I have a cd player which can take replacement dvd-rom drives
I understand - Blu-ray uses blue lasers, which have a narrower beam than the red lasers in DVDs,
does anyone find they sound better with their discs for purely ordinary red book cds ?
if so can anyone recommend a dvd drive which is an upgrade
perhaps someone could put this into English
While a DVD uses a 650 nm red laser, Blu-ray Disc uses a 405 nm "blue" laser diode. Note that even though the laser is called "blue", its color is actually in the violet range. The smaller beam focuses more precisely, thus enabling it to read information recorded in pits that are less than half the size of those on a DVD, and can consequently be spaced more closely, resulting in a shorter track pitch, enabling a Blu-ray Disc to hold about five times the amount of information that can be stored on a DVD.
The lasers are GaN (gallium nitride) laser diodes that produce 405 nm light directly, that is, without frequency doubling or other nonlinear optical mechanisms.[76] Conventional DVDs use 650 nm red lasers, and CDs use 780 nm near-infrared lasers.
The minimum "spot size" on which a laser can be focused is limited by diffraction, and depends on the wavelength of the light and the numerical aperture of the lens used to focus it. By decreasing the wavelength, increasing the numerical aperture from 0.60 to 0.85, and making the cover layer thinner to avoid unwanted optical effects, the laser beam can be focused to a smaller spot, which effectively allows more information to be stored in the same area.[77] For Blu-ray Disc, the spot size is 580 nm.[78] This allows a reduction of the pit size from 400 nm for DVD to 150 nm for Blu-ray Disc, and of the track pitch from 740 nm to 320 nm.[77] See Compact Disc for information on optical discs' physical structure.
In addition to the optical improvements, Blu-ray Discs feature improvements in data encoding that further increase the amount of content that can be stored.[79]
I understand - Blu-ray uses blue lasers, which have a narrower beam than the red lasers in DVDs,
does anyone find they sound better with their discs for purely ordinary red book cds ?
if so can anyone recommend a dvd drive which is an upgrade
perhaps someone could put this into English
While a DVD uses a 650 nm red laser, Blu-ray Disc uses a 405 nm "blue" laser diode. Note that even though the laser is called "blue", its color is actually in the violet range. The smaller beam focuses more precisely, thus enabling it to read information recorded in pits that are less than half the size of those on a DVD, and can consequently be spaced more closely, resulting in a shorter track pitch, enabling a Blu-ray Disc to hold about five times the amount of information that can be stored on a DVD.
The lasers are GaN (gallium nitride) laser diodes that produce 405 nm light directly, that is, without frequency doubling or other nonlinear optical mechanisms.[76] Conventional DVDs use 650 nm red lasers, and CDs use 780 nm near-infrared lasers.
The minimum "spot size" on which a laser can be focused is limited by diffraction, and depends on the wavelength of the light and the numerical aperture of the lens used to focus it. By decreasing the wavelength, increasing the numerical aperture from 0.60 to 0.85, and making the cover layer thinner to avoid unwanted optical effects, the laser beam can be focused to a smaller spot, which effectively allows more information to be stored in the same area.[77] For Blu-ray Disc, the spot size is 580 nm.[78] This allows a reduction of the pit size from 400 nm for DVD to 150 nm for Blu-ray Disc, and of the track pitch from 740 nm to 320 nm.[77] See Compact Disc for information on optical discs' physical structure.
In addition to the optical improvements, Blu-ray Discs feature improvements in data encoding that further increase the amount of content that can be stored.[79]
