Main categories of optical laser disks are CD-ROM,WORM Disk/CD-Record able(CD-R) Disks,CD Read/Write(CD-RW) Disk,Digital Video(or Versatile)Disk(DVD).
As different people have different ideas on what is best you may be better off to go to the websites of each of the companies you listed andlooking for yourself. Internal optical disk drive are now essential these days as the Digital Versatile Disks or optical disks are the main way of installing programs, including operating systems, onto computers
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Free-electron lasers were invented at Stanford University by John Madey. While these lasers share the same optical properties as conventional lasers, the main difference between the two is the principal they use to form the beam.
The main categories of food are:CarbohydratesFatsProteinsVitaminsMinerals
The main purpose of a laser is to focus electromagnetic radiation (light) on to a single point.
The three main categories of fashion are haute couture,ready-to-wear and mass market.
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lens
Optical memory is an early form of computer memory. It involves the use of an optical system for the writing and reading of data to and from a computer's main memory.
Main products are Optical Windows, Mirrors, Prisms, Lenses, waveplates and Color Filters,
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