 Location of Low Island in the South Shetland Islands | |
  Dioptra Island Location of Dioptra Island  Dioptra Island Dioptra Island (South Shetland Islands) | |
| Geography | |
|---|---|
| Location | Antarctica |
| Coordinates | 63°13′01.7″S 62°11′33″W / 63.217139°S 62.19250°W |
| Archipelago | South Shetland Islands |
| Area | 0.92 ha (2.3 acres) |
| Length | 290 m (950 ft) |
| Width | 45 m (148 ft) |
| Administration | |
| Administered under the Antarctic Treaty | |
| Demographics | |
| Population | uninhabited |
Dioptra Island (Bulgarian: остров Диоптра, romanized: ostrov Dioptra, IPA: [ˈɔstrov diˈɔptrɐ]) is the conspicuous 290 m long in east-west direction and 45 m wide rocky island off the northwest extremity of Low Island in the South Shetland Islands, and separated from Beslen Island on the southeast by a passage narrowing to 21 m at points. Its surface area is 0.92 ha.
The feature is named after the classical surveying instrument dioptra, and in association with other names in the area deriving from the early development or use of geodetic instruments and methods.