Portable terahertz passive type color camera

Abstract

Provided in the invention is a portable terahertz passive type color camera comprising a terahertz type multi-beam quasi-optical mixer having N1*N2 pixels. The terahertz type multi-beam quasi-optical mixer carries out frequency mixing on a received terahertz radio frequency signal and a terahertz type oscillator signal to generate N1*N2-path mixing output signals, wherein the N1 and N2 are natural numbers larger than or equal to 1; and each path of mixing output signal corresponds to one pixel. According to the invention, the terahertz type multi-beam quasi-optical mixer is used as the main receiving and frequency conversion element and the integration level is high; and the two-dimensional large-scale array can be realized well. The size of the whole receiving machine is small and the weight is light. The target identification capability can be improved in a complex background environment; and real-time imaging can be realized. The good resolution ratio and the high sensitivity are realized.

Description

technical field [0001] The invention relates to the technical field of terahertz imaging, in particular to a portable terahertz passive color camera. Background technique [0002] Terahertz (THz) waves usually refer to electromagnetic radiation (1THz=10 12 Hz), which lies between microwaves and infrared radiation on the electromagnetic spectrum. Terahertz wave radiation can have the following characteristics in imaging applications: Terahertz wave radiation can penetrate many common non-metallic covering materials and detect hidden objects; the wavelength of terahertz wave is short enough to obtain higher imaging spatial resolution , or to achieve high-precision positioning of dangerous objects; electromagnetic radiation at terahertz frequencies is non-ionizing to organisms, so it is safer for the human body when used at an appropriate intensity; compared with microwave and millimeter wave imaging systems, under the same image resolution, Terahertz imaging systems are smal...

AI Technical Summary

Problems solved by technology

Using a single terahertz frequency, although the target can be effectively found and imaged, due to the complexity of the target radiation characteristics, there are problems in the effective target radiation intensity or feature recognition

[0005] 2. Usually a single-pixel scanning structure is used, which cannot be imaged in real time, and the resolution needs to be improved

For the horn antenna structure, due to the high frequency, it is difficult to process and the consistency is difficult to guarantee; in addition, the pixel pitch is constrained by the size of the horn antenna

For the quasi-optical lens, due to the use of a large lens, the phases of the signals received by the pixels located at different radii of the lens are different, and the phase information cannot be effectively used; and as the number of pixels (array scale) increases, the size of the lens increases, Not conducive to miniaturization

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