Heterodyne fiber interferometer displacement measuring system and method

A heterodyne fiber interferometer displacement measuring system, comprising:

• a laser light source assembly configured to simultaneously emit measuring light and reference light;
• a first photoelectric detector, a first fiber coupler, a fiber ferrule, a plano-convex lens, a first polarizing beam splitting prism, and a first reflecting device which are sequentially provided on an optical path of the measuring light on the basis of first single mode fibers;
• and
• a second photoelectric detector, a second fiber coupler, a collimator, a second polarizing beam splitting prism, and a second reflecting device which are sequentially provided on an optical path of the reference light on the basis of second single mode fibers;
• wherein an object to be measured is fixed on the first reflecting device;
• wherein the measuring light sequentially passes through the fiber ferrule, the plano-convex lens and the first polarizing beam splitting prism to form two beams of light, one of which is fed back to the first fiber coupler via the first reflecting device, the first polarizing beam splitting prism, the plano-convex lens, the fiber ferrule and the first single mode fibers and the other of which is fed back to the second fiber coupler via the second polarizing beam splitting prism, the collimator and the second single mode fibers;
• wherein the reference light sequentially passes through the collimator and the second polarizing beam splitting prism to form two beams of light, one of which is fed back to the second fiber coupler via the second reflecting device, the second polarizing beam splitting prism, the collimator and the second single mode fibers and the other of which is fed back to the first fiber coupler via the first polarizing beam splitting prism, the plano-convex lens and the first single mode fibers;
• wherein the first fiber coupler couples the processed measuring light and reference light to the first photoelectric detector to form a measurement signal;
• and the second fiber coupler couples the processed reference light and measuring light to the second photoelectric detector to form a reference signal;
• and
• wherein displacement information of the object is determined according to the measurement signal and the reference signal.