Apparatus for generating data for determining a property of a gemstone and methods and computer programs for determining a property of a gemstone

An method of generating data for use in determining a property of a gemstone, such as a cut diamond, the method comprising:

• supporting a gemstone at an observation position, such that, if the gemstone has an axis of symmetry, the gemstone is supportable such that the axis of symmetry is parallel to an axis X passing through the observation position;
• illuminating the gemstone with a spatially varied light pattern;
• causing relative rotation between the light pattern and the gemstone generally about the axis X;
• capturing, at each of a plurality of rotational positions, an image of light returned by the gemstone.

A computer-implemented method of comparing properties of gemstones, such as cut diamonds, the method comprising:

• receiving first image data in respect of a first gemstone and second image data in respect of a second gemstone, said first and second image data each comprising one or more images of said first and second gemstones, respectively;
• determining a property of each of said first and second gemstones in dependence on said first and second image data respectively;
• and
• simultaneously displaying one or more images of each of said first and second gemstones together with a representation of the determined property for each of said first and second gemstones.

An apparatus for comparing properties of gemstones, such as cut diamonds, the apparatus comprising:

• a support structure for supporting a gemstone placed at an observation position;
• illumination means arranged to illuminate a gemstone so placed;
• a camera arranged to capture an image of light returned by a gemstone and to output said images as image data;
• and
• a data processing device arranged to:
• receive first image data in respect of a first gemstone and second image data in respect of a second gemstone, said first and second image data each comprising one or more images of said first and second gemstones, respectively;
• determine a property of each of said first and second gemstones in dependence on said first and second image data respectively;
• and
• simultaneously display one or more images of each of said first and second gemstones together with a representation of the determined property for each of said first and second gemstones.

An apparatus for generating data for use in determining a property of a gemstone, such as a cut diamond, the apparatus comprising:

• a support structure for supporting a gemstone placed at an observation position, the support structure being arranged such that, if the gemstone has an axis of symmetry, the gemstone is supportable such that the axis of symmetry is parallel to an axis X passing through the observation position;
• illumination means arranged to illuminate a gemstone so placed with a spatially varied light pattern;
• rotation means arranged to cause relative rotation between the light pattern and the support structure;
• a camera arranged to capture, at each of a plurality of rotational positions, an image of light returned by the gemstone generally along the axis X and to output said images as image data.

An apparatus for generating data for use in determining a property of a gemstone, such as a cut diamond, the apparatus comprising:

• a support structure for supporting a gemstone placed at an observation position;
• illumination means arranged to illuminate a gemstone so placed with a spatially varied light pattern;
• rotation means arranged to cause relative rotation between the light pattern and the support structure generally about an axis X passing through the observation position;
• a camera arranged to capture, at each of a plurality of rotational positions, an electronic image of light returned by the gemstone generally along the axis X and to output said images as image data.

An apparatus for generating data for use in determining a property of a gemstone, such as a cut diamond, the apparatus comprising:

• a support structure for supporting a gemstone placed at an observation position;
• illumination means arranged to illuminate a gemstone so placed with a spatially varied light pattern;
• rotation means arranged to cause relative rotation between the light pattern and the support structure generally about an axis X passing through the observation position;
• a camera arranged to capture, at each of a plurality of rotational positions, an electronic image of light returned by the gemstone and to output said images as image data.