Accelerator sensor and accelerometer

An accelerometer, comprising an acceleration sensor, the acceleration sensor comprising a base, a cantilever, and a mass body fixed on the base through the cantilever, wherein:

• a shape of the mass body is a centrally symmetric shape;
• and
• the cantilever comprises four L-shaped arms, wherein the respective L-shaped arms comprise a long arm connected with the base, and a short arm connected with the mass body, and any adjacent two of the L-shaped arms are arranged symmetric to an axis;
• wherein the accelerometer further comprises:
• a substrate arranged opposite to and spaced from the acceleration sensor, an encapsulation structure encapsulating the acceleration sensor and the substrate, and a light source, an annular component, a photoelectric multiplier, and a signal processing circuit, all of which are located outside the encapsulation structure, wherein:
• the base comprises a hollow bushing running through an area facing the mass body in the acceleration sensor, wherein there is a first uni-mode optic fiber arranged in the hollow bushing, and an Extrinsic Fabry-Perot Interferometric (EFPI) cavity is formed between an end face of the first uni-mode optic fiber facing the mass body and the surface of the mass body facing the substrate;
• the light source is connected with a first port of the annular component through a second uni-mode optic fiber, and configured to provide the annular component with light;
• a second port of the annular component is connected with the first uni-mode optic fiber through a third uni-mode optic fiber, and configured to transmit the light, provided to the annular component by the light source, to the mass body through the first uni-mode optic fiber;
• a third port of the annular component is connected with the photoelectric multiplier through a fourth uni-mode optic fiber, and configured to provide the photoelectric multiplier with reflected light received through the first uni-mode optic fiber;
• and
• the signal processing circuit is connected with the photoelectric multiplier, and configured to calculate the acceleration from a signal output by the photoelectric multiplier.