A method for identifying precious stones using a test device

Abstract

The invention relates to a method for identifying precious stones using a test device, comprising a body and a tray to carry the stones to be examined into the body, a UVC light source, a UVA light source, a camera that captures images from the stones placed in the body, a control unit that processes data from images captured by the camera, and a screen connected through a network connection from the control unit for data transmission. The identification method involves capturing images under a light source with a 222 nm UVC wavelength through a camera at different lens apertures and selecting the most accurate image to transmit to the control unit; the control unit runs an image processing algorithm to examine the fluorescence and phosphorescence emissions of the precious stones, enhancing the accuracy of the data obtained by capturing images under a light source with a 365 nm UVA wavelength through the camera at different lens apertures and transmitting them to the control unit; the control unit runs the image processing algorithm to examine the fluorescence and phosphorescence emissions; the accuracy of identifying precious stones is improved by adjusting the sensitivity setting defined in the image processing algorithm.

Description

[0001] A METHOD FOR IDENTIFYING PRECIOUS STONES USING A TEST DEVICE

[0002] TECHNICAL FIELD

[0003] The invention relates to a method used for identifying precious stones and distinguishing between natural and synthetic diamonds. The device is also suitable for the analysis of other precious stones that glow under UV light and valuable objects of different shapes such as rings and bracelets.

[0004] STATE OF THE ART

[0005] Natural stones are formed under natural conditions of very high pressure and temperature, making them rare and highly valuable jewels. As an alternative to natural stones, synthetic stones produced in laboratories are commonly used in the jewelry field due to their affordability. Synthetic stones are optically, physically, and chemically similar to natural stones to a degree that they are indistinguishable to the naked eye.

[0006] On the other hand, diamonds, which are among the most commonly used precious stones in the jewelry sector, are classified based on qualities such as clarity and color. Although they may appear the same at first glance, there are differences in the shade of their colors, variations in their fluorescent colors, or the size of inclusions within them.

[0007] It is not possible to distinguish these stones from one another by simple means without gemological analysis. Differences between these stones, which have nearly identical physical and chemical properties, need to be examined by a jewelry expert or diamond expert. Experts examine the emissions of precious stones under ultraviolet light sources to identify them. These procedures, conducted with human observation, are both costly and time-consuming.

[0008] In the appraisal of jewelry stones, test devices are needed to ensure the trust of industry workers and buyers. Identifying precious stones with test devices is an important advantage as it is less costly and requires less expertise. WO2021 140128A1 discloses a method for irradiating a precious stone largely with ultraviolet radiation pulses at wavelengths of 225 nm or lower, capturing the luminescence emitted by the top and bottom parts of the stone, comparing these characteristics, and characterizing the composition of the precious stone based on this comparison.

[0009] BRIEF DESCRIPTION OF THE INVENTION

[0010] The object of this invention is to provide a method for identifying precious stones, rings, bracelets, or other valuable objects of different shapes by examining them to distinguish between natural stones and those manufactured in a laboratory, and / or to determine the quality and physical properties of the stone.

[0011] One objective of the invention is to provide a method for identifying precious stones that requires less technical expertise, is fast, and has a high degree of accuracy.

[0012] In order to achieve above objectives, the invention is an identification method for a test device comprising a body into which the precious stones are placed, and a movable tray to carry the stones to be examined inside the body; at least one UVC light source used for illuminating the stones; and at least one UVA light source used to enhance the accuracy of identifying the precious stones; at least one camera installed in the body captures images of the stones, and at least one control unit processes data from these images and at least one screen connected via a network connection for data transmission from a control unit. The method comprises the steps of capturing at least one image under a light source with a 222 nm UVC wavelength through a camera at different lens apertures and selecting the most accurate image to be sent to a control unit; the control unit runs an image processing algorithm to examine the fluorescence and phosphorescence emissions of the precious stones; capturing images under a light source with a 365 nm UVA wavelength by a camera at different lens apertures and sent to the control unit to increase the accuracy of the data; runs an image processing algorithm by the control unit to examine the fluorescence and phosphorescence emissions; the accuracy of identifying precious stones is enhanced by adjusting the sensitivity setting defined in the image processing algorithm. In this case, by controlling the adapted 365 nm UV LED, the accuracy of the image processing algorithm is enhanced, allowing for the most accurate identification as requested. Moreover, using different lens apertures to increase the accuracy rate provides users with the freedom to select the most accurate visual.

[0013] In a preferred application of the invention, the sensitivity setting defined in the image processing algorithm is a value between 0 - 255. This allows the user to fine tuning the diagnosis of the stones that do not shine fully due to their characteristics but create suspicion.

[0014] In another preferred embodiment, the wavelengths of the light sources used for identifying precious stones or objects of different shapes are constant and a camera captures an image and sends it to a control unit, which processes the image digitally using an image processing algorithm.

[0015] In another preferred application, the method comprises the steps of examining all the stones for their fluorescence and phosphorescence emissions by sequentially turning on multiple light values, examining the entirety of the precious stones under the light source, and identifying the precious stones. The analysis of each stone placed inside the body is facilitated by examining the reflections over the entirety of the stone.

[0016] In another preferred embodiment, the test device comprises four light sources each with a 222 nm UVC wavelength, at least one light source with a 365 nm UVA wavelength, and a daylight source installed on the upper wall of the body. This arrangement of light sources achieves the most accurate rate in distinguishing the stones. Synthetic diamonds, often called lab-grown, usually contain complex emission patterns. The most accurate light source placement helps eliminate situations that might cause suspicion to the user or the end consumer. Re-checking precious stones through specific wavelength light sources of 222 nm and 365 nm enhances the accuracy rate, making reliable identification possible.

[0017] In another preferred embodiment, the test device includes at least one external display connected via an interface element. This provides user convenience with the external display. In a preferred setup of the invention, the display used is a smartphone or tablet. Through the interface used with the external display, the user can easily identify and view the status of objects whose quality-affecting characteristics are specifically selected for analysis on the device.

[0018] In another preferred application, the method includes a cylindrical holder apparatus for placing objects of different shapes like rings or bracelets inside a body. To identify objects of different shapes such as necklaces, rings, and bracelets, these objects need to be dismantled. Instead, the provided cylindrical holder apparatus allows for the examination and identification of the objects without dismantling and damaging them.

[0019] In another preferred application, multiple objects of different shapes like rings or bracelets are placed on a cylindrical holder apparatus; the holder rotates at determined angles via a motor connected to the holder; a camera captures multiple images at these angles, and the images are merged to examine the entirety of the object.

[0020] In another preferred embodiment, the examining the fluorescence and phosphorescence emissions of precious stones or objects of different shapes are conducted under a daylight source and covering the inner surface of the body with an anti-reflectance coating. This ensures that the most accurate images of reflections occurring during illumination of the precious stones under the light source are obtained. This coating prevents any reflections from surfaces like the lid or body that could affect the analysis during testing.

[0021] In another preferred embodiment, a tray inside a body; moving the stones to be examined inside the body by pressing a lid located on top of the body, which causes the tray to move automatically via a rail. The tray allows multiple precious stones to be placed at once, providing a compact structure instead of complex multi-part configurations. It enables the user to place and examine multiple stones without the need for adjustments, providing precise and easy use without having to interact with the device. As described in another embodiment of the invention, the tray is automatically opened through the interface provided on the front cover of the body with the external display. In another preferred embodiment, the precious stones in question are either natural diamonds or diamonds produced in a laboratory. Diamonds are particularly the most sought-after stones in the jewelry industry. Synthetic diamonds resemble natural diamonds so closely that they are indistinguishable to the eye. Therefore, test devices that include a method for identifying precious stones are mostly used during the analysis of diamonds.

[0022] In another preferred application, the examination of precious stones results in the identification of natural diamonds, zirconium, CVD, moissanite, HPHT as the type of diamond; a certificate can be created based on the test results obtained through at least one external display connected for data transmission. Synthetic diamonds are commonly used in jewelry, and for this reason, customers request a certificate to confirm that the product they purchased is a natural diamond. Jewelers and retail locations provide an analysis and a reliable shopping opportunity with a certificate directly accessible to the final consumer.

[0023] In another preferred embodiment, the test device involved in the identification method is powered by a Type-C adapter. This provides a modern power option, achieving cost efficiency and ease of use.

[0024] BRIEF DESCRIPTION OF THE FIGURES

[0025] Figure 1 represents a test device incorporating a method for identifying precious stones.

[0026] Figure 2 shows a perspective view of a structural arrangement of a test device incorporating a method for identifying precious stones.

[0027] Figure 3 is a representative display of the light sources located on the upper wall of the test device body and the camera used for capturing images.

[0028] Figure 4 displays a flowchart related to the method of identifying precious stones.

[0029] Figure 5 shows a flowchart of the image processing algorithm. Figure 6 is a schematic representation of the UVC process used in a method for identifying precious stones.

[0030] DETAILED DESCRIPTION OF THE INVENTION

[0031] This detailed description explains the invention without any limitations and only with references to examples to better illustrate the subject matter.

[0032] In Figure 1 , a test device is shown in cross-section, capable of distinguishing diamonds through an image processing-based identification method by placing one or more precious stones, particularly diamonds, for examination.

[0033] A test device (1 ) can analyze diamonds placed on a tray (14) within a body (10) using an image processing algorithm (1 10). There is a lid (16) on the front surface of the body (10). When the lid (16) on the front wall of the body (10) is pressed, the movable tray (14) automatically extends outward. The tray (14) consists of a flat surface and can simultaneously accommodate one or more precious stones for analysis. The surface of the tray (14) is covered with an anti-reflective coating (70) to prevent reflections. The tray (14) can be manufactured from plastic, rubber, metal, or any suitable material.

[0034] Figure 2 shows a perspective view of an arrangement of the precious stone identification test device. The body (10) of the test device (1 ) is in the form of a closed box. The body (10) may be made of plastic, metal, or similar materials. Moreover, the body (10) protects components such as the control unit (50), camera (40), light sources (30, 32, 34), and motor (60) from any external factors. The inner surface and the upper wall of the body (10) are covered with an anti -reflective coating (70) to prevent reflections.

[0035] The lid (16) on the front surface of the body (10) is shown in its open state in the figure. Opposite the front wall with the lid (16) and inside the body (10), a motor (60) is positioned. This motor allows a holder apparatus (not shown) placed on it to move in determined directions, enabling the analysis of objects like rings and necklaces through a cylindrical holder apparatus.

[0036] Although not shown in the figure, a camera (40) positioned to see all the stones placed on the tray (14) under the upper wall of the body (12) that faces inside the body includes UVC (30), UVA (32), and daylight (34) light sources for illuminating the precious stones.

[0037] Figure 3 provides a schematic representation of the upper wall of the body (12) of the test device (1 ). On the upper wall (12), four UVC light sources (30) are positioned parallel to each of its corresponding four edges. Positioned on a plane parallel to the UVC light sources (30) on the right and left edges, three daylight (34) and two UVA light sources (32) are vertically arranged, making a total of five light sources. A similar arrangement has been symmetrically placed. The upper wall of the body (12) includes a 16 MP autofocus camera (40), UVC (30), UVA (32) light sources, and daylight illumination (34) devices to illuminate precious stones on the tray (14) or a cylindrical holder apparatus. The camera (40) positioned in the center of the upper wall captures images of the stones' emissions. Multiple images can be captured by the camera (40) at different lens apertures. The captured images are transmitted to the control unit (50).

[0038] Figure 4 shows a flowchart related to the method of identifying precious stones, specifying the use of different wavelength lights for analyzing the stones' emissions.

[0039] Figure 5 displays a flowchart of the image processing algorithm developed for the precious stone identification method. For instance, based on the measured range of a specified parameter, it is defined as "natural diamond" or "synthetic diamond." Based on the ranges of values obtained from the emissions, they are identified as "zirconium," "CVD," "moissanite," or "HPHT."

[0040] The image processing algorithm (110) is performed on a Raspberry Pi-based control board and outputs to an external display via HDMI (not shown in the picture). The interface created on the display allows control of the functions of the test device (1 ). The interface enables the viewing of the status information of the analyzed objects. Figure 6 provides a schematic representation of the UVC process used in the method for identifying precious stones.

[0041] REFERENCE NUMBERS

[0042] 1 Test Device

[0043] 10 Body

[0044] 12 Tray

[0045] 14 Upper Wall of the Body

[0046] 16 Lid

[0047] 30 UVC Light Source

[0048] 32 UVA Light Source

[0049] 34 Daylight Source

[0050] 40 Camera

[0051] 50 Control Unit

[0052] 60 Motor

[0053] 70 Anti-Reflective Coating

[0054] 100 Flow Chart

[0055] 110 Image Processing Algorithm

[0056] 120 UVC Process

Claims

CLAIMS1. A method for identifying precious stones using a test device (1 ) comprising a body (10) into which the stones are placed, and a movable tray (12) for carrying the stones to be examined inside the body (10); at least one UVC light source (30) used for illuminating the stones; and at least one UVA light source (32) used to increase the accuracy of precious stones identification; at least one camera (40) provided in the body (10) for capturing images of the placed stones; at least one control unit (50) for processing data from images captured by at least one camera (40); at least one screen connected through a network connection for data transmission from a control unit (50) comprising the steps of selecting the most accurate image by capturing at least one image under a light source (32) having a wavelength of 222 nm UVC through the camera (40) at different lens apertures and transmits to a control unit (50); run an image processing algorithm (1 10) with the control unit (50) to examine the fluorescence and phosphorescence emissions of precious stones, capturing images under a light source (32) with a 365 nm UVA wavelength by the camera (40) at different lens apertures, and transmitting them to the control unit (50); run an image processing algorithm (110) by the control unit (50) for examining the fluorescence and phosphorescence emissions; adjusting the sensitivity setting of the image processing algorithm (1 10) that possesses a High Dynamic Range (HDR) algorithm, which optimizes the glow colors of diamonds in overexposed images due to excessive fluorescence, to enhance the accuracy of precious stones identification.

2. A method for identifying precious stones according to claim 1 , wherein the sensitivity setting defined in the image processing algorithm (110) is a value between 0 - 255.

3. A method for identifying precious stones according to any of the preceding claims, wherein the wavelengths of the light sources used in identifying precious stones or objects of different shapes are constant and comprising steps of a transmit an image captured by a camera (40) to a control unit (50); digitalprocessing of the image transmitted by the camera (40) using an image processing algorithm (1 10) by the control unit (50).

4. A method for identifying precious stones according to claim 3, comprising the step of examining the whole of the stones to be examined for their fluorescence and phosphorescence emissions by sequentially turning on multiple light values, examining the entirety of the precious stones under the light source, and identifying the precious stones.

5. A method for identifying precious stones according to claim 4, wherein the test device comprising four light sources (30) each having a 222 nm UVC wavelength, at least one light source (32) with a 365 nm UVA wavelength, and a daylight source (34) mounted on the upper wall of the body.

6. A method for identifying precious stones according to any of the preceding claims, wherein the test device is comprising at least one external display connected to the test device (1 ) via an interface element.

7. A method for identifying precious stones according to any of the preceding claims, wherein the test device comprising a cylindrical holder apparatus for placing objects of different shapes like rings or bracelets inside the body (10).

8. A method for identifying precious stones according to claim 7, comprising the steps of placing one or more objects of different shapes like rings or bracelets on a cylindrical holder apparatus; rotating the holder at determined angles via a motor (60) connected to the holder; capturing multiple images at determined angles with a camera (40); and analyzing the entirety of the object by merging the images.

9. A method for identifying precious stones according to any of the preceding claims, comprising the step of examining the fluorescence and phosphorescence emissions of precious stones or objects of different shapes under a daylight source (34) and an anti-reflectance coating (70) covering the inner surface of the body (10).

10. A method for identifying precious stones according to any of the preceding claims, wherein a tray (12) inside a body (10); moving the stones to be examined inside the body (10) by pressing a lid (14) located on top of the body (10) which causes the tray (12) to move automatically via a rail.1 1. A method for identifying precious stones according to any of the preceding claims, wherein the precious stones are either natural diamonds or diamonds produced in a laboratory setting.

12. A method for identifying precious stones according to claim 12, comprising the steps of the identification of natural diamonds, zirconium, CVD, moissanite, HPHT as the type of the diamond; creating a certificate based on the test results obtained through at least one external display connected for data transmission.

13. A method for identifying precious stones according to any of the preceding claims, wherein the test device (1 ) involved in the identification method is powered by a Type-C adapter.

14. A method for identifying precious stones according to any of the preceding claims, comprising the step of merging collected photographs using a High Dynamic Range (HDR) algorithm to obtain more natural images.

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