Apparatus and method for capturing changes in position of at least one component mounted in assembly

Abstract

To provide an apparatus and method for capturing changes in position of at least one component mounted in an assembly.SOLUTION: An assembly is positioned in an apparatus and a camera is calibrated. An image of the assembly is recorded before the assembly is subjected to vibration. The assembly is exposed to vibration for a defined period of time and intensity. An image of the assembly is recorded after the assembly is subjected to the vibration. The two images are superposed on one another with the aid of an image processing device, and differences are identified. Results are displayed on a display, where components with changes in position (or those without changes) are highlighted visually. A user examines the results and can then take further actions on the basis of the detected changes in position.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for capturing the change in position of at least one part attached to an assembly. [Background technology]

[0002] Assemblies consisting of a large number of individual parts mounted in fixed relative positions to one another play an important role in many industrial applications. Ensuring that the individual parts maintain their fixed relative positions and stability within the assembly provides a number of important benefits.

[0003] On the other hand, the correct positioning of components is crucial for the proper functioning of the entire unit: in the automotive industry, for example, engine parts must be assembled with the utmost precision to ensure that the engine works efficiently and with maximum power, while in the electronics industry, printed circuit boards and components must be correctly positioned to ensure reliable electrical connections.

[0004] On the other hand, in many cases, especially in consumer goods and public applications, the positional integrity of parts within an assembly and the associated aesthetic quality are crucial: precise mounting and alignment make it visually appealing and give a professional impression.

[0005] For this purpose, the orientation and position of the parts in the assembly are fixed by suitable joining methods (form-fitting, force-fitting, and / or adhesive bonding). However, despite careful manufacturing and quality monitoring, defects inherent in the manufacturing process can lead to variations in the bond strength of the individual parts of an assembly. These variations can lead to undesirable changes in the position of the individual parts over the course of the assembly's service life, and eventually even to the complete detachment of individual parts from the assembly.

[0006] The impact of these defects can manifest in many ways: parts can shift or connections can become loose and come apart, causing malfunctions or even the complete destruction of the finished product. In critical applications like medical or aerospace engineering, this type of failure can have serious consequences. For example, in aesthetically important assemblies like consumer goods or architecture, loose or misaligned parts can diminish the aesthetic quality and affect the overall appearance.

[0007] As mentioned above, maintaining a consistently high level of aesthetic quality is extremely important, especially in the jewelry and watch industries, and especially in expensive luxury watches – after all, luxury watch manufacturers often use their brand and reputation as their main selling point, and the aesthetic quality of a watch is closely linked to the brand's image.

[0008] In the watchmaking industry, especially in luxury watches, diamonds and other gemstones are commonly used to enhance their appearance, prestige and value. Gems give a watch's dial, crown and case a special beauty, setting it apart from other watches. The challenge is to ensure that these gems are securely attached to the watch's case, crown and dial, and do not loosen or shift over time.

[0009] There are various techniques used to securely attach gemstones to watches, one of which is the use of prongs. The four-prong setting is a common method used in the jewellery and watch industry to secure solitaire gemstones. For example, four prongs are attached around each hole in the crown of a watch, which holds the gem securely in place while refracting light to maximize its brilliance.

[0010] The use of small diamonds of different sizes that are irregularly cut and with small facets poses additional challenges. The irregular shapes of the diamonds require fine adjustment of the prongs to ensure that the gem is held securely and will not come loose.

[0011] Watchmakers and jewelry designers must ensure that the prongs are bent evenly and tightly around the gemstones without damaging them, and that the gems are evenly distributed around the dial and crown to ensure an overall balanced and attractive look.

[0012] In the jewelry and watchmaking industries, stone setting is still often done by hand in large factory buildings by many skilled craftsmen. Gemstone setting requires a high degree of manual precision and care, but working under a microscope with powerful magnification allows craftsmen to see minute details and place the gemstones into the jewelry piece in a safe and aesthetically pleasing way.

[0013] In the manufacture of expensive luxury watches, the jewel is first set into a metal setting, then small malleable metal prongs or claws grip the jewel from different sides to hold it firmly in place. After the jewel is set into the setting, the part of the watch that holds the jewel (e.g. the crown device) is examined under a microscope. This allows the positioning of each stone to be checked very precisely. To test the strength of the setting, compressed air is aimed at the stone. This air is aimed from different directions to test the stability of the stone in the claws. If the stone moves easily or comes loose, it is marked. If the stone is found to be loose or not securely attached, the entire part of the watch (e.g. the crown device) is returned to the manufacturing process in order to re-attach the stone to the setting. The prongs are carefully loosened to open the setting, the loose stone is removed, the setting is reworked, and the stone is re-attached firmly to the setting.

[0014] Although the nail and compressed air test is a widely used and proven method for fixing gemstones in jewellery (such as watches) and testing their stability in position, it still has potential problems.

[0015] Although compressed air jets are useful as a preliminary means of testing the stability of gemstones in their metal mountings, they cannot simulate all of the everyday conditions and stresses to which jewelry may be expected to be exposed. In reality, jewelry may be subjected to a wide variety of stresses far beyond those that can be replicated by simply blowing compressed air at it. In particular, repeated shocks and vibrations can have a detrimental effect on a gemstone's stability. Stones that initially appear stable under the force of the air jet may become loose or move under these real-life conditions. Summary of the Invention [Problem to be solved by the invention]

[0016] It is therefore an object of the present invention to provide an apparatus and method for capturing changes in the position of at least one part attached to an assembly, which can preserve the desired functionality and aesthetic qualities of the assembly by simple and automated means (without the need for unavoidable manual labor). [Means for solving the problem]

[0017] This object is achieved by an apparatus for capturing the change in position of at least one part mounted in an assembly using an apparatus having the features of independent claim 1 and by a method for capturing the change in position of at least one part mounted in an assembly using the method having the features of independent claim 9.

[0018] Further advantageous modifications of the device according to the invention and the method according to the invention are given with the features of the dependent claims.

[0019] In detail, an apparatus according to the present invention for capturing a change in position of at least one part attached to an assembly includes: at least one vibration generating device for imparting a vibration motion to the assembly; at least one image capturing device for capturing images of the same partial or overall view of the assembly with the at least one part attached before and after imparting the vibration motion to the assembly; an image processing device for superimposing the images captured before and after imparting the vibration motion to the assembly; and an image reproducing device for reproducing the superimposed images together with visual highlighting of one or more parts that have or have not changed in position.

[0020] The device according to the invention uses vibration or vibrational motion to measure the change in position of a part in an assembly. In contrast to a rigidly mounted part, a loosely mounted or possibly damaged part will move due to the vibration transmitted to the assembly, resulting in a different position after the vibration load compared to before the vibration load. To perform the function of capturing such position changes, the device according to the invention is composed of several cooperating components: a vibration generator, an image capture device, an image processor, and an image reproduction device.

[0021] In accordance with the present invention, overlaying images before and after exposure to vibration can be implemented in metrology equipment and quality control to visualize and analyze misalignment or movement of parts within an assembly. Effect of the Invention

[0022] The device according to the invention can be operated as follows: first, the assembly to be inspected is placed in the device and the image capture device (e.g. a camera) is calibrated. Then, high-resolution images of the assembly are taken before the application of vibration. These serve as reference images showing the initial positions of the parts. A controlled vibration load (defined duration and intensity) is applied to the assembly. This can be done in various ways, such as mechanical excitation, vibration, or similar processes. After the vibration load, images of the assembly are captured again. These images represent the current positions of the parts after the load is applied. The images before and after the vibration load are superimposed on each other. This is done manually using image processing software or automatically using special image registration algorithms. The superimposition allows visualizing the changes in the position of the parts. Parts that have not changed position will match perfectly in the superimposition and will not show any changes. On the other hand, parts that have shifted or moved will be highlighted with a shift in the superimposition. To visualize the differences more clearly, various techniques are used, such as using color or brightness changes in the superimposed images. Highlighted areas indicate the positions of parts that have changed compared to the reference image.

[0023] This image overlay and visual highlighting makes it easier to identify potential issues or misalignments within an assembly. The technology enables fast and effective quality control, fault diagnosis and condition monitoring of assemblies in a variety of technical applications and can be useful in the automotive industry, aerospace engineering, electronics manufacturing and other sectors where precision and stability of assemblies are crucial.

[0024] The application of image processing and visual highlighting offers many advantages for the purpose of analyzing position changes within an assembly. At the same time, the quality of the captured image is important to obtain accurate results. Clear, high-resolution images minimize possible errors during image processing and increase the accuracy of position measurements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] A particularly preferred embodiment of the apparatus according to the invention further comprises a microscope, the image capture device being provided at or immediately behind the microscope eyepiece for capturing the magnified image produced by the microscope.

[0026] Incorporating a microscope into the instrument is a noteworthy addition, especially when detailed inspection of assemblies or parts requiring high magnification is important. By placing an image capture device at or just behind the microscope eyepiece, the magnified images produced by the microscope can be captured and further processed.

[0027] Integrating a microscope into the device offers various advantages. A microscope allows parts and structures to be observed under very high magnification, which is essential for analysing microstructures. The powerful magnification of a microscope allows even the slightest positional changes or misalignments within an assembly to be accurately assessed. Even the slightest orientation changes in parts and microstructures, which are barely detectable by the naked eye, can be made visible thanks to the powerful magnification. The device can be used for both macroscopic and microscopic inspections, depending on the requirements of the specific assembly or part. The recording of magnified images means that results can be documented and later analysed in detail, thereby supporting troubleshooting and process optimisation.

[0028] As a further preferred development of the aforementioned embodiment, the microscope comprises a carrier unit for assembly, which is mechanically, electrically or electromechanically coupled to the vibration generator or the vibration generator is integrated in the carrier unit.

[0029] This microscope is a special "vibration microscope" that allows to subject the assembly or sample to mechanical vibrations before, during and after the observation. This vibration excitation makes it easier to observe and analyze specific effects on or behavior of the assembly, especially when dynamic or resonance phenomena are of interest.

[0030] In the case of mechanical coupling, the carrier unit with the assembly to be tested is connected via a mechanical component to an external vibration generator. The vibration generator can be, for example, a vibration table or an electromechanical exciter that can generate precise vibrations. In the case of electrical coupling, the vibrations are excited by an electrical signal that is transmitted to the carrier unit. The carrier unit may be equipped with electromagnetic actuators or piezo elements, which generate vibrations when a voltage is applied. Electromechanical coupling is a combination of mechanical and electrical coupling. The integration of a vibration generator directly into the microscope carrier unit provides a compact and easily controllable solution for generating vibrations before, during and after observation.

[0031] Furthermore, a preferred embodiment of the apparatus according to the invention further comprises at least one illumination device for illuminating a partial or overall view of the assembly reproduced by the image capture device.

[0032] Selective illumination can highlight specific features and structures within an assembly, making positional changes easier to identify, and can improve the quality and information value of the overlaid images, thus increasing the accuracy and efficiency of positional change analysis.

[0033] Integrating a lighting device into the tool further improves the quality and accuracy of the inspection results, which is especially important when fine details or subtle changes in an assembly must be captured. The combination of vibration generator, image capture device, image processor and lighting device turns the tool into a powerful tool for analysis and quality control of position changes in assemblies and parts.

[0034] In the above-described embodiment, during the period of image overlay performed by the image processing device and reproduced by the image reproduction device, a black background is generated and the illumination by the lighting device may be adjusted such that only image areas which have undergone a change in position or have not undergone a change in position are visually highlighted as bright image areas against that background.

[0035] When superimposing images, it is highly advantageous to set the lighting system to produce a black background, in particular because it provides a clear contrast that allows the superimposed images to be more effectively visualized and clearly highlights the difference between image areas that have changed position and those that remain stable in position.

[0036] If the lighting device is adjusted to produce a black background, the image areas produced as bright image areas by the superposition performed by the image processing device are particularly clearly observed, thus highlighting in strong contrast against the black background the image areas which have changed position or which remain stable in position.

[0037] When two images are overlaid, for example, a difference image is created. This means that for each pixel in the image, the difference between the brightness (or color) values ​​of the two images is calculated. If the images match perfectly (i.e. are congruent), the difference between the two images at each pixel will be zero. If we interpret this "no difference" value as black, then a perfectly matched image will appear completely black. However, if a shift between the images is detected at some point (for example, because the position of a part has changed), that pixel will not be black, but will instead have a brightness or color value that reflects the degree of the shift.

[0038] This makes even the slightest changes easier to visually identify. Bright or colored image areas make it easier to detect misalignments or movements of parts, enabling fast and efficient quality control. At the same time, the black background provides a clear and simple representation that makes it easier to interpret the overlaid image.

[0039] Furthermore, in particularly practical embodiments of the invention, the vibration generating device is embodied as a mechanical vibrator, an electromagnetic induction vibrator, a pneumatic vibrator, a piezoelectric transducer or an electroacoustic transducer.

[0040] Each of these variants has its own characteristics and modes of operation for transmitting vibratory motion to the assembly. Mechanical oscillators generate vibrations by mechanical movement, for example via a crank or eccentric shaft. Electromagnetic induction oscillators generate vibrations by electromagnetic induction, due to the interaction of magnetic fields and electric currents. Pneumatic oscillators generate vibrations by compressed air or other gases driven by fans or pneumatic devices. Piezoelectric transducers generate vibrations by the piezoelectric effect, where a piezoelectric material undergoes mechanical deformation when a voltage is applied. Electroacoustic transducers generate vibrations by converting an electrical signal into sound waves. Appropriate variants of vibration generators can be implemented in the device depending on the specific requirements and the parts to be inspected. Regardless of the type of vibration generator, the basic operating principle of the device remains the same.

[0041] According to a further, particularly practical embodiment, the image capture device is embodied as a camera, in particular a high-resolution digital camera, which camera is in particular movable in order to set the desired image.

[0042] A movable high-resolution digital camera can be used to record the desired images of the assembly before and after the vibration motion, allowing precise detection of part position changes. The ability to move the camera allows for the flexibility of recording images from different angles, allowing for closer examination of specific areas of the assembly.

[0043] An image processor can then overlay the images recorded by the cameras, and an image playback device can play back the overlaid images, visually highlighting parts that have changed position or parts that have not changed position.

[0044] This modification allows for more accurate and comprehensive analysis of position changes within an assembly, providing an effective technique for monitoring and quality control of assemblies in a variety of applications.

[0045] According to a further preferred embodiment of the invention, the image reproduction device is embodied as a screen, in particular a high resolution display.

[0046] By using a high-resolution display, the overlaid images can be presented in high quality and detail.

[0047] An image processor overlays the images recorded before and after the vibration motion and reproduces the overlay on a high resolution display, where visual highlighting of parts that have changed position and parts that have not changed position can be clearly observed.

[0048] Using a high-resolution display as an image reproduction device allows position changes to be clearly and precisely depicted, facilitating analysis and evaluation. This is particularly important to enable precise evaluation and to detect misalignments that may cause problems with the assembly connection.

[0049] In particular, a method according to the present invention for capturing a change in position of at least one component attached to an assembly includes subjecting the assembly to a vibratory motion, recording images of the same partial or overall view of the assembly with the at least one component attached before and after subjecting the assembly to the vibratory motion, overlaying the images recorded before and after subjecting the assembly to the vibratory motion, and reproducing the overlaid images with visual highlighting of one or more components that have or have not changed in position.

[0050] The method steps of the method according to the invention described above substantially correspond to the functions of the components of the device according to the invention described above, and therefore the method according to the invention has the same advantages as those described in detail above in connection with the device according to the invention.

[0051] Therefore, the method according to the invention utilizes differential image processing or image overlay to highlight changes in part position, which is particularly useful for visualizing small or subtle assembly movements or changes.

[0052] When the overlaid images are played back, parts that have changed position and parts that have not changed position are visually highlighted. Visual highlighting makes it easy to identify affected parts, enabling quick inspection for assembly issues or misalignments.

[0053] In particular, the method according to the invention allows efficient and accurate capture of positional changes within an assembly, and can be used in a variety of applications, such as quality control, manufacturing, and engineering research, to monitor and analyze positional stability and the effects of vibrations on components.

[0054] Parts that have undergone undesired positional changes or have not undergone positional changes can be easily and clearly identified through visual highlighting in the overlaid image reproduced on the image reproduction device. In the assembly, the part is marked. The marked part is then subjected to post-processing, which depends on the application. For example, a more comprehensive inspection of the part may be performed to determine whether the positional changes are indeed significant or whether they are within acceptable tolerances. In some cases, post-processing also involves repairing or realigning the part to ensure correct positioning.

[0055] In a particularly preferred embodiment of the device or method of the invention, the assembly is a watchmaker's watch, in particular a wristwatch, more particularly a crown device for a wristwatch, and at least one part is a decorative element, in particular a piece of jewellery, more particularly a gemstone, which decorative element is held in the watchmaker's watch by a number of, in particular four, prongs.

[0056] The method of the present invention proceeds as described above, whereby a vibration is applied to the watch, and in particular its crown device, images of part or all of the watch, and in particular its crown device, before and after the vibration are applied are recorded, the images recorded before and after the vibration are superimposed to visualize a change in position of one or more decorative elements (jewels), and the superimposed images are reproduced on a high resolution display together with a visual highlighting of one or more decorative elements (jewels) which have undergone an undesirable change in position.

[0057] The corresponding decorative elements (jewels) of the watch, in particular of the crown device, are then marked and post-processed, which includes inspecting the decorative element or elements (jewels) in more detail to determine whether any changes in position are significant or fall within the acceptable tolerances. Appropriate measures are then taken, if necessary, to reposition the decorative element or elements (jewels) correctly or optionally repair or replace them, so as to maintain the quality and aesthetic appearance of the watch.

[0058] In another variant of the method according to the invention and of the device according to the invention, the assembly is an electrical or electronic assembly, in particular an assembled printed circuit board, and at least one component is an electrical or electronic component, in particular a component mounted on the surface of the printed circuit board.

[0059] The device according to the invention and the method according to the invention can therefore be applied in this alternative variant to detect and monitor undesired position changes of electrical or electronic components on an assembled printed circuit board. Depending on the requirements and functions of the printed circuit board, the surface of the printed circuit board can be provided with a large number of electrical or electronic components. These components include, for example, resistors, capacitors, diodes, transistors, integrated circuits (ICs), LEDs, crystals and oscillators, and plug-in connectors.

[0060] In this case, the device according to the invention and the method according to the invention provide an effective way for quality control and testing of positional stability in electrical or electronic assemblies, which is particularly important to ensure reliable and fault-free functioning of electrical or electronic devices. Visual highlighting allows easy identification of the components involved and facilitates targeted analysis and post-processing.

[0061] Finally, there is provided yet another variant in which the assembly is a rolling bearing and at least one part is a rolling element of the rolling bearing.

[0062] Rolling bearings are mechanical components used in many machines and mechanisms to reduce friction between moving parts and allow low-friction movement. The rolling elements that move between the inner and outer rings of the bearing are the central element of the bearing and allow low-friction movement. Depending on the type of bearing, the rolling elements can be balls, rollers, cylinders, needles, etc.

[0063] In this variant, the device according to the invention and the method according to the invention are intended to identify "blocked" rolling elements that have not undergone an accidental change of position, the movement of which is restricted by dirt, damage or other factors, which may impair the functionality and service life of the rolling bearing.

[0064] "Blocked" rolling elements are visually highlighted in the superimposed images by suitable lighting. "Blocked" rolling elements do not undergo any change in position when subjected to a vibration load and can therefore be identified by superimposing images of a rolling bearing recorded before and after the rolling bearing is subjected to vibration.

[0065] The visual highlighting of "blocked" rolling elements allows early detection of possible damage or problems in the rolling bearings, which can then be followed by targeted maintenance and / or rolling element replacement, thus improving the reliability and lifespan of the rolling bearings and avoiding machine failures.

[0066] The device according to the invention and the method according to the invention find particularly advantageous application in timepiece crown devices for luxury watches, where the outer end surface of the crown is jewelled. In luxury watches, jewels such as diamonds, sapphires or rubies are often processed into the crown device as decorative elements to give a sophisticated and luxurious aesthetic. The device according to the invention and the method according to the invention allow for accurate and efficient monitoring of the positional stability of the jewel in the crown device of the watch.

[0067] In this case, a very clear image of the jeweled crown is first recorded using a "vibration microscope" equipped with a vibration generator, a camera, an image processor and a display screen. The crown is then vigorously shaken (vibrated) by mechanical means for a few seconds. After the vibration, another image of the crown is recorded in order to record the change in the position of the jewel due to the vibration. The two recorded images (before and after the vibration) are appropriately superimposed on each other. The superimposed image is displayed on the screen of the "vibration microscope". If the superimposed images are perfectly aligned, the screen is completely black. However, if any jewel has moved due to the vibration, it will emit light in the superimposed image and be identified as the part that has moved. The moved jewel is thus visually highlighted using the "vibration microscope" and then the jewel in question is manually marked by the user in the crown device. In this way, the relevant jewel can be selectively post-processed, for example to change its position or to check further for damage. [Industrial Applicability]

[0068] The inventive device and the inventive method provide an extremely precise way to check positional changes in jewelled watch crown devices. This allows a fast and accurate assessment of the stability of jewel position, facilitating the implementation of targeted measures to maintain the aesthetic and functional quality of luxury watches. The high-resolution, high-sensitivity images of the "vibration microscope" allow detailed quality control and inspection to ensure the perfection and excellence of these high-value products.

[0069] This kind of "vibration microscope" has a wide range of potential applications, as it can generate vibration motion and has the ability to overlay images, and can be used in many fields to capture minute changes in the position of parts or blockages. In addition to the watchmaking and jewelry manufacturing industries mentioned above, other industries can also benefit from this innovative technology.

[0070] For example, a "vibration microscope" with image overlay capability can be used in the electronics industry on assembled printed circuit boards and other electronic devices to determine whether electrical and electronic components are properly attached and whether joining and soldering operations have been completed sufficiently and securely. Identifying components that are loosely fastened or poorly glued or soldered can help to avoid possible breakdowns and malfunctions.

[0071] In bearing technology, too, for rolling bearings, especially ball bearings, a "vibration microscope" with image overlay can be used to determine whether a particular rolling element (ball) is "stuck" or unable to move freely. Stuck rolling elements (balls) lead to friction, wear and reduced bearing performance. Early detection of such problems allows the rolling elements in question to be repaired or replaced in good time, ensuring the functionality of the rolling bearing (ball bearing).

[0072] The wide range of applications of the "Vibration Microscope" with image overlay function proves that it is an extremely versatile and useful technology: in various industrial applications, identifying component displacements or blockages leads to improved quality control, increased product reliability and longer life span of assemblies.

Claims

1. 1. An apparatus for capturing a change in position of at least one component attached to an assembly, comprising: at least one vibration generator for imparting a vibratory motion to said assembly; at least one image capture device for recording images of the same partial or overall view of said assembly with at least one component attached before and after subjecting said assembly to a vibrational motion; an image processor for superimposing images recorded before and after subjecting said assembly to a vibratory motion; an image reproduction device for reproducing the superimposed image together with visual highlighting of one or more parts that have or have not changed position; 13. An apparatus comprising:

2. 10. The apparatus of claim 1, further comprising a microscope, wherein the image capture device is provided at or immediately behind a microscope eyepiece for recording a magnified image produced by the microscope.

3. The apparatus of claim 2 , wherein the microscope comprises a carrier unit for assembly, the carrier unit being mechanically, electrically or electromechanically coupled to the vibration generator or the vibration generator being integrated into the carrier unit.

4. The apparatus of any one of claims 1 to 3, further comprising at least one illumination device for illuminating a partial or overall view of an assembly displayed by said image capture device.

5. 5. The device according to claim 4, wherein during the period of superimposition of images performed by the image processing device and reproduced by the image reproduction device, a black background is generated and illumination by the illumination device is adjusted such that only image areas which have undergone a change in position or have not undergone a change in position are visually highlighted as bright image areas against the background.

6. The device according to any one of claims 1 to 5, wherein the vibration generating device is embodied as a mechanical vibrator, an electromagnetic induction vibrator, a pneumatic vibrator, a piezoelectric transducer, or an electroacoustic transducer.

7. 2. The apparatus according to claim 1, wherein the image capture device is embodied as a camera, in particular a high resolution digital camera, which camera is in particular movable for setting a desired image.

8. 2. Apparatus according to claim 1, wherein the image reproduction device is embodied as a screen, in particular a high-resolution display.

9. 1. A method for capturing a change in position of at least one part attached to an assembly, comprising: imparting a vibratory motion to the assembly; Recording images of the same partial or overall view of the assembly with the at least one part attached before and after subjecting the assembly to a vibration movement; superimposing images recorded before and after subjecting the assembly to a vibrational motion; Reproducing the superimposed image with visual highlighting of one or more parts that have undergone a position change or have not undergone a position change; A method comprising:

10. 10. The method of claim 9, wherein at least one part visually highlighted in the reproduced superimposed image is marked within the assembly, and the at least one marked part is subjected to post processing.

11. Apparatus according to any one of claims 1 to 8 or method according to claim 9 or 10, wherein the assembly is a watchmaker's timepiece, in particular a wristwatch, more particularly a crown device for a wristwatch, and wherein the at least one part is a decorative element, in particular a piece of jewellery, more particularly a gemstone, and wherein the decorative element is held in the watchmaker's timepiece by a plurality of, in particular four, prongs.

12. Apparatus according to any one of claims 1 to 9 or method according to claim 11 or 12, wherein the assembly is an electrical or electronic assembly, in particular an assembled printed circuit board, and the at least one component is an electrical or electronic component, in particular a component mounted on the surface of the printed circuit board.

13. Apparatus according to any one of claims 1 to 9 or method according to claim 11 or 12, wherein the assembly is a rolling bearing and the at least one part is a rolling element of the rolling bearing.