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EP-4741808-A1 - IMAGE PICKUP TOOL FOR AESTHETIC DEFECT DETECTION

EP4741808A1EP 4741808 A1EP4741808 A1EP 4741808A1EP-4741808-A1

Abstract

The invention relates to an image-taking device 1 of a watch or jewelry component 90 for identifying defects such as scratches, comprising a frame on which the component 90 is placed, at least one circle of controllable directional LEDs 20 directed towards the component 90, a camera 10 for image taking, the internal walls of the frame comprising a multitude of controllable diffuse LEDs 70.

Inventors

  • Blanc, Sébastien
  • BONZON, Noémie
  • CANTALE, Nicolas
  • PAD, Pedram
  • HAZHAZ, Ihssan
  • SALEMBIEN, Tom
  • TODA MAS, Aleix

Assignees

  • Richemont International S.A.

Dates

Publication Date
20260513
Application Date
20241112

Claims (15)

  1. Image-capture device (1) of a watch or jewelry component (90) to identify a possible defect in the watch or jewelry component (90), comprising: - an image-capturing device (10), such as a camera, defining a principal optical axis (V) for image-capturing the watch or jewelry component (90), - a primary illumination source (20) with: - at least one first primary luminous element (21) defining a first primary inclination angle (A1) with respect to the principal optical axis (V) and a first primary radiation angle (121), and - at least one secondary illumination source (70) with: - a plurality of secondary light elements (71, 72, 73, 74, 75, 76) defining at least one principal angle of secondary inclination (P1) with respect to the principal axis (V) of image acquisition and at least one angle of secondary radiation (171, 172, 173, 174, 175, 176), in which at least one principal angle of secondary inclination (P1) is different from the first angle of primary inclination (A1), and in which at least one angle of secondary radiation (171, 172, 173, 174, 175, 176) is greater than the first angle of primary radiation (121), - a control unit arranged to control at least one first primary light element (21) and/or the plurality of secondary light elements (71, 72, 73, 74, 75, 76), so as to modify at least partially a shadow and/or a reflected light from the watch or jewelry component (90) in order to allow identification of the possible defect of the watch or jewelry component (90).
  2. Image capture device (1) according to the preceding claim, further comprising: - at least one second primary light element (22) defining a a second primary inclination angle (A2) with respect to the principal optical axis (V) and a second primary radiation angle (122), and in which the first primary tilt angle (A1) is less than the second primary tilt angle (A2) by a first predetermined value.
  3. Image capture device (1) according to any one of the preceding claims, wherein the control unit is arranged to control a light intensity of at least one first primary light element (21), at least one second primary light element (22) and/or the plurality of secondary light elements (71, 72, 73, 74, 75, 76).
  4. Image capture device (1) according to any one of the preceding claims, wherein the control unit is arranged to control an inclination of at least one first primary light element (21), of at least one second primary light element (22) and/or of the plurality of secondary light elements (71, 72, 73, 74, 75, 76), and preferably the inclination of the plurality of secondary light elements (71, 72, 73, 74, 75, 76) is predetermined and/or fixed.
  5. Image capture device (1) according to any one of the preceding claims, wherein the control unit is arranged to control a value of the first primary radiation angle (121), the second primary radiation angle (122) and/or the secondary radiation angle (171, 172, 173, 174, 175, 176).
  6. Image capture device (1) according to any one of the preceding claims, wherein the control unit is arranged to control an illumination sequence of at least one first primary light element (21), and/or at least one second primary light element (22) and/or the plurality of secondary light elements (71, 72, 73, 74, 75, 76) and/or one or more light elements of the plurality of secondary light elements (71, 72, 73, 74, 75, 76).
  7. Image capture device (1) according to any one of the preceding claims, wherein the primary illumination source (20) comprises: - a plurality of primary light elements (21), preferably arranged in a circular pattern, - a plurality of secondary primary light elements (22), preferably arranged in a circular fashion.
  8. Image capture device (1) according to any one of the preceding claims, wherein the primary illumination source (20) and/or the secondary illumination source (70) have a panel shape.
  9. Image capture device (1) according to any one of the preceding claims, wherein the image capture device (1) comprises an upper portion, a lower portion and/or at least one lateral portion, and in which the primary illumination source (20) is arranged on the upper portion, and the secondary illumination source (70) is arranged on the upper portion, the lower portion and/or at least one lateral portion.
  10. Image capture device (1) according to any one of the preceding claims, further comprising a rotating platform.
  11. Image capture device (1) according to any one of the preceding claims, wherein the primary illumination source (20) comprises at least one directional light element (21, 22, 23, 24, 25, 26) and the secondary illumination source (70) comprises at least one diffusing light element (71, 72, 73, 74, 75, 76).
  12. A method for identifying a defect in a watch or jewelry component (90) using the image-capturing device (1) according to any one of the preceding claims, comprising the following steps: - supply a watch or jewelry component (90), - illuminate the watch or jewelry component (90) by controlling the primary illumination source (20) of the device (1) and/or the secondary illumination source (70) of the device (1), - take at least one image of the watch or jewelry component (90) with the image capture device (1), - detect the defect in the watch or jewelry component (90).
  13. A method according to the preceding claim, further comprising the following step, prior to the defect detection step: - successively control the first primary light element (21) of the device (1) and/or the second primary light element (22) of the device (1) so as to modify at least partially a shadow and/or a reflection of light of the watch or jewelry component (90).
  14. A method according to claim 12 or 13, further comprising the following steps: - take at least one image, preferably multiple images, - to perform image processing, such as mathematical processing and/or processing by comparison, by addition and/or by subtraction of images.
  15. A method according to any one of claims 12 to 14, further comprising the following step: - send information concerning the possible detected defect of the watch or jewelry component (90) to an automatic system or to an operator.

Description

The present invention relates generally to the field of watchmaking, more particularly to the field of inspection of watch components, such as watch dials, as well as to the field of jewelry. Devices for capturing images of a watch component are known in the prior art. However, it is desirable to improve the performance and capabilities of these devices, particularly for the purpose of quality control or improving the aesthetics of watch or jewelry components. The present invention aims to provide an image capture device to identify any defects on a watch or jewelry component. In a first aspect, the invention relates to a device for taking images of a watch or jewelry component in order to identify a possible defect in the watch or jewelry component, comprising: an image-capturing device, such as a camera, defining a principal optical axis for capturing images of the watch or jewelry component, a primary light source with: at least one first primary luminous element defining a first primary angle of inclination with respect to the principal optical axis and a first primary radiation angle, and at least one secondary light source with: a plurality of secondary light elements defining at least one principal angle of secondary inclination relative to the principal image-capture axis and at least one angle of secondary radiation, in which at least one principal angle of secondary inclination is different of the first primary angle of inclination, and in which at least one secondary radiation angle is greater than the first primary radiation angle, a control unit arranged to control at least one first primary light element and/or the plurality of secondary light elements, so as to modify at least partially a shadow and/or a reflected light from the watch or jewelry component in order to allow identification of the possible defect of the watch or jewelry component. This allows for the development of an imaging device with improved performance and capabilities, particularly for quality control or enhancing the aesthetics of watch or jewelry components. A significant advantage of the invention is its ability to control the angle, power, and area of the illumination more precisely than prior art devices. This makes it possible to reveal defects, especially with positive contrast (i.e., white on a black background) or negative contrast (i.e., black on a white background). Furthermore, the high-resolution camera can also detect anomalies of extremely small size. For example, a camera or optical sensor with a resolution of 10 megapixels or higher is preferable. However, a camera or optical sensor with a lower resolution can also work. Therefore, particularly for presence/absence detection and the detection of obvious cosmetic defects, a minimum resolution of 1 megapixel is recommended. For cosmetic detection, a camera resolution of 5 megapixels is preferable. A shadow is understood to be a more or less dark area created by an opaque body that intercepts light rays, a partial shadow. The angle of radiation or emission angle refers to an angle that indicates the width of the light distribution. A large angle means a wide cone of light and a greater light intensity on the surface. The impact is weaker because the light is less concentrated. Conversely, if the angle of emission is small, the cone of light is narrow and the light intensity is proportionally greater. The light is ultimately concentrated on a smaller area. In other words, the invention relates to an imaging device for identifying a defect in a watch component, comprising an image-capturing element, such as a camera, defining a principal image-capturing axis of the watch component, a directional illumination panel with a first plurality of directional light elements defining a first directional illumination angle relative to the main image acquisition axis, and a second plurality of directional light elements defining a second directional illumination angle relative to the main image acquisition axis, the first directional illumination angle being different from the second directional illumination angle, at least one diffusive illumination panel with a plurality of diffusive light elements defining a principal diffusive illumination angle relative to the principal image-capture axis, different from the first and second directional illumination angles. Note that, preferably, a diffusive source exhibits a spatial emission distribution over an entire hemisphere, as opposed to directional sources, which produce a cone of light concentrating emission within a well-defined angle. The spatial emission profile of a diffusive source can be recognized by its Lambertian (or similar) emission distribution, as in the example of the figure 7 . In one embodiment, the invention relates to a device for taking images of a watch component to identify defects such as scratches, comprising a frame on which the component is placed, at least one circle of controllable directional