life" Lens and its Application PPT Courseware 8

Description

"Lens in Life" Lens and its Application PPT Courseware 8

learning target

1. Know the imaging characteristics of cameras, projectors (slide projectors) and magnifying glasses.

2. Understand the main characteristics of real and virtual images of objects.

self-study

1. What are the main parts of a camera? What is its lens equivalent? What is the equivalent of film? What are the characteristics of the images of objects on film?

2． What are the main parts of a projector? What is its lens equivalent? What is the screen equivalent to? What is the function of a plane mirror? What are the characteristics of the image formed by the projection film on the screen?

3. What is the essence of a magnifying glass? What are the characteristics of the resulting image?

4. What causes real and virtual images? How to distinguish between a real image and a virtual image formed by an object?

Discussion and exchange

camera

1. What are the main parts of a camera?

The principle of camera

1. The lens of the camera is equivalent to a convex lens, and the film is equivalent to the screen.

2. Characteristics of camera imaging: inverted, reduced real image

Cameras in life----digital cameras

Digital cameras use image sensors instead of film to convert light signals into electrical signals, and then into digital signals, which are stored in the camera's memory.

Tracking exercises

【1】After taking a bust portrait, someone wants to use the same camera to take a full-length portrait. At this time, should he be farther away from the camera or closer? At the same time, adjust the focus ring to move the film away from the lens or closer to the lens?

[Analysis] When taking a bust portrait instead of a full body portrait, the image actually shrinks. At this time, the image distance should be reduced and the object distance should be increased at the same time.

[Answer] People should stay away from the camera while keeping the film close to the lens.

【2】Classmate Xiaochen was taking a group photo of the whole class in front of the school gate. He found that the two students on both sides couldn’t take the photo. Please help him solve this problem.

[Analysis] If the images of two classmates are put into the film, the images of the whole class will be shrunk.

When imaging with a convex lens, the object distance increases, the image distance becomes smaller, and the image becomes smaller. As long as Xiaochen moves back a little to increase the object distance, and at the same time shortens the distance between the lens and the film to reduce the image distance, he can take in the entire class.

[Answer] Please Xiaochen step back a little and shorten the distance between the lens and the film, so that the whole class can be photographed.

Discussion and exchange

projector

1. What are the main parts of a projector?

The principle of projector

The projector lens is equivalent to a convex lens, and the screen is equivalent to a light screen

Projector imaging features: inverted, enlarged real image

Projector use

1. What is the role of a plane mirror here?

Change the propagation path of light so that the image of the projection film appears on the screen in front of the projector

2. How should we display the slideshow if we want to see it standing upright on the screen?

The slideshow needs to be played backwards

Compliance testing

1. Which of the following is not an application of lenses in daily life:

A.Camera B.Magnifying glass C.Projector D.Periscope

2. The objects that can be enlarged into real images through the following optical devices are:

A.Camera B.Projector C.Magnifying glass D.Plane mirror

3. The "ginseng wine" currently sold on the market contains a ginseng soaked in a wine bottle. The ginseng you see should be:

A. The real thing of ginseng B. The same size image

C. Enlarged virtual image D. Reduced real image

The lens of an ordinary camera is equivalent to a _______ lens. The focal length of an ordinary camera lens is 40cm. When the distance between the person being photographed and the lens is greater than ________cm, an inverted and reduced _______ image will be obtained on the film ( Optional: real or virtual).

Memorize the applications of convex lenses

① When μ＞2f, camera and eyes;

②. When f＜μ＜2f, slide projector and projector;

③ When f>μ, magnifying glass;

④. The microscope is magnified twice and is a combination of optical tools.

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For more information about the PPT courseware "Lens and its Applications in Life" PPT courseware, please click on the "Lens and Its Applications in Life" PPT courseware.

"Lens in Life" Common Optical Instruments PPT Courseware 3:

"Lens in Life" Common Optical Instruments PPT Courseware 3 Self-Study Materials 1. What are the main parts of a camera? What is its lens equivalent? What is the equivalent of film? What are the characteristics of the images of objects on film? 2． What are the main parts of a projector?

"Lens in Life" Common Optical Instruments PPT Courseware 2:

"Lens in Life" Common Optical Instruments PPT Courseware 2 Make some equipment: two paper tubes, convex lenses, and translucent paper. Take a look. Please pick up the camera you made and face it outside the bright window. Pull the paper tube to change the lens and semi-transparent paper. What do you see between the transparent sheets? ..

"Lens in Life" common optical instruments PPT courseware:

"Lens in Life" Common Optical Instruments PPT Courseware 1. Slide Projector and Transparency Film The pattern forms an enlarged and inverted real image through a convex lens. 2. Camera The image and object are on both sides of the lens, and the camera can form an inverted, reduced real image. 3. Telescope...

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Update Time: 2024-10-22

This template belongs to Physics courseware Lu Jiao edition eighth grade physics volume 1 industry PPT template

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