Patent ID: 8917382

Claim:
An electric distance meter, which emits outgoing light from a light source toward an object through an objective lens, and comprises a distance measuring optical system which measures a distance by receiving reflection light of the outgoing light from the object by a light receiver through the objective lens, the distance measuring optical system including: a condensing optical member configured to condense the reflection light from the objective lens; a light-receiving optical fiber configured to guide the reflection light from the condensing optical member to the light receiver in an optical path from the objective lens to the light receiver; and a cone prism configured to change a cross-section shape of a light beam and reduce an outer diameter of the light beam without generating a transmission deflection angle, and collect an inner part of annular light on an apex of a cone disposed at an outgoing side of the cone prism, the cone prism being provided between the objective lens and the condensing optical member.