Magnetic disc CD-MO (Magneto-Optical) is an optical disk form that is stored using a magnetic field. In 1990, Philip and Sony defined them in their compableable CD standards (unofficially known as orange book Orangebook), CD-MO at least in theory, in theory, can support unlimited repetitive write.
CD-MO is made of ferrite and cobalt alloy. The MO disc is read according to the Ker effect. In the Ker effect, linear polarized light refers to under the influence of magnetic fields and distorts the polarizing surface. The Mo method changes the magnetic field characteristics of the optical disk surface micro-region, so the laser beam at the time of reading is different from the reflection and unchanged regions generated by the region.
When writing to the disc, the laser beam focuses on a very small point, and the substantially particles arranged when the alloy is heated to a specific temperature (referred to as the Curie point temperature) The ferromagnetic characteristics are lost. An electromagnet is provided with an electromagnet to change the polarity of the particles, and the difference is compiled into binary data storage. As with other optical vehicles, such as DVDs and other forms of CD, CD-MO is read by laser beams, which is more reliable than the hard disk and floppy disk. However, data stored in a strong environment in a magnetic field will be damaged.
But the standard is canceled soon, and even if there is any product that has been admitted to the world