Patent ID: 7847931

Claim:
A measuring equipment utilizing terahertz pulse light, comprising: a terahertz light generator that generates terahertz pulse light; a terahertz light detector that detects terahertz pulse light; a first condensing optical system that condenses the terahertz pulse light generated by the terahertz light generator; and a second condensing optical system that condenses the terahertz pulse light diverging after being condensed by the first condensing optical system, onto the terahertz light detector, wherein: at least one of the first and the second condensing optical systems includes at least one lens having a positive or negative refractive power, the measuring equipment further comprising: a position adjusting mechanism that adjusts a position of the at least one lens on an optical axis when the terahertz light detector detects the terahertz pulse light having transmitted through a sample, the sample being arranged in a vicinity of a position of condensing the terahertz pulse light by the first condensing optical system; and a controlling unit that controls the position adjusting mechanism to move the position of the at least one lens on the optical axis so that a focused state of the terahertz pulse light having transmitted through the sample to the terahertz light detector is the same as a focused state of the terahertz pulse light to the terahertz light detector when no sample is arranged.