Optical digitizer/position measuring device
First Claim
1. An optical measuring system comprising at least one optical fiber transducer and an object having a surface, the measuring system being adapted to measure position, angle, and the time dependence of these quantities in at least one dimension between said transducer and said surface of the object,said measuring system further comprising at least one light-emitting means and said at least one optical fiber transducer to illuminate said surface, at least one photo-detector means to sense light from said light-emitting means emanating from said surface, andat least one electronic unit for controlling the light emitted by said light-emitting means and evaluating the signal variations from said photo-detector means,said surface being provided with an optically detectable pattern defined by variations of an optical propertysaid variations of at least one of said optical properties of said surface are arranged to have at least three different amplitude values in at least one direction across said surface, said amplitude values being defined by the difference between a local maximum and a local minimum of said at least one optical property of said optically detectable pattern, said local minimum lying to one side of said local maximum in said at least one direction,said at least three different amplitude values are arranged to occur in a predetermined order in said at least one direction,said amplitude values, which are obtained when said at least one optical fiber transducer is displaced relative to said surface, are arranged, through the opto-electronic arrangement of said light-emitting means, said at least one optical fiber transducer and said photo-detector means, to be transformed into electric signal amplitudes by said photo-detector means, andsaid signal amplitudes being evaluated by said electronic unit to determine the position, the angle and/or the direction of movement of said at least one optical fiber transducer relative to said surface of the object.
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Accused Products
Abstract
The invention relates to an optical transducer for measuring position, angle, and the time dependence of these quantities in one, two or three dimensions, with at least one fiber optical transducer having light-emitting means which feeds incident light to an object on which the measurement is to be effected, a photo-detector which senses light emanating from the object after said incident light has been influenced by the object and an electronic unit partly for controlling the light-emitting means, and partly for evaluating the output of the photo-detector, the output signal being dependent on the variations in light transmission, light absorption, light reflection and/or photo-luminescence of a pattern on the object. The variations of one or more of the optical properties of the pattern in at least one direction have at least three different amplitude values which occur in a specific order, and that the relative amplitude values between variations of the optical properties, which variations are consecutive in space, are detected and evaluated by the electronic unit for determining the direction of movement and the position of the transducer relative to the object.
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Citations
12 Claims
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1. An optical measuring system comprising at least one optical fiber transducer and an object having a surface, the measuring system being adapted to measure position, angle, and the time dependence of these quantities in at least one dimension between said transducer and said surface of the object,
said measuring system further comprising at least one light-emitting means and said at least one optical fiber transducer to illuminate said surface, at least one photo-detector means to sense light from said light-emitting means emanating from said surface, and at least one electronic unit for controlling the light emitted by said light-emitting means and evaluating the signal variations from said photo-detector means, said surface being provided with an optically detectable pattern defined by variations of an optical property said variations of at least one of said optical properties of said surface are arranged to have at least three different amplitude values in at least one direction across said surface, said amplitude values being defined by the difference between a local maximum and a local minimum of said at least one optical property of said optically detectable pattern, said local minimum lying to one side of said local maximum in said at least one direction, said at least three different amplitude values are arranged to occur in a predetermined order in said at least one direction, said amplitude values, which are obtained when said at least one optical fiber transducer is displaced relative to said surface, are arranged, through the opto-electronic arrangement of said light-emitting means, said at least one optical fiber transducer and said photo-detector means, to be transformed into electric signal amplitudes by said photo-detector means, and said signal amplitudes being evaluated by said electronic unit to determine the position, the angle and/or the direction of movement of said at least one optical fiber transducer relative to said surface of the object.
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12. A method of optically sensing the movement of at least one fiber optical transducer means relative to a surface of an object in two non-parallel directions, comprising providing said surface with a pattern formed from discrete bands extending in each said direction and uniformly spaced apart in the other said direction, modifying incident light in a first wavelength range by the bands in one direction and modifying incident light in a second wavelength range by the bands in the other direction, modifying differently the incident light in the respective wavelength band by the adjacent bands in each said direction, receiving modified incident light from said bands in said at least one fiber optical transducer as the latter is moved over the surface, and determining from the received modified light in the respective two wavelength ranges the precise movement of said at least one optical transducer across the bands in the respective two directions.
Specification