A novel optically readable infrared thermal imaging system that directly translates infrared image into visible image by using optically readable technology was presented. Its key part is a Fabry Perot Micro Cavity Infrared Detector Array(F P MCIRDA) based on MEMS(micro electro mechanical system) technology. Maximal thermo mechanical, opto mechanical sensitivity and temperature response of the movable micromirror are 6.47×10 -9 m/K, 1.53×10 8m -1 and 2.05×10 -4 , respectively, as theoretical analysis results for bi material Au/SiNx. System noise analysis indicates that the NETD of the present design and the expected limit of the NETD are 5.1K and 58mK, respectively. A 50×50 F P MCIRDA has been successfully fabricated by using bulk MEMS technology. The initial measurement results indicate that obvious displacement of the moveable micromirrors can be observed as the infrared radiation irradiates on. The operating principle of this system is verified successfully.