Terahertz wave real-time imaging method and device based on optical parameter up-conversion

Abstract

The invention provides a terahertz (THz) wave real-time imaging method and a terahertz wave real-time imaging device based on optical parameter up-conversion. The method and the device are used for solving the difficulty of taking into consideration both imaging speed and signal-to-noise ratio and resolution of existing terahertz wave indirect imaging technologies. The imaging method comprises the steps that: a coherent THz wave after irradiating a target object and near-infrared pump light simultaneously incident a THz wave optical parametric up-conversion device; an obtained near-infrared idler light conjugate image is imaged and acquired by an optical imaging system, such that intensity, spectral distribution and wave-front phase information in the image are obtained; and the idler spectrum intensity, spectrum distribution and wave-front phase information are converted into THz wave spectrum intensity, spectrum distribution and wave-front phase information. According to the invention, scanning and pixel synthesis processes are not needed, such that high-speed real-time imaging is realized; spontaneous radiation occurs, and the signal-to-noise ratio is high. Weak THz signals can be imaged. The system structure is simple, and system reliability is good.

Description

technical field [0001] The invention belongs to the field of optical imaging, in particular to a terahertz wave real-time imaging method and device based on optical parameter up-conversion. Background technique [0002] Terahertz (THz) radiation generally refers to electromagnetic waves with a frequency between 0.1 THz and 10 THz, and its wave band is between microwave and far infrared. THz electromagnetic radiation has very unique properties, it can pass through various organisms, dielectric materials and gas phase substances, and the rotation frequency of many light molecules, the vibration mode of living functional groups of macromolecules and the resonance frequency of biomacromolecules are all in THz band. In addition, the THz spectrum also covers low-energy excitation phenomena of electronic materials, low-frequency vibration modes of condensed matter phase media, excitation phenomena such as phonons, magnons, plasmons, and liquid molecular vibrations of solid materia...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims to provide a terahertz wave real-time imaging method and its device based on optical parameter up-conversion, so as to solve the problem that imaging speed, signal-to-noise ratio and resolution cannot be balanced in the existing terahertz wave indirect imaging technology

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