LiTaO3（LT） is a kind of excellent pyroelectric materials that can be made into high performance pyroelectric detector.As the detector voltage response and detection rate inversely proportional to the thickness of the infrared sensing element

so thinning of LT crystals becomes a key factor of success.This design uses CMP method to produce 30 μm thickness of LT wafer and adopts charge integration method combined with computer automatic test system to test and calculate pyroelectric coefficient of different thickness and surface roughness crystals.Measured pyroelectric coefficient of crystal achieves 204 μC·m-2K-1

which shows great pyroelectric properties.