It's a drive optical drive that reads through a laser diode optical discs called CDs or CD The CD player It is an optical disc drive that reads optical discs called compact discs or CDs by means of a laser diode, whether they are audio CDs or computer CD-ROMs. When used to listen to music CDs, the CD player can be integrated into various types of portable or home devices, a car radio handset, etc. It can also be a separate device, portable or domestic, to be connected to a Hi-Fi system, an audio amplifier or headphones. In computing, the CD player is either an internal device located in the central unit or an external device connected to the computer by a USB USB The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : or FireWire Technology FireWire uses a time multiplex : time is cut into 125 microseconds (8,000 cycles per second), with the data cut into packets. In each installment are first transmitted the isochron packages (sound, video) and then the asynchronous packages (data). This system guarantees bandwidth for video streams thus avoiding jerky effects and other quality losses. port. A DVD drive (or DVD drive) is an optical disc drive used to work with digital data stored on DVDs. The arrival of the Video DVD (Digital Versatile Disc) revolutionized this small world, which appeared in 1 9 9 7 in the United States and in 1 9 9 8 in Europe, especially in France. Most DVD players can read multiple formats of optical discs. Operation Rotation of the disc The disk rotates by a servo engine at variable speed. Indeed, whether the section of track1 is in the center or periphery, the length of the sectors is always the same, therefore, unlike the vinyl disc, the scrolling of the data in front of the playhead must be constant. In simple speed, an area must be flown in 1/75th of a second. For a linear reading speed of 1.2 ms-1, the rotational speed varies from 458 tre min-1 to read the 50 mm diameter areas of the disk to 197 tr-min-1 to read the areas with a diameter of 116 mm (about) For comparison, a drive with a speed 16 times higher (CD-Rom 16x player) will see the speed of its disc vary between 7,328 tre min-1 and 3,152 tremin-1. Mechanical CD Philips with swivel arms. Moving the head The movement of the optical block is provided either by a swivel arm (Philips mechanics) or by a linear servo with very high precision because, on a possible total displacement of three centimeters4, it is able to adopt 600 different positions per millimeter. A lens from a CD player. Laser diode The laser diode emits in the infrared and is used for both writing and reading; however, the power of the beam is different if it is a reader or an engraver (a few milliwatts in reading versus 24 mW for a quadruple-speed engraver), moreover, it varies according to the speed of engraving. Optically directing beams The laser diode emits a beam to a prism (which can be characterized as a semi-transparent mirror); this prism sends the beam back at right angles to direct it to the lenses. The beam reflected by the disk (in polycarbonate) passes through the prism to excite the photodiode. Lenses The optical focusing block is on a mobile device whose movements are controlled by electromagnets. This system allows the position adjustment (sliding setting) of the focusing lens (mounted on a moving coil) in relation to the disk. This package is the goal. The lens, upstream of the lens, is used to concentrate the laser beam, so as to obtain a beam about one micrometer in diameter, in order to be able to read the microcuvettes (pits in English) of different lengths of the disc6. Since the diameter of the beam is not significantly wider than the wavelength of the incident beam, the focus of the beam must therefore be extremely precise. The manufacture of these lenses requires greater rigor but, unlike microscope lenses, for a single wavelength, that of the laser beam. Photosensitive diode This detects changes in reflected light. For a reader, this diode is used to read the disk information by detecting the variations of light received, characterized by the fronts generated by the succession of microcuvettes and intermediate smooth ranges (lands) of the disk. The high-frequency signal picked up by this receptive cell is called an eye diagram. Its decoding is used for several systems, including locating the position of the laser beam on the disk and assessing the speed of rotation of the disk, with a view to correcting it continuously (work of the enslavement circuits). For an engraver, it is also used to control the engraving. For a CD, the captured binary rate is standardized at 4.3218 MHz. DVD player Computer, DVD players are a computer input devices. They may be internal, which is integrated in the housing, or external, installed in their own case and connected to the computer through USB USB The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : or FireWire Technology FireWire uses a time multiplex : time is cut into 125 microseconds (8,000 cycles per second), with the data cut into packets. In each installment are first transmitted the isochron packages (sound, video) and then the asynchronous packages (data). This system guarantees bandwidth for video streams thus avoiding jerky effects and other quality losses. connector, and powered electricity sector. DVD players can be used in the salon to reproduce video content. They are then connected to a TV through HDMI HDMI HDMI is a fully digital audio/video interface that transmits uncompressed encrypted streams. HDMI is used to connect an audio/video source (DVD player, Blu-ray player, computer or game console) to a high-definition TV. HDMI supports all video formats, including standard, improved, high-definition definition and multichannel sound. HDMI encapsulanses video data by TMDS. or SCART SCART ( or péritel) SCART refers to a coupling device and an audio/video connector that has been mainly used in Europe. It allows you to simply plug in peripherals (TV) that have analog audio/video functions using a 21-pin connector. There are three types of connectors : the plug on the devices, the male/male cord and the extension cord. , S-Video, RCA RCA The RCA socket, also known as a phonograph or cinch socket, is a very common type of electrical connection. Created in 1940, it is still found today in most homes. It transmits audio and video signals. The acronym of RCA stands for Radio Corporation of America. Originally, the RCA plug was designed to replace the old telephone plugs of manual telephone exchanges. , and audio amplification by outputs analog audio system or by an optical type S/PDIF for digital sound cable. The DVD video frames are also able to read the CD audio type, or even VCD / SVCD and, for the most recent, CDs and data DVDs containing media files in various formats (especially MP3 music, JPEG for photos (, and DivX for video). Copyright © 2020-2024 instrumentic.info contact@instrumentic.info We are proud to offer you a cookie-free site without any ads. It is your financial support that keeps us going. Click !
Rotation of the disc The disk rotates by a servo engine at variable speed. Indeed, whether the section of track1 is in the center or periphery, the length of the sectors is always the same, therefore, unlike the vinyl disc, the scrolling of the data in front of the playhead must be constant. In simple speed, an area must be flown in 1/75th of a second. For a linear reading speed of 1.2 ms-1, the rotational speed varies from 458 tre min-1 to read the 50 mm diameter areas of the disk to 197 tr-min-1 to read the areas with a diameter of 116 mm (about) For comparison, a drive with a speed 16 times higher (CD-Rom 16x player) will see the speed of its disc vary between 7,328 tre min-1 and 3,152 tremin-1. Mechanical CD Philips with swivel arms.
Moving the head The movement of the optical block is provided either by a swivel arm (Philips mechanics) or by a linear servo with very high precision because, on a possible total displacement of three centimeters4, it is able to adopt 600 different positions per millimeter. A lens from a CD player.
Laser diode The laser diode emits in the infrared and is used for both writing and reading; however, the power of the beam is different if it is a reader or an engraver (a few milliwatts in reading versus 24 mW for a quadruple-speed engraver), moreover, it varies according to the speed of engraving.
Optically directing beams The laser diode emits a beam to a prism (which can be characterized as a semi-transparent mirror); this prism sends the beam back at right angles to direct it to the lenses. The beam reflected by the disk (in polycarbonate) passes through the prism to excite the photodiode.
Lenses The optical focusing block is on a mobile device whose movements are controlled by electromagnets. This system allows the position adjustment (sliding setting) of the focusing lens (mounted on a moving coil) in relation to the disk. This package is the goal. The lens, upstream of the lens, is used to concentrate the laser beam, so as to obtain a beam about one micrometer in diameter, in order to be able to read the microcuvettes (pits in English) of different lengths of the disc6. Since the diameter of the beam is not significantly wider than the wavelength of the incident beam, the focus of the beam must therefore be extremely precise. The manufacture of these lenses requires greater rigor but, unlike microscope lenses, for a single wavelength, that of the laser beam.
Photosensitive diode This detects changes in reflected light. For a reader, this diode is used to read the disk information by detecting the variations of light received, characterized by the fronts generated by the succession of microcuvettes and intermediate smooth ranges (lands) of the disk. The high-frequency signal picked up by this receptive cell is called an eye diagram. Its decoding is used for several systems, including locating the position of the laser beam on the disk and assessing the speed of rotation of the disk, with a view to correcting it continuously (work of the enslavement circuits). For an engraver, it is also used to control the engraving. For a CD, the captured binary rate is standardized at 4.3218 MHz.
DVD player Computer, DVD players are a computer input devices. They may be internal, which is integrated in the housing, or external, installed in their own case and connected to the computer through USB USB The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : or FireWire Technology FireWire uses a time multiplex : time is cut into 125 microseconds (8,000 cycles per second), with the data cut into packets. In each installment are first transmitted the isochron packages (sound, video) and then the asynchronous packages (data). This system guarantees bandwidth for video streams thus avoiding jerky effects and other quality losses. connector, and powered electricity sector. DVD players can be used in the salon to reproduce video content. They are then connected to a TV through HDMI HDMI HDMI is a fully digital audio/video interface that transmits uncompressed encrypted streams. HDMI is used to connect an audio/video source (DVD player, Blu-ray player, computer or game console) to a high-definition TV. HDMI supports all video formats, including standard, improved, high-definition definition and multichannel sound. HDMI encapsulanses video data by TMDS. or SCART SCART ( or péritel) SCART refers to a coupling device and an audio/video connector that has been mainly used in Europe. It allows you to simply plug in peripherals (TV) that have analog audio/video functions using a 21-pin connector. There are three types of connectors : the plug on the devices, the male/male cord and the extension cord. , S-Video, RCA RCA The RCA socket, also known as a phonograph or cinch socket, is a very common type of electrical connection. Created in 1940, it is still found today in most homes. It transmits audio and video signals. The acronym of RCA stands for Radio Corporation of America. Originally, the RCA plug was designed to replace the old telephone plugs of manual telephone exchanges. , and audio amplification by outputs analog audio system or by an optical type S/PDIF for digital sound cable. The DVD video frames are also able to read the CD audio type, or even VCD / SVCD and, for the most recent, CDs and data DVDs containing media files in various formats (especially MP3 music, JPEG for photos (, and DivX for video).