MiniCD

Mini CDs, or pocket CDs, are CDs with a smaller diameter and one third the storage capacity of a standard 120 mm disc.

Amongst the various formats are the

In 1997 Dean Procter of Imaginet was offering business card sized square CDs with full screen hi-fi stereo video which played in quad speed CD ROMs or DVD drives with the centre well. A variety of laser cut shapes were developed.

When Mini CDs were first introduced in the United States, they were initially marketed as CD3, in reference to their approximate size in inches; larger CDs were called CD5, despite the fact that both CD specifications are defined solely in terms of metric units. Now, they are known as either Mini CDs or 80 mm CDs.

Most tray-loading CD devices have 2 'circular indentation'; one sized for a regular 120 mm CD, and a smaller, deeper circular indentation for Mini CDs to fit into, except for some Blu-ray players.

Devices that feature a spindle also support MiniCDs, as the disc can simply be placed onto the spindle as with a normal CD.

Some vertically aligned tray-loading devices, such as the older pre-slimline PlayStation 2 consoles when placed vertically, require an adapter for use with 80 mm CDs.

Most slot-loading CD drives are generally incompatible (the PlayStation 3 and Wii are exceptions), but adapters are available into which one can snap an 80 mm round Mini CD in order to extend the width to match that of a 120 mm CD, and thus work in many slot-loading devices.

A popular adapter model, Memorex 30183001, was discontinued in 2006.

Most CD players in the late 1980s and early 1990s didn't handle the Mini CD circular indentation and required the use of an adapter, or very careful placement of the CD in the exact middle of the tray. Not until after the major record labels discontinued them, did the CD Players start to have the 80 mm circular indentation as standard.

Since the mid-1990s, all tray loading players have circular indentation for the Mini CD.

Mini CD-R, Mini CD-RW: As of 2007, many manufacturers offer 80 mm CD-R and CD-RW discs for sale in retail electronics and office supply stores. These are sometimes marketed as "Pocket CD-R/CD-RW" (Memorex) or "Mini CD-R" (TDK). Most of the blank discs available in retail hold either 185 MB (21 minutes) or 210 MB (24 minutes) of data. The mini discs, despite having less weight and plastic, are generally more expensive than full size CD-R/CD-RW discs.

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