Data storage device, data storage apparatus, and methods for storing and reading datas

A data storage apparatus, comprising:

• a data storage device, comprising:
• a light waveguide element;
• a protective element;
• and
• a plurality of data storage elements interposed between the light waveguide element and the protective element, wherein the light waveguide element irradiates light at a critical angle or more on the data storage elements, wherein each of the data storage elements comprises a transparent ferromagnetic element, which has been magnetized, disposed therein, and the magnetized transparent ferromagnetic element is movable by a magnetic field, and wherein when the magnetized transparent ferromagnetic element is moved close to the light waveguide element to allow light from the light guiding element to pass the data storage element, a first data is recorded, and when the magnetized transparent ferromagnetic element is moved away from the light waveguide element to prohibit light from the light guiding element to pass the data storage element, a second data is recorded;
• a light-emitting device emitting light towards the light waveguide element;
• a light sensor reading the first data or the second data stored in the data storage device by detecting light transmitted through the data storage element;
• and
• a magnetic writer applying the magnetic field to move the magnetized transparent ferromagnetic element to approach the light waveguide element to record the first data or get away from the light waveguide element to record the second data.

A method for reading data, comprising:

• irradiating light at a critical angle or more on a data storage element via a light waveguide element from a light source, wherein the data storage element comprises a transparent ferromagnetic element, which has been magnetized, disposed therein,
• wherein the magnetized transparent ferromagnetic element is positioned to allow frustrated total internal reflection or total internal reflection to occur in the data storage element for light from the light waveguide element,
• wherein when frustrated total internal reflection occurs in the data storage element and light from the light source is transmitted through a magnetized transparent ferromagnetic element and detected, a first data is read from the data storage element, and
• wherein when total internal reflection occurs in the data storage element and light is prohibited from the light source being transmitted through a magnetized transparent ferromagnetic element and detected, a second data is read from the data storage element.