Definition

1. Noun:
   • Tacheometer / Tachymeter: A surveying instrument or a type of lens used to measure distances from the observer's location to a distant point or object.
   • Rangefinder lens: In optics, a lens system designed for determining the distance to an object viewed through it.

Usage Examples

• Noun:
  • Nhà địa chất sử dụng trắc viễn để đo khoảng cách tới vách núi. (The geologist uses a tacheometer to measure the distance to the cliff face.)
  • Ống kính trắc viễn trên máy ảnh này rất chính xác. (The rangefinder lens on this camera is very accurate.)

Advanced Usage

• The term is technical and primarily used in fields like surveying, geodesy, optics, and photography. It is not common in everyday conversation.

Variants and Related Words

• Máy trắc viễn (n): Tacheometer/theodolite (the complete instrument).
  • Máy trắc viễn là thiết bị quan trọng trong trắc địa. (The tacheometer is an important device in surveying.)

Synonyms

• Rangefinder: A device for estimating distance.
• Tacheometer: A surveying instrument for measuring distances.
• Tachymeter: An instrument for rapid measurement of distance, direction, and elevation.

Notes on Usage

• "Trắc viễn" is a compound Sino-Vietnamese word (trắc = to measure, viễn = far). It is a specialized term.
• It is most accurately translated as a rangefinder in a general optical context or a tacheometer in a precise surveying context. The specific meaning depends on the technical field.