Patent ID: 9057692
Filing Date: 2015-06-16
Classification: G01N

Abstract:
1. A measuring method with the device for measuring refractive index of medium based on optical delay technology comprising: a signal processing and controlling module, an optical transmitter module, and an optical receiver module; wherein the signal processing and controlling module controls the optical transmitter module to transmit an optical signal having a certain wavelength; the optical signal is injected into a medium to be measured; the optical signal is transmitted in the medium to be measured and delayed by the medium to be measured; after the optical signal delayed arrives at the optical receiver module, the optical receiver module transforms the optical signal delayed into an electrical signal, and the electrical signal is amplified and transmitted to the signal processing and controlling module by the optical receiver module; the signal processing and controlling module measures a delay time between transmitting the optical signal and receiving the optical signal; and a refractive index of the medium to be measured at the certain wavelength is calculated according to the delay time and a known length of the medium to be measured, comprising steps of: (1) measuring a first delay time of an etalon, i.e., t (2) replacing the etalon with a medium to be measured, and measuring a second delay time t (3) calculating an additional delay time of an optical signal with Δt=t (4) calculating the refractive index n