2.DVT is the abbreviation of digital video tape. DVT visual technology is a kind of tape storage and display technology, which can record sound and text simultaneously on the recording tape, and realize sound playback and text synchronous display through decoding chip. It is the domestic Daheng Ding Xin Science and Technology Company that completely conquered DVT vision technology, which owns the independent intellectual property rights of this technology and a number of patents and software copyrights related to it. The new DVT visual repeater with DVT technology can play the recording independently, see the content and translation of the original text, and consult the phonetic symbols and explanations of strange words at any time. It has created a brand-new language learning environment for foreign language practitioners.