Patent ID: 8093915

Claim:
A device for absolute position measurement, comprising: a disk capacitive sensor, a signal processing unit, a data processing unit, and a display unit, wherein said disk capacitive sensor comprises a rough division sensor and a fine division sensor each having a pitch value; the pitch value of said rough division sensor is at least two times higher than that of said fine division sensor; said rough division sensor and said fine division sensor have the same zero position; grids of said rough division sensor and said fine division sensor are independent of each other, are free of electric coherence, and are fixed relatively to each other; the grids each have an exclusive absolute displacement value within a single pitch measurement range; said disk capacitive sensor has a transmission 3-piece structure comprising an emitting plate, a receiving plate, and a shielding plate; a rough division emitting pole corresponding to said rough division sensor, and a fine division emitting pole corresponding to said fine division sensor are installed on said emitting plate; a rough division receiving loop and a fine division receiving loop are disposed at a projection position on said receiving plate corresponding to said emitting pole; and a transmission window corresponding to said rough division emitting pole and said fine division emitting pole is opened on said shielding plate.