Device for surface analysis of stones and system for manufacturing stones

Abstract

The present invention discloses a device (1) for surface analysis of at least one stone (S), wherein the device (1) comprises a transport support (10) for placing and transporting at least one stone (S) in a transport direction (T), at least one 3D area scanner (20) configured to determine a topography of at least one surface (SO) of the stone (S), at least one white light line illumination device (31, 32) for emitting linear white light in the direction of the transport support (10), an RGB camera (50) for detecting light emitted by the white light line illumination device (31, 32) and reflected by the at least one surface (SO) of the at least one stone (S), and a control device (60) that is data-coupled with the at least one 3D area scanner (20) and with the RGB camera (50), wherein the control device (60) is configured toto receive topography data representing the topography of at least one surface (SO) of at least one stone (S) from the 3D surface scanner (20) and reflection data representing the reflectance of at least one surface (SO) of the stone (S) from the RGB camera (50), and to determine a height difference of the topography of at least one surface (SO) of the stone (S) based on the topography data and to output an error signal if the height difference is greater than a maximum height difference, and to determine a reflectivity of at least one surface (SO) of the stone (S) based on the reflection data and to output an error signal if the reflectivity is outside a predetermined reflectivity range.

Description

[0001] The present invention relates to a device for surface analysis of stones. Furthermore, the present invention relates to a system for manufacturing stones.

[0002] During the production of stones, especially concrete blocks such as paving stones, hollow blocks, kerbstones, and the like, the stones may have defects. These defects can include cracks, segregation, edge breaks, or even color variations on the stone's surface.

[0003] Quality control of concrete blocks produced, for example, using a stone-making machine, is currently carried out primarily by people who subjectively assess whether the manufactured blocks meet the quality requirements. If a defective block is identified, it is manually removed from a conveyor belt.

[0004] The present invention is based on the objective of providing a device for surface analysis of at least one concrete block, which enables objective, fast and more accurate quality assurance of manufactured blocks, in particular concrete blocks.

[0005] The problem underlying the present invention is solved by a device for surface analysis of at least one stone having the features of claim 1. Advantageous embodiments of the device are described in the dependent claims.

[0006] More precisely, the problem underlying the present invention is solved by a device for surface analysis of at least one stone, wherein the device has a transport platform for placing and transporting at least one stone in a transport direction, the transport platform extending in the transport direction and in a transverse direction. The device further comprises at least one 3D surface scanner configured to determine the topography of at least one surface of the stone, the 3D surface scanner being spaced vertically perpendicular to the transport direction and in a transverse direction from the transport platform.Furthermore, the device comprises at least one white light linear illumination device for emitting linear white light in the direction of the transport platform, wherein a longitudinal extension of the linear white light is oriented substantially parallel to the transverse direction of the transport platform, and wherein the white light linear illumination device is spaced vertically from the transport platform. The device also comprises an RGB camera for detecting light emitted by the white light linear illumination device and reflected from the at least one surface of the at least one stone, wherein the RGB camera is spaced vertically from the transport platform and spaced in the transport direction from the 3D area scanner.The device comprises a control unit that is data-coupled to the at least one 3D area scanner and to the RGB camera, wherein the control unit is configured to receive topography data representing the topography of the at least one surface of the at least one stone from the 3D area scanner and reflection data representing the reflectance of the at least one surface of the stone from the RGB camera, and to determine a height difference of the topography of the at least one surface of the at least one stone based on the topography data and to output an error signal if the height difference is greater than a maximum height difference, and to determine a reflectivity of the at least one surface of the stone based on the reflection data and to output an error signal if the reflectivity is outside a predetermined reflectivity range.

[0007] The device according to the invention enables objective, fast, and more precise quality assurance of manufactured stones, particularly concrete blocks. The device allows for the determination of the surface topography of at least one stone and also the determination of the color or color gradient of the surface of at least one stone. Thus, structural defects and color defects in the stone surface can be reliably identified.

[0008] The surface of the at least one stone includes, for example, a top surface and / or one or more side surfaces and / or edges of the at least one stone.

[0009] The transport platform can be designed as a conveyor belt. The transport platform is driven by a drive unit. The transport direction and the transverse direction preferably define a plane that is horizontally oriented in the installed position of the device. The transport platform can be part of a stone processing machine. Preferably, the transport platform is designed to accommodate a plurality of stones, which can preferably be positioned in several ordered rows on the transport platform.

[0010] The 3D area scanner can be configured to emit a structured light pattern in the direction of the transport platform. Based on the light pattern detected by the 3D area scanner on the surface of at least one stone, its topography can be determined, since the emitted light pattern is known.

[0011] The topography of a stone's surface refers to its surface structure. The device is preferably designed to determine the surface structure of a stone with an accuracy of up to 0.1 mm.

[0012] The at least one white light linear lighting device is preferably designed as an LED white light linear lighting device comprising a plurality of white light emitting LEDs arranged along a longitudinal extent of the white light linear lighting device.

[0013] The RGB camera features a CCD sensor. The CCD sensor is preferably designed as a CCD line sensor.

[0014] The control unit is designed as an electronic control unit. It is configured to receive data from the 3D area scanner and / or the RGB camera and / or to transmit data, in particular control signals, to them. Furthermore, the control unit is preferably data-coupled with the at least one white light line illumination device for transmitting control signals.

[0015] The reflectivity or reflectivity of the at least one surface is calculated based on the known color and emission characteristics of the at least one white light line illumination device and the reflection data received by the RGB camera.

[0016] Preferably, the device is designed such that it comprises a first white light linear illumination device and a second white light linear illumination device, each of which is signal-coupled to the control device, wherein the first white light linear illumination device and the second white light linear illumination device have a first horizontal distance from each other in the transport direction. A first emission direction of the first white light linear illumination device forms a first angle with the vertical direction, and a second emission direction of the second white light linear illumination device forms a second angle with the vertical direction.The first horizontal distance, the first angle, and the second angle are set such that the first linear white light emitted by the first white light linear illumination device and the second linear white light emitted by the second white light linear illumination device coincide on a surface of the stone.

[0017] The specially designed device enables an even more precise determination of the reflectivity of at least one surface of the stone. This is because the linear white light, directed onto the stone's surface at the first and second angles, allows shadows cast by the stone's surface topography to be factored out. This avoids false error signals.

[0018] Preferably, the magnitudes of the first angle and the second angle are equal. For example, the first angle is 35° and the second angle is -35°.

[0019] Preferably, the magnitude of the first angle and the second angle lies between 20° and 60°, more preferably between 25° and 50°, and even more preferably between 30° and 40°.

[0020] Preferably, the first white light linear lighting device and the second white light linear lighting device have the same vertical distance to the transport support. Furthermore, preferably, the first white light linear lighting device and the second white light linear lighting device are arranged symmetrically to each other with respect to a plane of symmetry spanned by the vertical and transverse directions.

[0021] Preferably, the distance of the RGB camera to the transport support, running parallel to the vertical direction, is greater than the distance of the first white light line illumination device and / or the second white light line illumination device to the transport support, running parallel to the vertical direction.

[0022] Preferably, the distance between the RGB camera and the transport support, running parallel to the vertical direction, is between 500 mm and 1500 mm, more preferably between 700 mm and 1200 mm, and even more preferably between 800 mm and 1000 mm.

[0023] Further preferably, the distance parallel to the vertical direction between the first white light line lighting device and / or the second white light line lighting device and the transport support is between 150 mm and 500 mm, more preferably between 150 mm and 400 mm, and even more preferably between 150 mm and 300 mm.

[0024] Preferably, the distance between the first white light line lighting device and the second white light line lighting device, running parallel to the direction of transport, is between 100 mm and 500 mm, more preferably between 150 mm and 400 mm, and even more preferably between 200 mm and 300 mm.

[0025] Preferably, the device is designed such that the RGB camera is arranged in the transport direction between the first white light line illumination device and the second white light line illumination device.

[0026] A suitably designed device has the advantage of compact dimensions. This is because the space between the first and second white light line illumination units is utilized by the RGB camera. Furthermore, by appropriately positioning the RGB camera relative to the first and second white light line illumination units, a more precise determination of the reflectance of at least one surface of the stone is possible, as inaccurate reflectance measurements due to misinterpretation of topographically induced shadows are reduced. Thus, false error signals are avoided.

[0027] Furthermore, preferably the RGB camera has the same distance to the first white light line illumination device and to the second white light line illumination device in the direction of transport.

[0028] Preferably, in the device, the RGB camera is designed as an RGB line sensor, wherein a line sensor longitudinal extension of the RGB line sensor runs parallel to the first linear white light and to the second linear white light, and wherein the RGB line sensor is arranged and aligned between the first white light line illumination device and the second white light line illumination device in such a way that the surface of the stone, which is illuminated by the first linear white light and / or by the second linear white light, can be optically detected by means of the RGB line sensor.

[0029] The appropriately designed device enables the determination of the reflectivity of at least one surface of at least one stone at an increased transport speed of the stone through the transport platform. This is because, due to a reduced number of pixels to be read from the RGB line sensor, the corresponding data can be processed electronically more quickly.

[0030] Preferably, the device is designed such that the first white light line lighting device and / or the second white light line lighting device are mounted at a variable distance from the transport support.

[0031] The appropriately designed device has the advantage that stones with different heights can be analyzed. This is because, due to the variable spacing of the first and / or second white light line illumination devices, they can always be positioned with respect to the transport support in such a way that a line focus of the first and / or second white light line illumination device is always located on at least one surface of the at least one stone.

[0032] Furthermore, preferably the control device of the apparatus is designed to activate the first white light line lighting device and the second white light line lighting device at different times by transmitting control signals.

[0033] The specially designed device enables an even more precise determination of the reflectivity of at least one surface of the stone. This is because the linear white light, directed onto the stone's surface at the first and second angles, allows shadows cast by the stone's surface topography to be factored out. This avoids false error signals.

[0034] Preferably, the control device of the apparatus is configured to receive the first reflection data of the at least one surface of the stone from the RGB camera for light in a red wavelength range, and to determine a first reflectivity of the at least one surface of the stone in the red wavelength range based on the first reflection data and to output an error signal if the first reflectivity is outside a predetermined first reflectivity range.Alternatively or additionally, the control device is designed to receive the reflectivity of the second reflection data representing at least one surface of the stone from the RGB camera for light in a green wavelength range, and to determine a second reflectivity of the at least one surface of the stone in the green wavelength range based on the second reflection data and to output an error signal if the second reflectivity is outside a predetermined second reflectivity range.Alternatively or additionally, the control device is designed to receive the reflectivity of the third reflection data representing at least one surface of the stone from the RGB camera for light in a blue wavelength range, and to determine a third reflectivity of the at least one surface of the stone in the blue wavelength range based on the third reflection data and to output an error signal if the third reflectivity is outside a predetermined third reflectivity range.

[0035] The specially designed device enables a more precise determination of the color or color gradient on the surface of at least one stone. This allows for a more reliable detection of color defects in the stone surface.

[0036] Preferably, the 3D surface scanner in the device is configured to emit a structured light pattern in the direction of the transport surface, to detect the at least one surface of the at least one stone illuminated by the structured light pattern, and to calculate the topographic data of the at least one surface of the at least one stone based on the detected image data.

[0037] The appropriately designed device enables a rapid and highly precise determination of the surface topography of at least one stone. Thus, the appropriately designed device allows for a reliable determination of the stone surface topography even at high transport speeds of the transport platform and therefore of at least one stone or the majority of stones.

[0038] The device is preferably designed in such a way that it can determine the surface structure of a stone with an accuracy of up to 0.1 mm.

[0039] Preferably, the device has at least two 3D area scanners, each of which optically captures an area of ​​the transport surface, wherein the respective area areas are adjacent to each other and / or partially overlapping.

[0040] Using a suitably designed device, larger areas of the transport surface can be optically scanned. This allows for an increased throughput of stones to be analyzed.

[0041] Preferably, the device is designed such that it has a light absorption device which is arranged in the transport direction between the at least one 3D area scanner and the RGB camera and extends in the vertical direction, preferably up to the transport support.

[0042] The appropriately designed device exhibits improved accuracy in determining the topography of the surface of at least one stone and in determining the color or color gradient of the surface of at least one stone, since the light emitted by the at least one white light line illumination device is not detected by the 3D area scanner, and since the light emitted by the 3D area scanner is not detected by the RGB camera. Thus, structural defects and color defects in the stone surface can be determined even more reliably.

[0043] The light absorption device is preferably designed as a light-tight curtain.

[0044] Preferably, the control device of the apparatus is designed to correct the reflectivity of at least one surface of at least one stone, taking into account the topography data.

[0045] The specially designed device enables a more precise determination of the color or color gradient of the surface of at least one stone. This allows for a more reliable detection of color defects in the stone surface. By taking into account the determined topography of the surface of at least one stone, shadows cast by the surface irradiation with the at least one white light linear illumination device can be identified or anticipated.

[0046] Preferably, the transport support of the device is designed so that a plurality of stones can be placed on it and transported in the transport direction, wherein the control device is designed to identify, when at least one error signal is issued, the at least one stone for which the error signal was issued.

[0047] The specially designed device enables even faster quality assurance of manufactured stones, especially concrete blocks. Furthermore, it significantly simplifies the sorting process, which may be carried out by an operator of the device.

[0048] The device preferably further comprises a display device for indicating the at least one identified defective stone.

[0049] The specially designed device enables even faster quality assurance of manufactured stones, especially concrete blocks. Furthermore, it significantly simplifies the sorting process, which may be carried out by an operator of the device.

[0050] The display device is preferably designed as a monitor. Furthermore, it is possible for the display device to project an optical signal (lighting) onto the defective stone, thus further simplifying the sorting process.

[0051] The device preferably further comprises a removal device for removing the at least one identified defective stone.

[0052] The appropriately designed device has an increased degree of automation, so that the device has an increased throughput of stones to be analyzed.

[0053] The removal device is preferably designed as a robot that uses a gripper arm to remove the stones identified as defective from the transport platform.

[0054] The problem underlying the present invention is further solved by a system for producing stones, in particular concrete blocks, with the features of claim 15.

[0055] More precisely, the problem underlying the present invention is solved by a system for producing stones, in particular concrete blocks, which comprises a stone-making machine and a first surface analysis device as described above, wherein the first device is arranged on a wet side of the system. The system further comprises a second surface analysis device as described above, wherein the second device is arranged on a dry side of the system.

[0056] The wet side of the system is preferably located directly downstream of the stone processing machine, so that the still wet or moist stones can be analyzed using the first surface analysis device. The dry side of the system is a section where the stones are in a dried state. For example, the moist stones are fed to a storage and / or drying unit. In this case, the dry side of the system is located downstream of the storage and / or drying unit in the direction of stone transport. Thus, the dry stones can be analyzed using the second surface analysis device.

[0057] The appropriately trained system exhibits even improved reliability in surface analysis, as the surfaces of the stones can change again during the drying process.

[0058] Further advantages, details, and features of the invention will become apparent from the following exemplary embodiments. In particular, they show: Fig. 1: a schematic cross-sectional representation of a device according to the invention for surface analysis of at least one stone; Fig. 2: a schematic top view of the in Fig. 1. Device shown for surface analysis of at least one stone; and Fig. 3: a schematic and highly simplified representation of a system according to the invention for the production of stones.

[0059] In the following description, identical reference numerals denote identical components or identical features, so that a description of a component in relation to one figure also applies to the other figures, thus avoiding repetitive descriptions. Furthermore, individual features described in connection with one embodiment can also be used separately in other embodiments. Moreover, the methods according to the first through seventh embodiments can also be combined with one another.

[0060] Fig. Figure 1 shows a device 1 for surface analysis of at least one stone S in a cross-sectional view. Fig. 2 shows the Fig. Figure 1 shows a top view of the device 1's transport support 10. The transport support 10 is designed for placing and transporting a plurality of stones S in a transport direction T. As can be seen from the Fig. 1 and Fig. As can be seen in Figure 2, the transport support 10 extends in the transport direction T and in a transverse direction Q.

[0061] The device 1 further comprises at least one 3D area scanner 20. Fig. For clarity, only a single 3D area scanner 20 is shown in Figure 1, whereas Figure 3 shows three 3D area scanners 20 of the device 1. The 3D area scanners 20 are configured to determine a topography of the surfaces SO of the stones S. As can be seen in particular from Fig. As can be seen in Figure 1, the 3D area scanners 20 are spaced from the transport support 10 in a vertical direction V, which is oriented perpendicular to the transport direction T and to the transverse direction Q.

[0062] As is particularly evident from Fig. As can be seen in Figure 2, the respective 3D area scanners 20 are designed to optically capture each surface area 11, 12, 13 of the transport support 10. In the illustrated embodiment, a first surface area 11 is adjacent to a second surface area 12, with the first surface area 11 and the second surface area 12 partially overlapping. A third surface area 13 is arranged adjacent to the second surface area 12 and also partially overlaps with the second surface area 12.

[0063] Furthermore, the device 1 has at least one white light linear illumination device 31, 32 for emitting linear white light in the direction of the transport support 10. In the illustrated embodiment, the device 1 has a first white light linear illumination device 31 and a second white light linear illumination device 32, which are only in Fig. 1, but not in Fig. Figure 2 shows that the first white light linear lighting device 31 and the second white light linear lighting device 32 have a first horizontal distance D from each other in the transport direction T.

[0064] The white-light linear lighting devices 31, 32 are arranged and aligned such that a first emission direction 41 of the first white-light linear lighting device 31 forms a first angle α1 with the vertical direction V, and that a second emission direction 42 of the second white-light linear lighting device 32 forms a second angle α2 with the vertical direction V. The first horizontal distance D, the first angle α1, and the second angle α2 are adjusted such that the first linear white light emitted by the first white-light linear lighting device 31 and the second linear white light emitted by the second white-light linear lighting device 32 coincide on a surface SO of a stone S. The respective longitudinal extent L of the linear white light runs essentially parallel to the transverse direction Q of the transport support 10.The white light linear lighting devices 31, 32 are spaced apart in the vertical direction V to the transport support 10.

[0065] In order to enable the device 1 to be used for stones S with different height extensions, the first white light line lighting device 31 and the second white light line lighting device 32 are mounted at variable distances to the transport support 10.

[0066] The device 1 further comprises an RGB camera 50 for detecting light emitted by the white light line illumination devices 31, 32 and reflected from the surface SO of a stone S. The RGB camera 50, which in the illustrated embodiment is configured as an RGB line sensor 50, is spaced vertically V away from the transport support 10. Furthermore, the RGB camera 50 is spaced in the transport direction T away from the 3D area scanner.

[0067] Out of Fig. It is evident from Figure 1 that the device 1 further comprises a control device 60 which is located in Fig. 2 is not shown. The control unit 60 is data-coupled with the 3D area scanners 20 and the RGB camera 50. Furthermore, the control unit is signal-coupled with the first white light line lighting device 31 and with the second white light line lighting device 32. The control unit 60 can be configured to activate the first white light line lighting device 31 and the second white light line lighting device 32 at different times by transmitting control signals.

[0068] As described above, in the illustrated embodiment the RGB camera 50 is designed as an RGB line sensor 50. A longitudinal axis of the RGB line sensor 50 runs parallel to the first linear white light emitted by the first white light line illumination device 31 and to the second linear white light emitted by the second white light line illumination device 32. The RGB line sensor 50 is arranged in the transport direction T between the first white light line illumination device 31 and the second white light line illumination device 32 and is oriented such that the surface SO of the stone S, which is illuminated by the first linear white light and / or the second linear white light, can be optically detected by the RGB line sensor 50.

[0069] The control unit 60 is configured to receive topographic data representing the surface SO of the stones S from the 3D surface scanner 20. Furthermore, the control unit 60 is configured to receive reflection data representing the surface SO of the stones S from the RGB camera 50. Based on the topographic data, a height difference of the surface SO is determined for each stone S, and an error signal is output if the height difference exceeds a maximum height difference. Additionally, based on the reflection data, the reflectivity of each stone's surface SO is determined, and an error signal is output if the reflectivity is outside a predetermined reflectivity range.

[0070] At the Fig. In the embodiment of the device 1 shown in Figure 1, it has a display device 80. The control device 60 is configured to identify, upon output of an error signal, the at least one stone S for which the error signal was generated and / or output. The stone S identified as faulty is displayed on or by means of the display device 80.

[0071] As from Fig. As can be seen in Figure 1, the device 1 further comprises a light absorption device 70, which can be designed, for example, as an opaque plate or curtain. The light absorption device 70 is arranged in the transport direction T between the 3D area scanners 20 and the RGB camera 50 and extends in the vertical direction V. The light absorption device 70 absorbs light generated by the first and second white light line illumination devices 31, 32 and reflected from the surfaces SO of the stones S in the direction of the 3D area scanners 20. Furthermore, the light absorption device 70 absorbs light generated by the 3D area scanners 20 and reflected from the surfaces SO of the stones S in the direction of the RGB camera.

[0072] Fig. Figure 3 shows a system 100 for producing stones S. The system S includes a stone-making machine 110 for producing stones S. Furthermore, the system includes a first in the Fig. 1 and Fig. 2 device 1 and a second one shown in the Fig. 1 and Fig. The device 1 shown in Figure 2 is located on a wet side 120 of the system 100. In the illustrated embodiment, the wet side 120 is arranged in the transport direction T of the transport platform 10 between the stone machine 110 and a storage unit 140. The storage unit 140 can, for example, be designed as a storage rack system with several storage racks 140. The storage racks 140 can be movable and can preferably be fed to a drying device, for example, an oven for drying the stones S. The second device 1 is arranged on a dry side 130 of the system 100. The dry side 130 of the system 100 is a region of the system 100 in which the stones S are present in dried form. List of reference symbols 1 Device for surface analysis 10 transport load 11 First area (of the transport load) 12 second surface area (of the transport load) 13 third area (of the transport load) 20 3D area scanners 31 first white light linear lighting device 32 Second direction of emission (of the second white light linear lighting device) 41 First direction of emission (of the first white light linear lighting device) 42 second white light linear lighting device 50 RGB camera / RGB line sensor 60 Control unit 70 Light absorption device 80 Display setup / Monitor 100 systems for making stones 110 stone machine 120 Wet side (of the stone machine) 130 Dry side (of the stone machine) 140 Storage of the system for manufacturing stones D Horizontal distance (between first and second white light linear lighting device) L Longitudinal extent of the linear white light Q transverse direction S Stein SO surface of the stone T Transport direction V Vertical direction ZL line sensor longitudinal extension α1 first angle α2 second angle

Claims

[1] Device (1) for the surface analysis of at least one stone (S), the device (1) having the following features: - a transport support (10) for placing and transporting at least one stone (S) in a transport direction (T), wherein the transport support (10) extends in the transport direction (T) and in a transverse direction (Q); - at least one 3D surface scanner (20) which is designed to determine a topography of at least one surface (SO) of the stone (S), wherein the 3D surface scanner (20) is spaced from the transport support (10) in a vertical direction (V) perpendicular to the transport direction (T) and to the transverse direction (Q); - at least one white light linear illumination device (31, 32) for emitting linear white light in the direction of the transport support (10), wherein a longitudinal extent (L) of the linear white light is oriented substantially parallel to the transverse direction (Q) of the transport support (10), and wherein the white light linear illumination device (31, 32) is spaced apart from the transport support (10) in the vertical direction (V); - an RGB camera (50) for detecting light emitted by the white light line illumination device (31, 32) and reflected by the at least one surface (SO) of the at least one stone (S), wherein the RGB camera (50) is spaced apart in the vertical direction (V) from the transport support (10) and is arranged at a distance from the 3D surface scanner (20) in the transport direction (T); and - a control device (60) which is data-coupled to the at least one 3D surface scanner (20) and to the RGB camera (50), wherein - the control device (60) is designed to - topography data representing the topography of the at least one surface (SO) of the at least one stone (S) from the 3D surface scanner (20) and - to receive reflection data representing the reflectivity of at least one surface (SO) of the stone (S) from the RGB camera (50), and - to determine, based on the topography data, a height difference of the topography of the at least one surface (SO) of the at least one stone (S) and to output an error signal if the height difference is greater than a maximum height difference, and - to determine a reflectivity of the at least one surface (SO) of the stone (S) based on the reflection data and to output an error signal if the reflectivity is outside a predetermined reflectivity range. [2] Device (1) according to claim 1, characterized by the following features: - the device (1) has a first white light line illumination device (31) and a second white light line illumination device (32), each of which is signal-coupled to the control device (60); - the first white light line illumination device (31) and the second white light line illumination device (32) have a first horizontal distance (D) from one another in the transport direction (T); - a first emission direction (41) of the first white-light line illumination device (31) forms a first angle (α1) with the vertical direction (V), and a second emission direction (42) of the second white-light line illumination device (32) forms a second angle (α2) with the vertical direction (V); and - the first horizontal distance (D), the first angle (α1) and the second angle (α2) are set such that the first linear white light emitted by the first white light linear illumination device (31) and the second linear white light emitted by the second white light linear illumination device (32) coincide on a surface (SO) of the stone (S). [3] Device (1) according to claim 2, characterized by that the RGB camera (50) is arranged in the transport direction (T) between the first white light line illumination device (31) and the second white light line illumination device (32). [4] Device (1) according to one of claims 2 or 3, characterized by the following features: - the RGB camera (50) is designed as an RGB line sensor (50); - a line sensor longitudinal extension of the RGB line sensor (50) runs parallel to the first line-shaped white light and to the second line-shaped white light; - the RGB line sensor (50) is arranged between the first white light line illumination device (31) and the second white light line illumination device (32) and is aligned such that the surface (SO) of the stone (S) which is irradiated by the first line-shaped white light and / or by the second line-shaped white light can be optically detected by means of the RGB line sensor (50). [5] Device according to one of claims 2 to 4, characterized by that the first white light line illumination device (31) and / or the second white light line illumination device (32) are mounted at a variable distance from the transport support (10). [6] Device according to one of claims 2 to 5, characterized bythat the control device (60) is designed to activate the first white light line illumination device (31) and the second white light line illumination device (32) at different times by transmitting control signals. [7] Device according to one of the preceding claims, characterized by that the control device (60) is designed to - to receive first reflection data representing the reflectivity of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a red wavelength range, and - to determine a first reflectivity of the at least one surface (SO) of the stone (S) in the red wavelength range based on the first reflection data and to output an error signal if the first reflectivity is outside a predetermined first reflectivity range; and / or - to receive second reflection data representing the reflectivity of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a green wavelength range, and - to determine a second reflectivity of the at least one surface (SO) of the stone (S) in the green wavelength range based on the second reflection data and to output an error signal if the second reflectivity is outside a predetermined second reflectivity range; and / or - to receive third reflection data representing the reflectivity of the at least one surface (SO) of the stone (S) from the RGB camera (50) for light in a blue wavelength range, and - to determine a third reflectivity of the at least one surface (SO) of the stone (S) in the blue wavelength range based on the third reflection data and to output an error signal if the third reflectivity is outside a predetermined third reflectivity range. [8] Device according to one of the preceding claims, characterized by that the 3D area scanner (20) is designed to - to emit a structured light pattern in the direction of the transport support (10), - to detect the at least one surface (SO) of the at least one stone (S) illuminated with the structured light pattern, and - to calculate the topography data of the at least one surface (SO) of the at least one stone (S) based on the acquired image data. [9] Device according to one of the preceding claims, characterized by the following features: - the device has at least two 3D surface scanners (20), each of which optically detects a surface area (11, 12, 13) of the transport support (10); and - the respective surface areas (11, 12, 13) are adjacent to one another and / or partially overlap. [10] Device (1) according to one of the preceding claims, characterized by that the device (1) has a light absorption device (70) which is arranged in the transport direction (T) between the at least one 3D area scanner (20) and the RGB camera (50) and extends in the vertical direction (V), preferably up to the transport support (10). [11] Device (1) according to one of the preceding claims, characterized by that the control device (60) is designed to correct the reflectivity of the at least one surface (SO) of the at least one stone (S) taking into account the topography data. [12] Device (1) according to one of the preceding claims, characterized by the following features: - the transport support (10) is designed so that a plurality of stones (S) can be placed on it and can be transported in the transport direction (T); - the control device (60) is designed to identify, upon output of at least one error signal, the at least one stone (S) for which the error signal was output. [13] Device (1) according to claim 12, characterized by that the device (1) has a display device (80) for displaying the at least one identified defective stone (S). [14] Device (1) according to claim 12 or 13, characterized by that the device (1) has a removal device for removing the at least one identified defective stone (S). [15] System (100) for producing stones (S), comprising - a stone machine (110) for producing stones (S); - a first device (1) for surface analysis according to one of claims 1 to 14, wherein the first device (1) is arranged on a wet side (120) of the system (100); and - a second device (1) for surface analysis according to one of claims 1 to 14, wherein the second device (1) is arranged on a dry side (130) of the system (100).

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