Use and marking of three-in-one optical disc

Three-in-one disk is a tool for expressing syllables of Chinese characters, which is often used to compile ancient books or dictionaries. The triple disc consists of a circular disc surface and a disc edge. The disc surface is divided into three areas, and each area is marked with initials, finals and finals respectively. All Chinese syllables can be combined by rotating the disc. When using the triplet disk, it is necessary to correspond the initials, finals and vowels with the disk according to Chinese Pinyin. For example, when looking up the pronunciation of Chinese, you can first find the initial of "H", and then turn the dial to find the initial of "A" and the vowel of "an" to get the pronunciation of "hàn". When labeling the triple disc, it needs to be labeled according to the Chinese phonetic alphabet, that is, the initials are labeled first, and then the initials and finals are labeled. For example, the pronunciation of the word "Han" can be marked as "hàn". It should be noted that there are some special features in Chinese Pinyin, such as initials "zh, ch, sh" and finals "I, U, ü". Attention should be paid to details when using and labeling triplets.