초록 ▼

An optical position sensor is provided for sensing the position of an object movable along a motion axis. The sensor comprises a light source, a support member, a beamsplitter, a variable filter, and a processor. The light source produces an optical beam that is directed to the beamsplitter. The bea

An optical position sensor is provided for sensing the position of an object movable along a motion axis. The sensor comprises a light source, a support member, a beamsplitter, a variable filter, and a processor. The light source produces an optical beam that is directed to the beamsplitter. The beamsplitter is fixedly coupled to the support member and optically coupled to the light source, and converts the optical beam into a reference beam and a subject beam. The beamsplitter projects the subject beam along a beam axis fixed relative to the support member. The variable filter is positioned along the beam axis, it is coupled to the object, and it is movably coupled to the support member to be movable along the motion axis in coordination with movement of the object for modulating the subject beam. The transmissivity of the variable filter is nonuniform along the motion axis to attenuate the subject beam in accordance with the position of the object. The processor is optically coupled to the beamsplitter to receive the reference beam and optically coupled to the variable filter to receive the subject beam. The processor compares the subject beam to the reference beam to determine the position of the object.

대표청구항 ▼

An optical position sensor for sensing the position of an object movable along a motion axis, said sensor comprising: a light source for producing an optical beam; a support member; beamsplitting means fixedly coupled to said support member and optically coupled to said light source for converting t

An optical position sensor for sensing the position of an object movable along a motion axis, said sensor comprising: a light source for producing an optical beam; a support member; beamsplitting means fixedly coupled to said support member and optically coupled to said light source for converting the optical beam into a reference beam and a subject beam, and for projecting the subject beam along a beam axis fixed relative to said support member; variable filter means positioned along the beam axis, coupled to the object and movably coupled to said support member to be movable along the motion axis in coordination with movement of the object for modulating the subject beam, the transmissivity of said variable filter means being nonuniform along the motion axis to attenuate the subject beam in accordance with the position of the object; a photodetector optically coupled to said beamsplitting means to convert the reference beam into a reference signal and optically coupled to said variable filter means to convert the subject beam into a subject signal; and comparing means coupled to said photodetector for comparing the subject signal to the reference signal to determine the position of the object.