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A standard CD-R has a storage capacity of 600MB or 650MB (not MiB). Non-standard CD-Rs are available with capacities of 700MB, which they achieve by exceeding the tolerances specified in the Orange Book CD standards.

The polycarbonate disc contains a spiral groove to guide the laser beam upon writing and reading information. The disc is coated on the side with the spiral groove with a very thin layer of a special dye and subequently with a thin, reflecting layer of silver, a silver alloy or gold. Finally, a protective coating of a photo-polymerizable lacquer is applied on top of the metal reflector and cured with UV-irradiation.

A specially designed type of CD-ROM drive, called a CD-R drive, CD burnerA CD burner is an internal or external writable Compact Disc drive that can be attached to a computer. It lets you write and read files from a computer on to compact disc media, and is standard equipment in most new computers. The burner describes the pro, or CD writer can be used to write CD-Rs. A laser is used to etch ("burn") small pits into the dye so that the disc can later be read by the laser in a CD-ROM drive or CD player. The laser used to write CD-Rs is an infraredInfrared IR radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. The name means "below red" (from the Latin infra "below"), red being the color of visible light of longest wavelength. laser which emits laser radiation at a wavelengthThe wavelength is the distance between repeating units of a wave pattern. It is commonly designated by the greek letter lambda (λ). In a sine wave, the wavelength is the distance between peaks: The x axis represents distance, and I would be some va of 780 nm. The reflectivityIn optics, reflectivity is the reflectance (the ratio of reflected power to incident power, generally expressed in decibels or percentage) at the surface of a material so thick that the reflectance does not change with increasing thickness; i. the intrins in the pit area is different (lower) than for the unchanged dye area, because the refractive indexThe refractive index of a material is the factor by which electromagnetic radiation is slowed down (relative to vacuum) when it travels inside the material. For a non-magnetic material, the square of the refractive index is the material's dielectric const of the dye is lowered upon "burning" a pit. Upon reading back the stored information, the laser operates at a low enough power not to "burn" the dye and an optical pick-up records the changes in the intensity of the reflected laser radiation when scanning along the groove and over the pits. The change of the intensity of the reflected laser radiation is transformed into an electrical signal, from which the digital information is recovered ("decoded"). The decomposition of the dye in the pit area through the heat of the laser is irreversible (permanent). Therefore, once a section of a CD-R is written, it cannot be erased or rewritten, unlike a CD-RWIn computing and data storage, Compact Disc Rewritable or CD-RW is a rewritable version of CD-ROM. Whereas standard prerecorded compact discs have their information permanently stamped into an aluminium reflecting layer, CD-RW discs have a phase-change re. A CD-R can be recorded in multiple sessions.

The CD-R was invented in 19881988 is a leap year starting on Friday (click on link for calendar). Events January January 2 Georgia celebrates its bicentennial statehood. January 9 Connecticut celebrates its bicentennial statehood. January 26 Australia celebrates its bicentennial day. by the Japanese company Taiyo Yuden . First CD-Rs were produced in 19941994 is a common year starting on Saturday, and was designated the International year of the Family''. Events January events January 1 North American Free Trade Agreement (NAFTA) goes into effect January 6 Nancy Kerrigan is clubbed on the right leg by an. Among the first manufacturers were the companies Taiyo Yuden, Kodak, Memorex , Maxell, and TDK. Since then, the CD-R was further improved to allow writing speeds as fast as 54x ( as of 2004) relative to the first 1x CD-Rs. The improvements were mainly due to optimisation of special dye compositions for CD-R, groove geometry, and the dye coating process. Low-speed burning at 1x is still used for special "audio CD-Rs", since CD-R audio recorders got standardized to this recording speed.

There are three basic formulations of dye used in CD-Rs.

1. Cyanine dye s were the earliest ones developed, and their formulation is patented by Taiyo Yuden. Cyanine dyes are naturally green in color, and are chemically unstable. This makes cyanine discs unsuitable for archival use; they can fade and become unreadable in a few years. Many manufacturers use proprietary chemical additives to make more stable cyanine discs.

1. Azo dye CD-Rs are blue in color, and their formulation is patented by Verbatim . Unlike cyanine, azo dyes are chemically stable, and typically rated with a lifetime of decades.

1. Phthalocyanine dye CD-Rs are usually silver or gold. The patent on pthalocyanine CD-Rs is held by Mitsui. These are also chemically stable, and often given a rated lifetime of hundreds of years.

Note that unfortunately, many manufacturers add additional coloring to disguise their cyanine CD-Rs, so you cannot determine the formulation of a disc based purely on its color. Similarly, a gold reflective layer does not guarantee use of phthalocyanine dye. Note also that rated CD-R lifetimes are estimates based on accelerated aging tests, and lifetime can vary considerably based on how you store the discs.

For optimum lifespan, CD-Rs should be stored vertically to prevent warping, inside archival plastic cases which use a ridged ring around the spindle which grips the disc. This ridge prevents the surface of the disc from coming into contact with anything during storage. Discs should be stored in cool, dark conditions, with controlled humidity. Avoid using any kind of label on the CD surface, and avoid use of printed inserts using anything other than water-based inks.

Although the CD-R was initially developed in Japan, most of the production of CD-R had moved to Taiwan by 1998. Taiwanese manufacturers supplied more than 70% of the worldwide production volume of 10.5 billion CD-Rs in 2003.

There was some incompatibility with CD-Rs and older CD-ROM drives. This was primarily due to the lower reflectivity of the CD-R disc. In general, CD drives marked as 8x or greater will read CD-R discs. Some DVD players will not read CD-Rs because of this change in reflectivity as well.

see also: CD-ROM, DVD, DVD-R, DVD plus R, DVD plus R DL, CD burner, Spindle