How to do physical aperure imaging, the principle of aperture imaging

Experimental equipment: rectangular cardboard, candles, white paper, paper boxes, large sewing needles, iron clips, bottle caps.

2 Clamp both sides of the cardboard with iron clips so that the cardboard stands upright on the tabletop.

3 Attach the candle to the cap. Light the candle by placing the candle in front of the cardboard so that the center of the candle flame is at the same level as the small hole in the cardboard.

4 Stand the carton upright on the back of the cardboard, and then put a flat piece of white paper on the vertical surface of the carton, so that the center of the paper surface is on the same level as the small hole in the cardboard. Looking at the white paper, is there a candle flame on the white paper? (A handstand of a candle flame will appear on the white paper.)

5 What happens to the image of the candle flame on the white paper when you move it perpendicular to the cardboard surface? (When the white paper is closer to the cardboard, the image of the candle flame is smaller but brighter; When the white paper is farther away from the cardboard, the image of the candle flame is larger but darker).

6 Use a needle to pierce 2 more holes in the cardboard 2 cm away from the first hole, what happens to the image of the candle flame on the white paper? (If there are three holes in the cardboard, there will be three inverted candle flames on the white paper.) As shown in Figure 1-2).

Explanation of the phenomenon: The flame of a candle is made up of many small glowing dots, each of which emits light in all directions. When the light emitted by a luminous spot passes through a small hole in the cardboard, a spot of light forms on the white paper.

Each luminous point on the candle flame will form a corresponding light spot on the white paper, and all the light spots on the white paper will form a candle flame image. When there are multiple holes in the cardboard, the light from the candle flame will form an image through each hole, and multiple images will be seen.

1. The purpose of the experiment: to observe how light travels in the air through the phenomenon of small hole imaging. 2. Experimental Principle:

Because the light travels in a straight line in the air, the light of the candle can be reflected on the wall through a small hole in the cardboard to form a reflection like a candle's flame. 3. Experimental equipment: 1 candle, 2 matches, 3 cardboard, 4 pins, 4 pins, 4 Experimental steps:

First use a pin to drill a small hole in the cardboard, put it for later use, then use a match to light the candle, fix it at a place about 30cm away from the wall, place the cardboard between the candle and the wall, cover the light in the room, adjust the height of the candle, so that the flame of the candle is just aligned with the small hole in the cardboard, and slowly move the cardboard back and forth until you see a clear shadow on the wall (as shown below). Results: After experimenting, I found that the light of the candle on the wall is inverted, and when the candle is pointed against the cardboard, the farther the candle is from the cardboard, the smaller the shadow of the candle, and the closer to the cardboard, the larger the shadow of the candle.

So, it proves that light travels in a straight line in the air.

The principle of small hole imaging: the linear propagation of light

The principle of aperture imaging is: the linear propagation of light Analysis: Because light travels in a straight line in the same medium, the upper and lower parts of the light source are exchanged when the light passes through the aperture, but the imaging shape remains unchanged, and the image is the same as the shape of the light source.

Take a sharpened pencil and make a small hole in the center of a piece of cardboard.

The small hole is about three millimeters in diameter and manages to hold it upright on the table, and then the curtains are closed to dim the light in the room.

Light a candle and place it near the hole. Take a blank piece of paper and place it on the other side of the hole. This way, you will see an inverted candle flame on the white paper.

We call it the image of a candle. Move the white paper back and forth to see how the candle flame looks. When the white paper is closer to the candle, it is small and bright; As the white paper slowly moves away from the candle, it seems to slowly grow larger and darker.

Changing the size of the holes, let's look at the changes in the image of the candle.

You can prick several holes of different sizes and shapes on a piece of cardboard, with holes a few centimeters apart. At this time, on the white paper, there are several inverted images corresponding to the small holes. They are all the same size, but the degree of clarity varies, and the larger the hole, the less clear the likeness.

As long as the hole is small enough, its shape, whether it is square, round, or oblate, has no effect on the clarity of the image and the shape of the image.

Experimental research. 1.Put candles, perforated screens, and grounded glass screens.

Light the candle and adjust the height of the candle and the screen so that the center of the candle's flame, holes, and ground glass screen are roughly in a straight line. The distance between the candle and the small hole screen should not be too large. After the adjustment, you can see the actual image of the candle flame upside down on the frosted glass screen.

2.By moving the position of the candle or frosted glass screen, you can see that the closer the candle is to the hole or the farther away from the ground glass screen is from the hole, the larger the image will be.

Conclusions of the experiment. Light travels in a straight line in the same homogeneous substance.

When the image distance is constant, the closer the object distance, the larger the image and the brighter it becomes. The farther away the object is, the smaller the image becomes and the brighter it dimens.

When the object distance remains the same, the screen near image becomes smaller and brighter; The screen teleimage becomes larger and darker.

When the position of the object, hole and screen remains unchanged, imaging is the premise, and the image becomes brighter when the hole is relatively large.

Principle: Light travels in a straight line in the same homogeneous medium without being disturbed by gravity.

The sun gives human beings light and heat, which is an indispensable source of light for human beings. But due to the rotation of the earth, day and night are formed. Every night, darkness covers the land.

The ancestors of mankind, who lived in ancient times, were powerless against the night. Darkness gives people a terrible, hateful feeling. I don't know how many centuries it took for mankind to discover that fire can also provide light and heat.

At first, natural fire was used, and later artificial friction was invented to make fire. The invention of artificial friction for fire was an epochal advance in human history, which "for the first time enabled man to dominate a force of nature, thereby finally separating man from the animal kingdom". Peking Man who lived 500,000 years ago already knew how to use natural fire, and about tens of thousands of years ago, humans learned to use the method of drilling wood to make fire artificially.

Fire has been the only artificial light source that people can use for a long time, and later people created oil lamps and candles, or inseparable, until the invention of modern light sources replaced fire.

The principle is:Light travels in a straight line in the same homogeneous medium without being disturbed by gravity.

About 24,500 years ago, a Chinese scholar Mo Zhai (Mozi) and his students conducted the world's first experiment on the inverted image of a small hole, explaining the reason for the inverted image of a small hole and pointing out the nature of the straight line progression of light.

This is the first scientific explanation of the linear propagation of light. If a plate with a small hole is used to block between the wall and the object, the reflection of the object will be formed on the wall, and we call this phenomenon the image of the hole.

When the middle plate is moved back and forth, the size of the image on the wall also changes, which illustrates the nature of light propagation in a straight line.

Use a plate with a small bai hole to block between the screen and the object, and the dao image of the object will be formed on the screen, we.

This appearance is called aperture imaging. Move the middle plate back and forth, and the size of the image will also change. This phenomenon reflects the nature of light propagating in a straight line.

Also, only small holes, not large holes, why? Take a look below:

Aperture imaging means that each ray of light can only be projected on a point of the light screen through the aperture, so it can present a clear real image. If the hole is large, a little light source will be scattered on the light screen, and the image obtained will not be clear, rather than not presentable.

Steps:1. Use scissors to cut off one end of the opening of the can.

3. Use an awl to make a small hole in the bottom of the can.

4. Tie a small hole (diameter less than mm).

5. Roll it into a paper tube with hard cardboard just enough to insert it into the can.

6. Fix with transparent glue.

7. Finished paper tubes.

8. Seal the cooking paper with a rubber band at one end of the paper tube.

9. Put the paper tube in the cut can.

10. Aim the small hole at the bright scene, and you can see the upside-down image on the screen (cooking paper).

Experiment Description: <>

Since the light travels in a straight line, the light from above the scene hits the bottom of the screen through the hole, and the light from below comes to the top of the screen through the hole, so we see an upside-down image on the screen.

Safety measures: 1. This experiment uses scissors and a cone to be carried out under the guidance of an adult.

2. The cut edge of the can is very sharp, so be careful, it is best to stick a circle of transparent rubber strip on the cut mouth of the can.

Make small hole imaging with a paper cup:

1. Prepare a paper cup and cover the opening side with white paper.

2. Poke a small hole with a needle at the bottom of the paper cup.

3. Light a candle and finish serving.

4. Put the hole in the cup close to the burning candle and the image on the white paper.

5. Put the perforated side of the cup a little closer to the candle, and the candle will become larger.

Conclusion: Light propagates in a straight line in the same homogeneous substance. The closer the object is, the larger the image and the darker the brightness; The farther away the object is, the smaller and brighter the image.

Aperture imaging is an optical imaging method, which is a method of observing objects by using the real or virtual image formed by light after passing through a small hole. When light passes through a small hole, the light will form an inverted real or virtual image due to the straight-line propagation nature of the light. The principle of Konobo Jingchi imaging is as follows:

When the light passes through a small hole, the light will form an inverted real or virtual image due to the liturgical propagation of the light in a straight line.

The principle of small hole imaging is actually the linear propagation of light, which is wide and bright. Use a plate with small holes to block between the screen and the object, and an inverted image of the object will be formed on the screen, which we call this phenomenon small hole imaging. Changkuan.