COMPUTER SCIENCE AND ENGINEERING
COMPUTER ORGANIZATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Blue-red laser
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Blue-green laser
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Blue-violet laser
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Purple-green laser
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Detailed explanation-1: -While a DVD uses a 650 nm red laser, Blu-ray Disc uses a 405 nm “blue” laser diode. Although the laser is called “blue", its color is actually in the violet range.
Detailed explanation-2: -A disc in the DVD format can currently hold 4.7 gigabytes of data. Unlike DVD technology, which uses red lasers to etch data onto the disc, the Blu-ray disc technology uses a blue-violet laser to record information.
Detailed explanation-3: -A blue-violet laser, emitting at a wavelength of 405 nanometres, reads the pits. Because the laser used in a Blu-ray is of a shorter wavelength than that used in DVDs (635 or 650 nanometres), the spiral track can be more tightly wound. Thus, the Blu-ray disc can hold more information than the DVD.
Detailed explanation-4: -A blue laser is a laser that emits electromagnetic radiation with a wavelength between 360 and 480 nanometers, which the human eye sees as blue or violet.
Detailed explanation-5: -Blu-ray Disc uses a “blue” laser, operating at a wavelength of 405 nm, to read and write data. Optical digital recording disks.