Science,English,and math 8th

【There’re lots of mysterious things around us】

《Why can Japan make jeans spread over the world?》

Jeans were washed in industrial washing machine with pumice 軽石. The color on jeans was lost on purpose for fashionable style. In addition, the way of chemical wash has been announced in 1986. Chemical reaction on chlorinated chemicals makes the color on the jeans lose in part on purpose, so the jeans becomes a fashionable item which are loved by youths all over the world.

But there used to be crisis on indigo which dyes the denim. Indigo is the one which natural dye is combined artificially.

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【There’re lots of mysterious things around us】

《Why Japan can make jeans spread all over the world?》

Other material which was evolved as dyes for cotton has been invented. Then the demand for indigo decreased and was about to disappear in 1950s, but there has been demand for seventeen thousand ton every year at present.

《We don’t need any iron for it. There is no wrinkle in a shape memory 記憶形状 shirt. Why?》

There is a place where molecules on long and narrow cellulose fiber is stuffed and the other where molecules are comparatively sparse in the thread of cotton shirt. After washing it…

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【There’re lots of mysterious things around us】

《We don’t need any iron for it. There is no wrinkle in shape memory shirt. Why?》

After washing, molecules in the water crawls into, and makes molecules on cellulose which is entangled each other loosen, so it seems there is no wrinkle for a while, but the wrinkle appears again when drying.

If connecting the molecules on cellulose which is the sparse part with a chemical combination, it is hard to be bend. Then formaldehyde of which molecules are small is used for it. If applying steam of formaldehyde, the molecules on cellulose are connected.

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【There’re lots of mysterious things around us】

《We don’t need any iron for it. There is no wrinkle in shape memory shirt. Why?》

The molecules on the cellulose is united firmly as if a bridge were build among the molecules on the cellulose. Even if the shirt is wrinkled, washing makes its shape return to its original form. When washing it repeatedly, its form is all right.

《If having clung to a shirt, it’s a serious matter. Why is a lipstick hard to remove?》

Why is the lipstick hard to get rid of? How do we remove it? The one which make the lipstick develop its color is molecules on pigment

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【There’re lots of mysterious things around us.】

《If having clung to a shirt, it’s a serious matter. Why is a lipstick hard to remove?》

If adding material which grasps the lipstick firmly and makes the lipstick blend well, its pigment is hard to get rid of. It works on account of special high molecules.

The component on the lipstick isn’t only pigment, high molecules, but oil which has volatility 揮発性, the component which makes the lipstick moisturize, and moisturizer.

When putting on the lipstick, its oil volatiles and starts to jump out of the lipstick. Then the high molecules hold hand…

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【There’re lots of mysterious things around us】

《If having clung to a shirt, it’s a serious matter. Why is a lipstick hard to remove?》

Then high molecules hold hand in hand and make meshes and tangle the molecules of the pigment with the meshes. After that the moistures exude from the mesh, so the mesh is covered with the moistures, so its color becomes harder to remove.

If the lipstick is clung to the clothes, it is removed by mixture of neutral detergent in the kitchen and cleansing cream.

There are various pigments like chlorophyll which is green in plants, or like hemoglobin which is …

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【There’re lots of mysterious things around us】

…or like hemoglobin which is red in the blood.

《Even if it’s a hard food, it is cut clearly. Why does a kitchen knife cut?》

Almost all of kitchen knives which we see in a supermarket at present are made up with stainless or ceramics, but Japanese kitchen knives like vegetable knife and 出刃包丁 is made up with iron, but the iron is alloy.

If trying to make the kitchen knife with pure iron of which element symbol is Fe alone, it’s very hard, and even if it is made, it is too soft to use as blade, so in general, except for pure material on iron …

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【There’re lots of mysterious things around us】

《Even if it’s a hard food, it is cut cleanly. Why can a kitchen knife cut?》

…except for pure material for iron, the iron has various chemical elements, especially the most important one for the nature on the iron is carbon. The iron is called 純鉄, 鋼, or 銑鉄, according to the content on the carbon.

As to the content on the carbon, 純鉄 and 鋼 is from 0.03 to 1.7 %, and the 銑鉄 is more than 1.7%. We call the 純鉄 and 鋼 steel as general term.

The more the amount of carbon is, the stronger the iron is but the the more fragile.

On the other hand, the…

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【There’re lots of mysterious things around us】

《Even if it’s a hard food, it is cut cleanly. Why can a kitchen knife cut?》

On the other hand, the less the carbon is, the softer and more flexible.

The hard 鋼 and soft and flexible iron is piled up and is burned with fire and is hit repeatedly, and two kind of materials are extended and the Japanese kitchen knife is made so as to make the two different natures be compatible.

In its process, adopting the way of 焼入れ and 焼き直し, the iron is forged and its nature becomes strong. Crystal which is a placement on atom is changed on the iron…

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【There are lots of mysterious things around us】

《Even if a hard food, it is cut cleanly. Why can a kitchen knife cut?》

Crystal which is a placement on atom of the iron is changed in varied ways, according to the temperature.

As to 鋼 which has lots of molecules on the carbon, when its temperature rises up, the molecules on the carbon go into between molecules on the iron neatly. If cooling it slowly, it returns to the original situation, but after rising its temperature and cooling it with water or oil rapidly, it can’t return to its original situation. The situation of rising the…

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【There’re lots of mysterious things around us】

《Even if it’s a tough food, it is cut cleanly. Why can a kitchen knife cut?》

The situation of rising the temperature is fixed as it is. The iron envelopes the molecules on the carbon, and becomes a hard steel. It’s the situation in which 焼き入れ is done.

When heating the steel which the 焼入れ was done and its temperature becomes from 400 to 600 degree, the placement on the iron and carbon changes again. If cooling it slowly, it becomes the steel which is supple しなやか and flexible. It’s 焼き直し.

By the way, speaking of ceramics, pottery alone occurs…

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【There’re lots of mysterious things around us】

…speaking of ceramics, pottery alone occurred to me, but except for the pottery, it is used for the kitchen knife as well. I’ve never heard of it until now.

《Even if a fish bumps into it, it’s all right. Then a gigantic water tank isn’t broken in aquarium. Why?》　

What kind of material is used for a tremendous water tank in aquarium ?,and how is it made? For instance, a huge water tank at ちゅら海 aquarium in Okinawa prefecture, its height is 8.2 meters, the width is 22.5 meters, and the thickness is 60 centimeters. Each of them is a single panel…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the gigantic water tank in aquarium isn’t broken. Why?》

Each of panels which is used for the huge water tank is a single panel without having any column, and is the biggest in the world as panel for the water tank

It has been often thought it is made up with glass, but it isn’t. It’s acrylic which is kind of plastic and in fact is made from petroleum. If it’s made by glass, it can’t resist the pressure of the water which reaches 7500 ton in the water tank, and it’s not so transparent like that

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the the huge water tank in aquarium isn’t broken. Why?》

While the specific gravity 比重 on the acrylic resin is twice as light as the glass, but its strength is 15 times as strong as the glass, and its workability is high. When making something, its process is easy, then we say its workability is high.

What is the specific gravitation? For example, there is some material, and there is some water of which cubic volume is same as the material. How many times is the material as heavy as the water?

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the tremendous water tank in aquarium isn’t broken. Why?》

Its numerical value is the specific value. For instance, preparing for some water of which volume is same as my naked body, and measuring each of weight. If my weight is 48 kilogram, and the water is 50 kilogram, my specific gravity is 48 ÷ 50= 0.96.

Except for the panel at the water tank in aquarium, the acrylic resin is used for in varied ways like windshield on airplane, a display on store, building materials, furniture, home …

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the huge water tank in aquarium isn’t broken. Why?》

…the acrylic resin is used for in varied ways like windshield for airplane, a display on store, building material, a piece of furniture, an electric appliance, artist’s paint, and medical materials like contact lens, and denture 義歯.

But making a thick panel with the acrylic resin isn’t easy. How is the acrylic panel in the water tank made?

Several acrylic plates of which thickness are below 4 centimeters are stacked, thus the acrylic…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the huge water tank in aquarium isn’t broken. Why?》

Thus, the acrylic plate for the water tank in aquarium is made, but each of the acrylic plate isn’t clung to by glue simply. If being the glue of which reflective index 屈折率 is different from the acrylic plate, it reflects the light, and if stacking them by dozens, the acrylic plate loses it transparency, so we can’t see anything in the opposite direction through the acrylic plate.

First of all, flowing acrylic which is liquid between the…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the tremendous water tank in aquarium isn’t broken. Why?》

First of all, flowing acrylic which is liquid between the two acrylic plates. When the temperature on acrylic becomes 82 ℃, it start transforming, so heating the acrylic immediate before 82 degree centigrade, and causes a chemical reaction, polymerization 重合.

What is the polymerization?

At first, there is a chemical compound which is highly polymerized compound高分子化合物. The highly polymerized compound is the one of which amount of…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the gigantic water tank in aquarium isn’t broken. Why?》

The highly polymerized compound is the one of which amount of molecule is over ten thousand. The highly polymerized compound is the one which the chemical compound of low molecular weight 低分子量 connects a lot. The low molecular weight which connects a lot is called monomer 単量体.

The monomer is raw material for the high polymerized compound, so the highly polymerized compound is made up with the monomer. Lots of monomer is connected, and…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the tremendous water tank in aquarium isn’t broken. Why?》

…and its process is polymerization 重合.

When the polymerization is done well, two of the acrylic plates unite with the level of molecule, and they integrate. It is done by stacking of dozens of acrylic plates, and the panel for the water tank of which thickness is 60 centimeters is completed.

When the glass become thick, its color becomes greenish, on the other hand, when the acrylic becomes thick, it remains transparent. Its process…

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【There’re lots of mysterious things around us】

《Even if a fish bumps into it, it’s all right. Then the huge water tank isn’t broken. Why?》

Its process is able to be done with comparatively in low temperature.

As to acrylic painting is acrylic resin is used for its adhesive bond. It’s water soluble 水溶性. It becomes dry quickly, and after being dry, it becomes water resistant.

《Its landscape looks clear from the window. Why is the plate glass transparent?》

The plate glass for a window is transparent. Why? It’s mysterious.

First of all, all of materials is made up with atoms, when it’s…

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【There’re lots of mysterious things around us】

《Its landscape looks clear from the window. Why is the plate glass transparent?》

…when it’s not solid but liquid which is melted, the way of arranging on the atom is scattered, but when being cool and becoming solid, atoms are arranged regularly, and its crystal is made like that, but all of the materials aren’t like that.

When being cool and solid, all of the materials are arranged regularly, but some of them spread loose. For example, oxide 酸化物 , and oxide salt 酸化物塩. Some of them are become hard without forming crystal. The glass is one ...

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【There’re lots of mysterious things around us】

《Its landscape looks clear from the window. Why is the plate glass transparent?》

The glass is one of them.

When the light comes from the outside through the glass, there is the one which catches the light and prevents the light from coming through the glass like iron, for its atom is arranged so neatly and regularly that its crystal is made. Its power of maintaining is so strong that the light can’t come through.

On the other hand, as to the glass which doesn’t block the light but the light comes through, its atom doesn’t form...

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【There’re lots of mysterious things around us】

《Its landscape looks clear from the window. Why is the plate glass transparent?》

…its atom doesn’t form the crystal, so the light which comes from the outside isn’t prevented, the light comes through as it does, so the plate glass looks transparent.

As to the discovery on the glass by the humankind is some five thousand years ago from now on in Mesopotamia. Some people made a bonfire 焚き火 at the beach of the lake in Mesopotamia. Then something like water began to flow, and even after the fire burned out, something like water was left. What’s it?

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【There’re lots of mysterious things around us】

《Its landscape looks clear from the window. Why is the plate glass transparent?》

Then sodium carbonate 炭酸ナトリウム which was included in the water of the lake and 硅砂 in the sand were melted with the heat of the fire and were mixed each other. It seems to be the origin on the glass.

Moreover, the technical skill of blowing glass has made the glass make more easily and lots of glass was made, and it was put into practice some two thousand years ago from now on.

But the flat complete plate glass learns to be made recently, in the middle of the 20…

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【There’re lots of mysterious things around us】

It’s in the middle of the 20th century when the flat plate glass learns to be completed.

《It’s used for softener 柔軟剤 for washing clothes. Why does aromatic smell pleasantly?》

There is the one which the aromatic and deodorant 消臭剤 become the one, but without being removed by the deodorant, the aromatic smell pleasantly. It’s mysterious.

The author said he was going to look at the mechanism from the side of the deodorant, but it’s not the deodorant which sprinkles lots of fragrance in the air and covers the bad smell with the fragrance.

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【There’re lots of mysterious things around us】

《It’s used for softener of washing clothes. Why does aromatic smell pleasantly?》

The deodorant which decreases the molecules on stink itself in the air has two types. The one is making the molecules on stink cling to like activated carbon 活性炭, mineral of zeolites, or material which has lots of holes. The deodorant which is in a fridge is that one, but then why doesn’t the deodorant absorb the fragrance as well? Then we make use of difference on nature of molecules.

Molecules on stink have lots of atom of nitrogen, and the one of sulfur 硫黄.

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【There’re lots of mysterious things around us】

《It’s used for softener of washing clothes. Why does aromatic smell pleasantly?》

The molecules on stink cling to the activated carbon easily.

On the other hand, the molecules on fragrance have lots of hydrocarbon which resembles element on petroleum like the one which is included in tangerine peel, or other which trees give off in the forest. The activated carbon can’t absorb them easily.

The other type is chemical reaction prevents the stink from returning to the air. The one with which is reacted chemically is varied. For example acid and…

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【There’re lots of mysterious things around us】

《It’s used for softener on washing clothes. Why does aromatic smell pleasantly?》

For example, acid and alkaline are neutralized, chemical reaction between metal ion and suffer compounds, or oxidation reduction 酸化還元.

For instance, lots of stink which is caused in restroom has atom on sulfur. When the atom on sulfur reacts with ion of iron, copper and zinc 亜鉛, it becomes stable sulfide 硫化物. Or when reacting with chlorinated material 塩素系, it oxides, and changes into material which doesn’t have any stink.

On the other hand, molecules on…

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【There’re lots of mysterious things around us】

《It’s used for softener for washing clothes. Why does aromatic smell pleasantly?》
　
On the other hand, the material which gives off the fragrance seldom reacts chemically like that. As a result, without removing fragrance, removing stink alone, fragrance drifts in the air.

While the stink is a kind of sign which makes us inform that something is dangerous like rotten smell, fragrance makes us feel comfortable.

Ancestor of mammal becomes nocturnal so as to escape from dinosaurs. Instead of sense of visual, it developed the sense of smell.

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【There’re lots of mysterious things around us】

《It is chilled well and looks tasty. Why does water drops cling to a glass?》

When leaving water with the ice in glass alone, water drops cling to the outside of the glass, for steam which moves around the glass is cooled by the outside of the glass, and condenses, and changing into liquid of water.

The surface on the glass looks smooth at a glance, but there is delicate unevenness there, and the delicate unevenness is a suitable place that the steam changes into the liquid.

When watching the glass in the water with ice, we can observe the…

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【There’re lots of mysterious things around us】

《It is chilled well and looks tasty. Why does water drop cling to a glass?》

…we can observe the moment when the water drop is caused on the surface of the glass. Its start is a phenomenon which the air sways around the glass, for the temperature drops in the air, and refractive index 屈折率 changes, so the air sways.

In the next, sitting down in the direction where the light comes through, and watching how the air sways. We could have watched the steam changes into water drops on the surface of the glass, the author said like that, but …

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【There’re lots of mysterious things around us】

…but I’m afraid I can’t wait for a long time patiently until the steam changes into the water drops if being thirsty.

I’m going to express chemistry on technology from now on.

【We can understand the mechanism on technology and electric appliance】

《We can enjoy ourselves in the three dimensional at home at present. Why does the three dimensional look as if it popped out from the screen?》

The eyes of human can catch an image in three dimensional way, for there is parallax 視差 between the eyes of both of left and right. When putting something…

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【We can understand chemistry on technology and electric appliance】

《Why does the three dimensional look as if it popped out of the screen?》

When putting something at the center of left and right eyes and looking at it with one eye closed alternately, the position on something looks different. We call it binocular parallax, and the parallax makes the brain in the human makes us feel depth and cubic effect.

Making use of the binocular parallax for a movie, and it makes us feel the screen on the movie three dimensional, though it’s plane actually. Then glasses of 3D is indispensable.

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【We can understand chemistry on technology and electric appliance】

《Why does three dimensional look as if it popped out from the screen?》

Each of different film is stuck to left and right for the lens in the three dimensional glasses, and the glass sends an image which has the different position to both of the eyes each other, so we can see the three dimensional image.

Each way of color filter, polarization 偏光, and what is called a shutter has been adopted at present.

As to the color filter, there is three wave length which we can see with our naked eyes, red, green, and blue, and…

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【We can understand chemistry on technology and electric appliance】

《Why does three dimensional look as if it popped out of the screen?》

…and each of the wave length is divided into two each other, then the image is assigned to left and right eye, so we can see the image. We can distinguish the image with the color film stuck to the lens.

Speaking of there dimensional, we think of glasses with red and blue lens which is familiar with us from long ago, and it’s a primitive one on the color filter.

As to the polarization, there are waves of light which sway for various directions, and…

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【We can understand chemistry on technology and electric appliance】

《Why does three dimensional look as if it popped out of screen?》

…and the film which makes the fixed light come through is adopted. Roughly speaking, the light is divided into two. The one moves for the specific angle alone, and the other does for rotating direction in a spiral way. As to the polarization, the film which make the two type of light alone come through is adopted.

As to what is called the way of shutter, the shutter of liquid crystal is combined into the 3D glasses, so the screen on the movie is changed to…

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【We can understand chemistry on technology and electric appliance】

《Why does three dimensional look as if it popped out of the screen?》

…so the screen on the movie changes to left and right each other, and the image for right eye alone, the one for the left eye alone are sent.

《There are various things in which a film is used for or digital is done. Why can we take a photograph?》

As to a camera which makes use of film, photo chemical 光化学 reaction in which material absorbs the light and changes it into something other is adopted. What is the film for the camera, and how is it made?

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【We can understand chemistry on technology and electric appliance】

《Why can we take a photograph?》

Fine particles from 臭化銀 is scattered in a liquid which gelatin is dissolved in and emulsion 乳液 is made, and the emulsion is put on a plastic film, and it’s the film for the camera.

Shining light on the film from the lens, and makes the film change chemically. We call it 感光. Using a reducing agent 還元剤, and changing the film into a black image.

By the way, the expression has lots of technical words, so it doesn’t ring a bell for me very much, so I’m going to try it again with my own way.

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【Why can we take a photograph with a camera?】

A landscape outside the house used to be shown on 障子 in a dark room vaguely upside down.

We can hardly see it in a recent modern resident at present, but we used to see it sometimes in a Japanese house long ago. Why did it happened?

Sunlight came through from a little hole of sliding storm shutter, and the landscape outside the house was shown on the 障子. It seems to have nothing to do with the camera in the least, but it’s the simplest mechanism on the camera.

In short, the dark room is equivalent to the body on the camera, and the little…

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【Why can we take a photograph with a camera?】

…and the little hole in the sliding storm shutter is the lens of the camera.

Thus as long at there is a box of which inside is dark and the box has a little hole from which the light comes through, the landscape outside comes through from the hole, and the landscape is shown on the wall of the box. It’s the principle on the what is call 針穴写真ピンホールカメラ.

Even if without having any lens, we can take a photograph as principle, but the photograph is out of focus, so a lens is attached, so we can take a beautiful photograph with the lens, but the…

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【Why can we take a photograph with a camera?】

…but the camera isn’t only indispensable but the film is necessary when taking the photograph. We can make the film record the light which comes through the lens. Taking out of the film which we took the photograph, and putting the film into the developing solution, its picture roses on the surface of the film. Then printing the photograph on a photographic paper, the photograph is completed.

As to a digital camera, the film isn’t used. Instead an image sensor is adopted. We call the image sensor CDC which is abbreviation of charge coupled device

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【Why can we take a photograph with a camera?】

To my sorrow, the expression on the book is too hard to understand for me, so I’m going to make use of the information in the internet like the next.

As to the digital camera, instead of the film, the element for taking a picture is used. I call it the element simply here.

After releasing the shutter, the light came through the lens and was on the element, and the light was changed into electron, and then was done into analog electric signal, but we can’t see it with our naked eyes, so we have to change it into the one which we can see.

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【Why can we take a photograph with a camera?】

The analog electric signal is dealt with the one which we can see. It is done with a circuit which handles an image. It’s recorded on the memory circuit.

The analog electric signal is changed into digital electric signal which we can see with our naked eyes.

The analog electric signal connects naturally smooth from the light to the dark part, on the other hand, the digital one connects as if it were a each of steps.

The less difference on each of steps are, the more smooth and sharper the digital electric signal is as image when seeing.

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【What’s difference between liquid crystal and plasma? Why does a TV work?】

Instead of TV in which a cathode ray tube ブラウン管 is adopted used to be the main stream, the one of liquid crystal or the one of plasma have spread over widely at present. Each of mechanism of reflecting image is different.

The TV on liquid crystal is made up with color filter, the panel of liquid crystal, and back light. The liquid crystal is the main part on the display. The liquid crystal is put into between two of glass, and polarization filter is attached outside of the glass.

The polarization is 偏光 in Japanese.

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【We can understand chemistry on technology and electric appliance】

《What’s difference between liquid crystal and plasma? Why does TV work?》

What’s the polarization? There’s light in electric field or magnetic field. The direction of shaking way is regular is called the polarization.

The polarization filter is attached outside the glass so as to control the direction of the light, to be the same direction with the way of arranging the molecules on liquid crystal.

When applying voltage there, changing the direction on the liquid crystal. Making the light from the back light come through…

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【We can understand chemistry on technology and electric appliance】

《What’s difference between plasma and liquid crystal? Why does TV work?》

Making the light from the back light come through or block, changing the way of the light come through, controlling the light, as if a wind blind was shut or opened, so the image on the screen of the liquid crystal is made.

On the other hand, plasma TV is simpler than the one of liquid crystal. In short, its mechanism is same as with the one of fluorescent light 蛍光灯. Red, green, and blue is called three primary color on the light. Plasma TV is a…

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【We can understand chemistry on technology and electric appliance】

《What’s difference between plasma and liquid crystal? Why does TV work?》

Plasma TV is a collection of small fluorescent light which gives off the three primary color. Its luminous body is in a separation, and is painted one by one, and the luminous body makes up the glass screen with electrode. As a result, the more the luminous body increases, the bigger its display becomes.

There is space a little on the painted luminous body, and xenon gas or neon gas is put into the small space. Applying voltage there, and causes to….

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【We can understand chemistry on technology and electric appliance】

《What’s difference between plasma and liquid crystal? Why does TV work?》

Applying voltage there and causes electricity on plasma to discharge, and ultraviolet rays are caused, and the luminous body is stimulated by the ultraviolet rays, then its image is made.

Plasm TV is different from the one of liquid crystal of which light source is the back light, its luminous body becomes luminous by discharging electricity, so the plasma TV has high image quality which is clear and three dimensional effect. It’s so big that its…

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【We can understand chemistry on technology and electric appliance】

《What’s difference between TV on plasma and crystal liquid? Why does TV work?》

The plasma TV is so big that its viewing angle is also large.

When looking at the screen from an angle, its brightness and color changes because the way of looking light from inside of the screen is different from the time when looking at it from the front. The viewing area is the place where the way of looking isn’t different.

As a result, even if when looking at the screen on plasma TV from an angle, we can enjoy clear image.

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