What is a Compact Disc?

An optical disc is an item that uses optical information as a storage medium and is used to store data. Non-rewritable optical discs, such as CD-ROM, DVD-ROM, etc .; and rewritable optical discs, such as CD-RW, DVD-RAM, etc.

How was the disc created? Many people may not be able to answer this question. Our desktop computer can be manufactured by assembling. For example, the processor, memory, hard disk, motherboard and other accessories are installed in the chassis to form a computer. A motherboard is wired, patched, soldered,

From the main structure, the structure of CD and DVD discs is the same, but their thickness and materials are different. In the introduction above, we mentioned that the thickness of a CD disc is 1.2mm. Can this thickness be changed? The answer is no.

With the widespread use of VCD and DVD players, almost every home has some compact discs. The high-definition, realistic sound quality and clear images of compact discs have been loved by many people, and proper maintenance of the compact discs will make you enjoy the original sound for a long time.

Due to the influence of weather and temperature, the surface of the disc may sometimes condense moisture. Before use, a clean and soft cotton cloth should be used to gently wipe the surface of the disc.

The disc should be placed as far as possible from dust and away from magnetic fields. It is advisable to pinch the edge and center of the disc when removing it.

If dirt is found on the surface of the disc, you can use a clean cotton cloth dipped in a special cleaner to gently rub it from the center to the outer edge of the disc. Do not use

1)

Originally, optical discs were only readable, but new technology allows users to use optical discs for recording. Optical discs will become more and more popular in the field of music recording and playback. A new technology, Digital Versatile Disc (DVD), can store more video for playback in the same space.

CD variants include:

• CD-ROM

• CD-i

• CD-RW

• CD-ROM XA

• DW

• Photo CD

• Video CD ^[1]

  CD-ROM duplication is not mysterious and can be simply divided into five steps:

  (1) pre-made master film; (2) master film making; (3) electroforming; (4) reproduction; (5) printing; (6) packaging

  The reason why a CD-ROM disc is a single-sided disc is not a double-sided disc. It is not technically impossible, but the cost of making a double-sided disc is higher than the cost of making two single-sided discs. Therefore, one side of a CD-ROM disc is dedicated to printing trademarks and the other side is used to store data. The laser beam must pass through the transparent substrate to reach the pit and read the data. Therefore, any contamination on the surface of the side where the data is stored in the disc will affect the data read performance. Coding In order to store data on a physical medium, the data must be converted into a physical representation suitable for storage on the medium. Conventionally, various codes obtained after data conversion are called channel codes. They are called channel codes because these codes go through the communication channel. Channel codes are not a new concept.

  1.The birth of CD

  CD stands for Small

  1

  Photo Compact Disk

  CD

  2

  Super Audio Compact Disk

  Super Audio CD

  3

  Special Interest Group on CD-ROM Applications and Technology

  Optical Disc Application and Technology Special Interest Group

  4

  Compact Disk-Extended Architecture

  Extended Architecture CD

  5

  Compact Disk-Write Once

  Write-once disc

  6

  Compact Disc Re-Writable

  Rewritable disc

  7

  Compact Disk File System

  CD file system

  8

  Compact Disk

  CD

  9

  Compact Disk-Real Time Operating System

  CD-RTOS

  10

  Compact Disk-Read Only Memory Data Exchange Standard

  CD-ROM Data Exchange Standard

  11

  Compact Disk-Recordable

  CD burner

  12

  Compact Disk-Magneto Optical

  Magneto-optical disc

  13

  compact disk-interactive

  Interactive disc

  14

  compact disc-digital audio

  A research team at the University of Tokyo in Japan has found a material that can be used to make cheaper, much larger super discs that can store up to 5,000 times the capacity of a typical DVD.

  Shin-ichi Ohkoshi, a professor of chemistry at the University of Tokyo and the host of the research team, said on the 24th that this material is usually a ferrous metal that can conduct electricity and will turn into a brown semiconductor when clicked by light. This is a new type of transparent titanium oxide. It is irradiated by light at room temperature and can be arbitrarily transformed between metals and semiconductors, thus generating the function of storing data.

  Otsuchi Shinichi said that this material is a new generation of optical storage devices

  Compact disc table lamp

  The strong reflectivity on the data side of the disc is why we use it as a material for the lampshade

  See what this is? A "disc tree"! Sometimes we just need to use our brains and don't need to work hard to make amazing artworks.

  People who have used computers for several years will have a large number of discs. Usually we throw away these waste discs and inadvertently pollute the environment with these waste plastics.

  Can not be used, thrown and no place to throw, is it really so difficult to deal with discs? Is there any way to make the most of them and add a little glory to our lives?

  CD CD earring holder for CD

  If you open a jewelry store or are a fashion lover, how to place earrings must often bother you. If you put the earrings in the box, they can be a bit cumbersome to wear-first of all, it is difficult to find them, and if they are wrapped around, it is even more troublesome. I can teach you a way to make a earring holder with a discarded CD, which is both beautiful and practical. It would be too romantic to give her a girlfriend's birthday.

  First, prepare a paper tube that is slightly larger than the CD center hole, or exactly the same size as the CD center hole. Measure the size of the center hole of the CD. If it is larger than the size of the paper tube, use a wooden file to carefully expand the center hole. Then put the CD data face up on the prepared paper tube (as close as possible to the bottom of the paper tube), and then insert 3 pins in different directions on the paper tube to support the CD, so that the base of the earring holder is ready .

  Similarly, take 3 to 4 CDs, enlarge the center hole, and then use drill or wood to punch a few small holes on the edge of the CD. If there are many earrings, you may wish to play a few more. Repeat the above steps, put the CD on the paper tube, and support it with a pin.

  If you put the earring stand in the display window, under the light, the light of the CD and the gemstone of the earrings complement each other, the effect is great.

  CD CD as light reflector

  Speaking of light reflectors, everyone may be a little confused. In fact, all we have to do is install the CD into the lampshade. In this way, the reflection effect of light is enhanced, and the light looks brighter.

  First, measure the size of the lampshade, and see how many CDs are needed. The CD can be evenly mounted on the inner side of the lampshade (usually 4 to 5 is enough).

  Then make 4 holes symmetrically at the edge of the CD (3 o'clock, 6 o'clock, 9 o'clock, 12 o'clock). It is also important to be careful not to shatter the CD when punching holes.

  Look at the size of the lamp cover again, determine the installation position of the CD, put the CD in the lamp cover, punch holes in the corresponding position of the lamp cover, and pass the ribbon through the hole of the corresponding position of the CD and the lamp cover, and fix the CD on the lamp cover (3 points with 6 Point, 9 points to 12 points, or 3 points to 6 points, 6 points to 12 points, depending on what shape you prefer), pay attention to the connector of the ribbon inside the lampshade, if the connector is outside, it does not matter , May wish to tie a bow, also beautiful.

  Fix all the CDs on the lampshade, and the light reflector will be ready. Connect the power supply and try it, and the brightness will be significantly improved!

  It turned out that some people installed a CD as a reflector on the back of a motorcycle, and also used this principle, but it is obviously more fashionable to use a CD as a lampshade, right?

  CD CD with CD as table lamp

  The idea of making a CD table lamp came from an accidental discovery. The company I worked for had a lot of CDs. These CDs were piled on windowsills, and almost all the windows were blocked. When the sun shined through the CDs, it was light blue, making people feel refreshed. Since then, I have been thinking that it would be great if I could use a CD as a desk lamp.

  However, the realization of this idea is still very difficult. First of all, there must be a large number of CD disks. Secondly, there must be suitable lamps. The size of the tube must not be too thick and the wattage cannot be too large. . After years of accumulation, I finally prepared all the materials and made a unique dream crystal lamp.

  First, prepare an emergency light. The size of the tube is slightly smaller than the center hole of the CD. Disassemble the emergency light, and keep the fluorescent tube, tube connector, battery box, switch, and circuit components for future use.

  Then make the base of the desk lamp. Take a piece of plywood and saw 3 to 4 circles that are slightly larger than the CD disc, glue them with white latex and polish them smoothly. Dig a hole under the base to fit the battery box, and drill a small hole in the battery box for wiring. A hole was staggered above the base to fix the circuit board here. Dig a round hole in the center of the base to fix the lower tube connector, and then fix the power switch to the side of the base, so that the base is ready.

  Then, the lamp holder of the desk lamp is made. First check whether the size of the CD center hole is slightly larger than the lamp tube. If the size of the CD center hole is small, use a file to enlarge the center hole, and then make a small hole (for wiring) at a distance of 5CM from the center. After all the CDs are processed, connect the base circuit and the lower connector of the lamp tube, fix the lamp tube, and place the first piece of CD on the lamp tube with the light side facing up. Pass through the hole, apply a small amount of white latex to the surface of the first CD, cover another CD, and gently squeeze with the palm of your hand. Repeat this step until the CD thickness reaches the desired height.

  Finally, connect the connector above the lamp, install the battery, and turn on the switch. The dream crystal lamp is ready. Finally, I would like to remind you again that the power of the lamp should not be too high, otherwise the CD will be burnt and the scenery will be ruined.

  Compact disc

  We can get some inspiration from making disc holders from discs-is it possible to make wind chimes from discs?

  First, make a few holes on the edge of the disc, string the discs together with a string, attach a small bell underneath, and hang it on the window sill to turn it into a good-looking wind chime, simple and cheap.

  Compact disc

  Take apart the small quartz alarm clock at home, leave the movement and the hour and minute hands, install these three on the compact disc, and make the scale according to your preference on the compact disc, put the battery, a simple and personalized small clock That's it.

  Compact disc with flower pot

  There is a lack of green in the office. Some friends may want to raise potted flowers, but the pots not only occupy a large area, but also easily stain the table. Is there anything in the office that can be used as a flower pot? That's waste discs, paper cups and tape!

  First find four waste discs, put them in a row one by one, leave a 2 mm gap between each disc, and then stick it with tape to fix the four discs, and then turn their data inward and roll them into A circle.

  Then use the fifth disc with tape and make a bottom for this flowerpot-so we have a disc "box" with only the top opening.

  We know that the data side of the disc is bright, but the other side is not good. In order to avoid this problem, we took out four more discs, with the data facing outwards, and affixed to the four sides of the flowerpot.

  Take a paper cup filled with water and put it in a flower pot, then take out a disc, pass a spider plant through its middle, and gently place it on the flower pot to ensure that the root of the spider plant has been soaked in the paper cup. In the water.