New vibration isolation platform was designed for keeping the precise optical instrument to work accurately. The displacement sensor which accuracy is 0.1nm was the measure apparatus. The changed value of spring was measured by displacement sensor
then the changed force of spring was calculated
then adjusted the force of electromagnet actuator according to the changed force of spring. At last the precise optical instrument was balanceable. The vibration of base was isolated. According to the analysis of theory and simulation
it could satisfy the request by applying the method of vibration isolation. This method is propitious to multilevel reduce vibration
and every vibration isolation platforms are absolute.