由于热释电晶体同时又是压电晶体,在其机械谐振频率附近,探测器的性能受到较大影响。A.M.Glass曾讨论了横向振动模压电谐振对LiTaO_3热释电探测器响应率的影响。本文讨论了纵向振动模压电谐振对面电极非自由悬吊型LiTaO_3热释电探测器介电噪声的贡献和由压电效应引起的振动噪声。 As the pyroelectric crystal is a piezoelectric crystal at the same time, the performance of the detector is greatly affected by its mechanical resonance frequency. A.M.Glass discussed the effect of transverse vibration mode piezoelectric resonance on the response rate of LiTaO_3 pyroelectric detectors. In this paper, the contribution of longitudinal vibration mode piezoelectric resonance to the dielectric noise of the non-free-suspended LiTaO_3 pyroelectric detector on the surface electrode and the vibration noise caused by the piezoelectric effect are discussed.