▎ 摘　　要

NOVELTY - Terahertz frequency band transparent piezoelectric film, comprises inorganic piezoelectric material, terahertz frequency band transparent conductive phase and terahertz frequency band transparent polymer material. USE - The piezoelectric film is useful in transparent ultrasonic transducer for terahertz photoacoustic microscopic imaging. ADVANTAGE - The piezoelectric film: improves the transmission efficiency of light in terahertz photoacoustic imaging, intensity of sound wave signal excited by object to be detected by laser irradiation and definition of terahethertz light sound imaging. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: preparing the terahertz frequency band transparent piezoelectric film, comprising (i) heating a polymer material with a transparent terahertz frequency band to a molten state, (ii) adding a transparent conductive phase in a terahertz frequency range into the polymer material in a molten state obtained in the resultant step as a conductive doped phase and an inorganic piezoelectric material, dispersing the conductive doped phase and inorganic piezoelectric phase in a polymer substrate in the molten state in a 0-dimensional mode, and stirring the conductive doped phase and inorganic piezoelectric phase under the condition of ensuring the molten state of the transparent polymer in the terahertz frequency range to uniformly disperse the conductive doped phase and the inorganic piezoelectric phase to obtain an inorganic piezoelectric material/conductive doped phase/polymer composite solution, (iii) hot-pressing and curing the resultant solution to obtain an inorganic piezoelectric material/conductive doped phase/polymer composite piezoelectric film, and (iv) coating electrodes which are transparent in the terahertz frequency band on two sides of the composite piezoelectric film obtained in the resultant step and carrying out alternating current polarization on the composite piezoelectric film, namely, mutually fusing continuous ferroelectric domains in the piezoelectric film by using an alternating electric field to reduce the number of the ferroelectric domains, further reducing the scattering of terahertz waves at domain walls, and finally preparing the piezoelectric composite film which is transparent in the terahertz frequency band. terahertz frequency band transparent ultrasonic transducer, comprising terahertz frequency band transparent piezoelectric film; and manufacturing the terahertz frequency band transparent ultrasonic transducer, comprising coating a composite terahertz frequency band transparent piezoelectric film on the upper side and the lower side of the composite piezoelectric film respectively, and then leading out tabs from the electrode layers respectively to obtain the product.