Image acquisition system, control method, electronic equipment and storage medium

Abstract

The invention discloses an image acquisition system, a control method, electronic equipment and a storage medium, and relates to the field of machine vision. The system comprises: a light source; the camera is connected with the light source through a first power supply trigger cable; the first controller is not connected with the camera, is connected with the light source through a second power supply trigger cable, and is used for supplying power to the camera and the light source and sending a trigger signal to the light source; the second controller is not connected with the light source, is connected with the camera through a communication cable, and is used for sending the acquired image data to the second controller by the camera and sending a preset parameter signal to the camera by the second controller; wherein the transmission time of the trigger signal and the transmission time of the parameter signal are not overlapped; and a filter circuit is arranged in the camera interface and is used for separating different types of trigger signals in the same transmission link. On the basis of integrating the camera and the light source, the number of physical links of the first power supply trigger line is reduced, the line complexity of the system is reduced, and the reliability of the system is improved.

Description

Technical Field

[0001] This invention belongs to the field of machine vision, and particularly relates to an image acquisition system, control method, electronic device and storage medium. Background Technology

[0002] In the field of machine vision, image acquisition systems used for inspection typically consist of a camera, a light source, and an industrial control computer. The camera and light source are often separate components, requiring independent power supply, control, and data transmission (e.g., camera image data). Furthermore, in scenarios such as time-division linear scanning or multi-light source illumination, precise trigger synchronization signals need to be transmitted between the camera and the light source controller for strict time alignment between the camera and light source flashes. Within such systems, existing solutions inevitably involve the following connections: power supply between the camera and external systems, communication between the camera and external systems, triggering between the camera and external systems, synchronization between the camera and the light source, power supply between the light source and external systems, and communication between the light source and external systems. The entire system has a large number of connections and complex connection states, resulting in disadvantages such as inconvenient operation, poor resistance to electromagnetic interference, and low system reliability in practical applications.

[0003] To address the shortcomings of the existing solutions, this application proposes a camera and light source deployment and connection scheme that fully utilizes the connection between the camera and the light source to relay and forward power, trigger, and control signals, thereby simplifying system connections and improving system reliability and anti-interference capabilities. Summary of the Invention

[0004] This application discloses an image acquisition system, control method, system, device, and medium, which are used to reduce the number of connecting cables in the system and improve the reliability of the system.

[0005] To achieve the above objectives, this application proposes the following technical solutions:

[0006] In a first aspect of this application, an image acquisition system is provided, comprising:

[0007] light source;

[0008] The camera is connected to the light source via a first power trigger cable;

[0009] The first controller, not connected to the camera, is connected to the light source via a second power trigger cable. It is used to supply power to the camera and the light source, and to send trigger signals to the light source. The trigger signals are used to control the operation of the camera and the light source.

[0010] The second controller is not connected to the light source but is connected to the camera via a communication cable. It is used to send the image data acquired by the camera to the second controller and to send preset parameter signals to the camera. The parameter signals are used to set the parameter information of the camera or the light source.

[0011] Both the trigger signal and the parameter signal are transmitted between the light source and the camera through the first power trigger cable, and the transmission times of the trigger signal and the parameter signal do not overlap.

[0012] The camera is connected to the first power trigger cable via an interface equipped with a filter circuit to separate different types of trigger signals in the same transmission link.

[0013] Optionally, both the first power trigger cable and the second power trigger cable are integrated cables consisting of a power line and multiple differential lines, with each differential line forming a transmission link; the communication cable is formed by a network cable or optical fiber.

[0014] Optionally, if the camera is an area scan camera, the trigger signal is a frame trigger signal; the first power trigger cable consists of a power line and at least two differential lines; wherein, one differential line is used for the light source to send a frame trigger signal to the camera, as well as confirmation characters for the start and end of parameter signal transmission, and the other differential line is used for the camera to send a frame trigger signal, a parameter signal, and a flag signal for the start and end of parameter signal transmission to the light source.

[0015] Optionally, if the camera is a line scan camera, the trigger signal includes a line trigger signal and a frame trigger signal; the first power trigger cable consists of a power line and at least three differential lines; wherein, one differential line is used for the light source to send a confirmation character for the start and end of the transmission of the line trigger signal, the frame trigger signal, and the parameter signal to the camera, and the other two differential lines are used for the camera to send a flag signal for the start and end of the transmission of the frame trigger signal, the line trigger signal, the parameter signal, and the parameter signal to the light source;

[0016] Within the camera's interface, filtering circuits with different passband ranges are set up according to the frequencies of the line trigger signal and the frame trigger signal to separate the line trigger signal and the frame trigger signal.

[0017] Optionally, the power supply voltage sent by the first controller through the power line in the second power trigger cable is processed by the light source and then sent to the camera through the power line in the first power trigger cable to power the light source and the camera.

[0018] Optionally, after the light source receives the trigger signal, the light source sends the trigger signal to the camera and drives the camera to capture images, so that the camera's image capture frequency is synchronized with the light source's illumination frequency; or, after the light source sends the trigger signal to the camera, the camera sends the trigger signal back to the light source and drives the light source to illuminate, so that the camera's image capture frequency is synchronized with the light source's illumination frequency.

[0019] Optionally, the signal transmitted between the camera and the light source via the first power trigger cable also includes a reset signal, used to reset the settings before the light source illuminates.

[0020] In a second aspect of this application, a control method is provided, applied to the system described in any one of the first aspects, the method comprising:

[0021] After the camera receives the instruction to start transmitting parameter signals sent by the second controller, the camera generates a flag signal to start transmitting parameter signals and sends it to the light source through the first power trigger cable.

[0022] After receiving the flag signal indicating the start of parameter transmission, the light source sends an acknowledgment character indicating the start of parameter transmission to the light source via the first power trigger cable, and stops receiving and sending trigger signals.

[0023] After the camera receives the instruction to end the transmission of the parameter signal sent by the second controller, the camera generates a flag signal to end the transmission of the parameter signal and sends it to the light source through the first power trigger cable.

[0024] After receiving the flag signal indicating the end of parameter transmission, the light source sends a confirmation character indicating the end of parameter transmission to the camera via the first power trigger cable, and begins to receive and send trigger signals.

[0025] In a third aspect of this application, an electronic device is provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus.

[0026] Memory, used to store computer programs;

[0027] A processor, when executing a program stored in memory, implements the control method described in the second claim.

[0028] In a fourth aspect of this application, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a processor, the computer program implements the control method described in any of the second aspects.

[0029] The beneficial effects of this application are as follows:

[0030] This application provides an image acquisition system, comprising: a light source; a camera connected to the light source via a first power trigger cable; a first controller not connected to the camera but connected to the light source via a second power trigger cable, used to supply power to the camera and the light source, and to send a trigger signal to the light source; wherein the trigger signal is used to control the operation of the camera and the light source; and a second controller not connected to the light source but connected to the camera via a communication cable, used to send acquired image data from the camera to the second controller, and to send preset parameter signals from the second controller to the camera; wherein the parameter signals are used to set parameter information for the camera or the light source.

[0031] Both the trigger signal and the parameter signal are transmitted between the light source and the camera through the first power trigger cable, and the transmission times of the trigger signal and the parameter signal do not overlap; the interface of the camera connected to the first power trigger cable is equipped with a filter circuit to separate different types of trigger signals in the same transmission link.

[0032] Based on the above processing, this application sets a first power trigger cable between the light source and the camera for power supply and transmission of trigger signals and parameter signals. This allows the camera and light source to be integrated into one structure, reducing the number of external cables to two and improving the integration of the image acquisition system.

[0033] Meanwhile, the transmission times of the trigger signal and parameter signal within the first power trigger cable do not overlap, allowing them to be transmitted sequentially via a single transmission link. Furthermore, since the camera incorporates a filtering circuit, different types of trigger signals within the same transmission link can be separated. Therefore, different types of trigger signals in this application can also be transmitted via a single link. Based on the aforementioned processing, this application, by integrating the camera and light source, can effectively reduce the number of physical links in the first power trigger cable between the camera and the light source, reducing system circuit complexity. By reducing the number of cables, not only can the connection failure rate be reduced, but the probability of external environmental interference affecting the transmission cables in the image acquisition system can also be decreased, thereby improving system reliability. Attached Figure Description

[0034] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0035] Figure 1 This is a structural diagram of an existing image acquisition system provided in this application;

[0036] Figure 2 This is a structural diagram of an image acquisition system provided in this application;

[0037] Figure 3 This is a structural diagram of another image acquisition system provided in this application;

[0038] Figure 4 This is a schematic diagram of a differential circuit connection provided in this application;

[0039] Figure 5 This is a flowchart illustrating a control method provided in this application;

[0040] Figure 6 This is another connection diagram of a differential circuit provided in this application;

[0041] Figure 7 This is a structural diagram of an electronic device provided in this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0043] In the field of machine vision, especially in precision inspection scenarios, the triggering control and parameter configuration of the camera and light source are crucial aspects of the system's operation for any image acquisition system. Existing image acquisition system structures typically look like this: Figure 1 As shown, the camera and light source use multiple cables to independently transmit trigger signals and communication signals. This requires separate power supply cables (i.e., power lines), trigger cables for transmitting trigger signals, parameter update cables for parameter configuration (i.e., communication lines), and synchronization trigger lines, such as... Figure 1 As shown by the midline A.

[0044] In existing image acquisition systems, the physical link between the camera and the light source involves the transmission of trigger and communication signals via independent cables. In practice, due to limitations in site conditions and cable routing, the synchronization trigger line between the camera and the light source typically needs to be connected away from both. This results in longer cable lengths and higher cable losses in existing image acquisition systems, requiring higher power output from the driver. Furthermore, the long cables have high parasitic capacitance, limited transmission bandwidth, and require higher driving capabilities due to charging and discharging processes. Additionally, the large number and length of cables in existing image acquisition systems increase the likelihood of electromagnetic interference from the environment, leading to lower system stability.

[0045] To address the aforementioned problems, this application provides an image acquisition system, such as... Figure 2 As shown, the system includes:

[0046] light source.

[0047] The camera is connected to the light source via a first power trigger cable.

[0048] The first controller, which is not connected to the camera, is connected to the light source via a second power trigger cable. It is used to supply power to the camera and the light source, and to send trigger signals to the light source. The trigger signals are used to control the operation of the camera and the light source.

[0049] The second controller is not connected to the light source, but is connected to the camera via a communication cable. It is used to send the image data acquired by the camera to the second controller, and to send preset parameter signals to the camera by the second controller. The parameter signals are used to set the parameter information of the camera or the light source.

[0050] Both the trigger signal and the parameter signal are transmitted between the light source and the camera through the first power trigger cable, and the transmission times of the trigger signal and the parameter signal do not overlap.

[0051] The camera is connected to the first power trigger cable via an interface equipped with a filter circuit to separate different types of trigger signals in the same transmission link.

[0052] Based on the above processing, this application sets a first power trigger cable between the light source and the camera for power supply and transmission of trigger signals and parameter signals. This allows the camera and light source to be integrated into one structure, reducing the number of external cables to two and improving the integration of the image acquisition system.

[0053] Meanwhile, the transmission times of the trigger signal and parameter signal within the first power trigger cable do not overlap, allowing them to be transmitted sequentially via a single transmission link. Furthermore, since the camera incorporates a filtering circuit, different types of trigger signals within the same transmission link can be separated. Therefore, different types of trigger signals in this application can also be transmitted via a single link. Based on the aforementioned processing, this application, by integrating the camera and light source, can effectively reduce the number of physical links in the first power trigger cable between the camera and the light source, reducing system circuit complexity. By reducing the number of cables, not only can the connection failure rate be reduced, but the probability of external environmental interference affecting the transmission cables in the image acquisition system can also be decreased, thereby improving system reliability.

[0054] In some embodiments, the light source is used to illuminate the object under test, providing basic brightness or enhancing the contrast between the object under test and the background. In this application, the number of light sources can be one or more, and each light source consists of a light source driver and an illumination device (e.g., an LED light). The light source driver is used to drive the illumination device to emit illumination light. In this application, the camera is connected to the light source driver; in the following description, the light source can be equated with the light source driver.

[0055] In this application, the first controller is a remote control device, typically a PLC (Programmable Logic Controller) and a power supply module, which implements the functions of sending trigger signals and providing power. Figure 1 Electronic devices for remote power supply and triggering. Taking logistics inspection as an example, remote control equipment is usually used to control the entire automated production line, providing trigger signals to control the camera's image acquisition time, acquisition frequency, etc.

[0056] The second controller is typically an industrial control computer, or industrial PC, used to receive and process image information generated by the camera, and to send preset parameter signals to the camera. These parameter signals are used to set the parameters of the camera or light source; specifically, the parameter information includes the resolution of the image generated by the camera and the illuminance of the light source.

[0057] In some embodiments, both the first power trigger cable and the second power trigger cable are integrated cables composed of a power line and multiple differential cables, with each differential cable forming a transmission link; the communication cable is formed by a network cable or optical fiber, such as... Figure 3 As shown.

[0058] Specifically, in this application, only two external cables are retained after the camera and light source are integrated. The communication cable is used to transmit image data from the camera and preset parameter signals. Taking a 10 Gigabit Ethernet camera as an example, the communication cable can be a 10 Gigabit Ethernet cable or fiber optic cable. Both power trigger cables are integrated power input and trigger input cables, and can be a bundle of integrated multi-core cables, such as 6-core or 12-core cables, used to transmit the required DC power and trigger signals.

[0059] In addition, compared to existing technologies, this application eliminates the communication cable between the light source and the industrial control computer, as well as the synchronization trigger line between the light source and the camera. It is understood that since the camera and light source are directly connected via a first power trigger cable in this application, synchronous triggering can be achieved directly through signal delay, eliminating the need for an additional synchronization trigger line.

[0060] In some embodiments, the light source processes the power supply voltage sent by the first controller through the power line in the second power trigger cable, and then sends it to the camera through the power line in the first power trigger cable to power both the light source and the camera. Specifically, since the operating voltage of the light source is generally higher than that of the camera, the light source performs voltage drop processing on the received power supply voltage before sending it to the camera through the power line in the first power trigger cable.

[0061] Regarding the parameter settings for the camera and light source, during normal operation of the image acquisition system provided in this application, the camera communicates with the second controller via a communication cable to perform operations such as camera parameter configuration. Simultaneously, the camera can directly send the parameter signals for the light source from the second controller to the light source via a specific protocol or while the camera is not acquiring images, thereby enabling parameter settings for the light source.

[0062] In the image acquisition system provided in this application, both the camera and the light source can act as the dominant force to control each other. If the light source is the dominant force, after receiving the trigger signal, it sends the trigger signal to the camera and drives the camera to acquire an image, so that the camera's acquisition frequency is synchronized with the light source's illumination frequency. If the camera is the dominant force, after the light source sends the trigger signal to the camera, the camera then sends the trigger signal back to the light source and drives the light source to illuminate, so that the camera's acquisition frequency is synchronized with the light source's illumination frequency.

[0063] The following explanation uses the camera as the primary driver to illustrate the trigger sampling process. When the camera receives the trigger signal relayed by the light source, it drives the camera to capture an image and then retransmits it to the light source via the differential lines in the first power trigger cable. The light source receives the trigger signal from the camera and sequentially illuminates the zoned light sources, thus synchronizing the light source control and the camera's image capture frequency with the light source's illumination frequency.

[0064] In some embodiments, the signal transmitted between the camera and the light source via the first power trigger cable also includes a reset signal, used to reset the settings before the light source illuminates. Specifically, for an image acquisition system containing multiple light sources, a reset signal can be transmitted between the camera and the light source for synchronization operation before each illumination of multiple light sources, thereby avoiding mismatch between the camera and the light source caused by false triggering or missed triggering due to environmental interference.

[0065] In some embodiments, if the camera is an area scan camera, the trigger signal is a frame trigger signal. The first power trigger cable consists of a power line and at least two differential lines. One differential line is used for the light source to send a frame trigger signal to the camera, as well as confirmation characters for the start and end of parameter signal transmission; the other differential line is used for the camera to send a frame trigger signal, a parameter signal, and a flag signal for the start and end of parameter signal transmission to the light source.

[0066] If the camera is a line scan camera, the trigger signal includes a line trigger signal and a frame trigger signal; the first power trigger cable consists of a power line and at least three differential lines; wherein, one differential line is used for the light source to send the line trigger signal, the frame trigger signal, and the parameter signal start and end confirmation characters to the camera, and the other two differential lines are used for the camera to send the frame trigger signal, the line trigger signal, the parameter signal, and the parameter signal start and end flag signals to the light source;

[0067] Within the camera's interface, filtering circuits with different passband ranges are set up according to the frequencies of the line trigger signal and the frame trigger signal to separate the line trigger signal and the frame trigger signal.

[0068] The following uses a line scan camera and a first power trigger cable containing 6 pairs of differential lines as an example to illustrate the communication process between the camera and the light source.

[0069] The camera and light source are connected via a standard 15-pin industrial camera interface (e.g., RS485 chip), as shown in the connection diagram. Figure 4 As shown. Based on a general-purpose interface chip, it realizes the reception and driving of 3-channel differential signal input and 3-channel differential signal output. The interface circuit on the light source side is similar, realizing the input and output of 3-channel differential signals. The differential pairs of the camera and the light source drive each other. For example, the differential signal LINE4+ / - output by the camera is connected to the input port LINE1+ / - of the light source through an external connection; the differential signal LINE2+ / - input by the camera is driven by the output port LINE5+ / - of the light source through an external connection. It should be noted that... Figure 4 The above is just an example of a signal driving method; the actual data channel correspondence can be adjusted.

[0070] In the above setup, there are 6 pairs of differential lines connecting the camera and the light source at the hardware level (3 pairs of inputs and 3 pairs of outputs), and the signal distribution that needs to be transmitted between them is shown in Table 1 below.

[0071] Table 1 Differential Signal Allocation Table

[0072]

[0073]

[0074] In Table 1, encoder trigger A and encoder trigger B must be shared to generate a line trigger signal. This line trigger signal controls the timing of the line scan camera capturing the object under test; one line trigger signal controls the line scan camera's acquisition... Figure 1The frame trigger signal controls the effective time range for image acquisition by the line scan camera, determining the range of image frames. Only line trigger signals arriving within the effective time range of the frame trigger signal can serve as valid signals for controlling image acquisition by the line scan camera, thus forming the image data generated by the line scan camera. Protocol data corresponds to parameter signals, including flags indicating the start and end of parameter signal transmission. The protocol Ack represents the acknowledgment character for the start and end of parameter signal transmission.

[0075] As shown in Table 1, for a camera, a total of 4 trigger input signals (including a reset signal), 3 trigger output signals, 1 communication input (protocol Ack), and 1 communication output (protocol data) need to be transmitted, totaling 9 communication links. The required number of channels exceeds the number of physical differential lines, making direct communication impossible to allocate simply. Increasing the number of differential lines would lead to larger cable sizes and higher costs, making it unsuitable for widespread adoption.

[0076] Therefore, the image acquisition system provided in this application can set the trigger signal and the transmission signal to signals of different frequencies, so as to transmit and distinguish the trigger signal and the parameter signal in a differential line.

[0077] Specifically, the trigger signals of all differential lines use high-frequency transmission. The waveform of the trigger signal can be set to: pulse width 3.3us, period 6.6us (designed based on the highest line frequency of 150K and period of 6.67us). This setting results in a 50% duty cycle for the trigger signal, which is beneficial for achieving optimal digital filtering and shielding against environmental interference.

[0078] Secondly, the reset signal transmitted in Line 2 also uses a high-frequency coded sequence for transmission, with the same waveform pulse width of 3.3µs and period of 6.6µs. The receiving end uses the same filtering parameters. It should be noted that during image acquisition, the reset signal and the trigger signal have an inherent time sequence and will not overlap during transmission on the same differential line.

[0079] For parameter signals, low-frequency transmission is used via Line 3 and Line 4, such as a 9600 baud serial protocol. The camera and light source receivers then filter out high-frequency signals by setting a 10µs (e.g., 50µs) filtering parameter before parsing the subsequent camera-transmitted configuration data. The protocol Ack is transmitted back to the camera from the light source using the same low-frequency transmission method, and the camera uses the same 10µs filtering and parsing process.

[0080] Thus, by setting the trigger signal and parameter signal to different frequency bands, the goal of transmitting multiple signals under limited hardware connections can be achieved.

[0081] In addition, this application can also adopt a setting method in which the transmission times of the trigger signal and the parameter signal do not overlap, so as to realize the transmission of multiple signals.

[0082] Since all trigger signals must first be relayed through the light source, different operating states of the light source are set. When the light source is in protocol transmission (i.e., parameter signal transmission) state, external trigger signals are not forwarded. However, when the image acquisition system in this application starts normal image acquisition, normal external triggers are forwarded, and protocol transmission is not performed.

[0083] In this application, the protocol data transmission is configured to be executed during the camera's idle period (i.e., the state when no image is being captured). This application provides a control method, such as... Figure 5 As shown, the image acquisition system provided in this application includes the following steps:

[0084] S1. After the camera receives the instruction to start transmitting the parameter signal sent by the second controller, the camera generates a flag signal to start transmitting the parameter signal and sends it to the light source through the first power trigger cable.

[0085] S2. After receiving the flag signal indicating the start of parameter transmission, the light source sends a confirmation character for the start of parameter transmission to the light source via the first power trigger cable, and stops receiving and sending the trigger signal.

[0086] S3. After the camera receives the instruction to end the transmission of the parameter signal sent by the second controller, the camera generates a flag signal to end the transmission of the parameter signal and sends it to the light source through the first power trigger cable.

[0087] S4. After receiving the flag signal indicating the start of parameter transmission, the light source sends a confirmation character for the start of parameter transmission to the camera via the first power trigger cable, and begins receiving and sending trigger signals.

[0088] Specifically, taking Table 1 below as an example, under the normal operating state of the image acquisition system (image acquisition state), after the camera receives the instruction to start transmission of the parameter signal sent by the second controller, it sends a flag signal of protocol data (i.e., the confirmation character for starting parameter signal transmission) through Line 3. Upon receiving the flag signal, the light source immediately stops receiving and forwarding external triggers, and replies with protocol Ack (i.e., the confirmation character for starting parameter signal transmission) through Line 4. After this, the camera and light source enter an idle state where they are not acquiring images.

[0089] When the protocol transmission is complete, and the camera receives the instruction to end the transmission of the parameter signal sent by the second controller, the camera sends a special "end transmission" flag signal (i.e., the flag signal for ending the transmission of parameter signals). The light source receives the flag signal and sends Ack (i.e., the acknowledgment character for ending the transmission of parameter signals), starts receiving, and forwards the external trigger through Line4. After the camera receives the Ack, it switches the camera state to the normal image acquisition state. Thereafter, the signals transmitted by Line4 will be parsed and processed according to the trigger.

[0090] Based on the above processing, this application sets start and end flag signals for the transmission parameter signals to control the timing of data transmission and avoid conflicts between parameter signals and trigger signals.

[0091] To minimize the number of cables in the image acquisition system of this application and improve system stability, the first power trigger cable for the area scan camera consists of a power line and two differential lines. One differential line is used by the light source to send a frame trigger signal to the camera, as well as confirmation characters for the start and end of parameter signal transmission. The other differential line is used by the camera to send a frame trigger signal, parameter signal, and flag signals for the start and end of parameter signal transmission to the light source. Specifically, this application achieves normal system operation with two differential lines by eliminating the spare trigger signal cable and setting the transmission times of the trigger signal and parameter signal to not overlap, effectively reducing the number of cables, lowering the system's sensitivity to electromagnetic interference, and improving system stability.

[0092] If the camera is a line scan camera, this application can also configure the first power trigger cable to consist of a power line and three differential lines, such as... Figure 6 As shown in Table 2, one differential line, Line1, is used by the camera to send a line trigger signal, a reset flag, and protocol data (i.e., acknowledgment characters for the start and end of parameter signal transmission) to the light source. The other two differential lines, Line2, are used by the light source to send a line trigger signal A and protocol Ack (i.e., flag signals for the start and end of parameter signal transmission) to the camera, and Line3 is used by the light source to send a line trigger signal B and a frame trigger signal to the camera. Specifically, the signal transmission process of the three differential lines is shown in Table 2.

[0093] Table 2. Signal Transmission Diagram

[0094]

[0095] Among them, for the three signals transmitted on differential line 1, the aforementioned high and low frequency setting method (the trigger signal and reset signal are high frequency, and the protocol data is low frequency) can be used, or the transmission time can be non-overlapping, to ensure that the three signals are transmitted normally on the same differential line.

[0096] Similarly, for the two signals transmitted by differential line 2, the aforementioned high and low frequency settings or non-overlapping transmission times can be used for transmission.

[0097] However, for the frame trigger signal and line trigger signal transmitted in differential line 3, considering that the camera image acquisition process is often not limited to generating only one frame image, but requires the frame trigger signal and line trigger signal to be transmitted alternately, the method of non-overlapping transmission time is abandoned. Taking advantage of the different frequencies of the frame trigger signal and the line trigger signal, filter circuits with different passband ranges are set in the camera interface according to the frequencies of the line trigger signal and the frame trigger signal to separate the line trigger signal and the frame trigger signal.

[0098] Specifically, for overlapping signals transmitted from differential line 3 that include frame trigger signals and line trigger signals, this application includes a filter circuit 1 with a low-pass range of less than or equal to 200Hz (160kHz / 800 lines) within the camera interface to filter out low-frequency frame trigger signals; simultaneously, a filter circuit 2 with a high-pass range greater than 50kHz (corresponding to a period of 20µs) is included to filter out high-frequency line trigger signals. That is, the filter circuit used to filter the frame trigger signal is a low-pass filter, and its cutoff frequency needs to be less than or equal to the frequency of the frame trigger signal; the filter circuit used to filter the line trigger signal is a high-pass filter, and its cutoff frequency needs to be greater than the frequency of the line trigger signal.

[0099] The cutoff frequency in the filter circuit is calculated as follows: Where R is the resistance value of the filter resistor, and C is the capacitance value of the filter capacitor.

[0100] Based on the above settings, this application achieves reliable transmission of multiple signals on a single physical link by reasonably sharing the underlying physical link. It simplifies the image acquisition system, reduces the number of connection lines, lowers the cost of cables and connectors and the connection failure rate in the system, simplifies the wiring process, improves the system's anti-interference capability, is suitable for strong electromagnetic environments in industry, and improves the high integration and reliability of the image acquisition system.

[0101] This application also provides an electronic device, such as... Figure 7 As shown, it includes a processor 701, a communication interface 702, a memory 703, and a communication bus 704, wherein the processor 701, the communication interface 702, and the memory 703 communicate with each other through the communication bus 704.

[0102] Memory 703 is used to store computer programs;

[0103] The processor 701, when executing the program stored in the memory 703, implements any of the above control methods.

[0104] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not indicate that there is only one bus or one type of bus.

[0105] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0106] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0107] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0108] In another embodiment provided in this application, a computer-readable storage medium is also provided, which stores a computer program that, when executed by a processor, implements any of the control method steps described above.

[0109] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to perform any of the control method steps in the above embodiments.

[0110] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An image acquisition system, characterized in that, include: light source; The camera is connected to the light source via a first power trigger cable; The first controller, not connected to the camera, is connected to the light source via a second power trigger cable. It is used to supply power to the camera and the light source, and to send trigger signals to the light source. The trigger signals are used to control the operation of the camera and the light source. The second controller is not connected to the light source but is connected to the camera via a communication cable. It is used to send the image data acquired by the camera to the second controller and to send preset parameter signals to the camera. The parameter signals are used to set the parameter information of the camera or the light source. Both the trigger signal and the parameter signal are transmitted between the light source and the camera through the first power trigger cable, and the transmission times of the trigger signal and the parameter signal do not overlap. The camera is connected to the first power trigger cable via an interface equipped with a filter circuit to separate different types of trigger signals in the same transmission link.

2. The system according to claim 1, characterized in that, Both the first and second power trigger cables are integrated cables consisting of power lines and multiple differential lines, with each differential line forming a transmission link; the communication cable is formed by network cable or optical fiber.

3. The system according to claim 2, characterized in that, If the camera is an area scan camera, then the trigger signal is a frame trigger signal; the first power trigger cable consists of a power line and at least two differential lines; wherein, one differential line is used for the light source to send a frame trigger signal to the camera, as well as confirmation characters for the start and end of parameter signal transmission, and the other differential line is used for the camera to send a frame trigger signal, a parameter signal, and a flag signal for the start and end of parameter signal transmission to the light source.

4. The system according to claim 2, characterized in that, If the camera is a line scan camera, the trigger signal includes a line trigger signal and a frame trigger signal; the first power trigger cable consists of a power line and at least three differential lines; wherein, one differential line is used for the light source to send the line trigger signal, the frame trigger signal, and the parameter signal start and end confirmation characters to the camera, and the other two differential lines are used for the camera to send the frame trigger signal, the line trigger signal, the parameter signal, and the parameter signal start and end flag signals to the light source; Within the camera's interface, filtering circuits with different passband ranges are set up according to the frequencies of the line trigger signal and the frame trigger signal to separate the line trigger signal and the frame trigger signal.

5. The system according to claim 1, characterized in that, The light source processes the power supply voltage sent by the first controller through the power line in the second power trigger cable, and then sends it to the camera through the power line in the first power trigger cable to power the light source and the camera.

6. The system according to claim 1, characterized in that, After receiving the trigger signal, the light source sends the trigger signal to the camera and drives the camera to capture images, so that the camera's image capture frequency is synchronized with the light source's illumination frequency. Alternatively, after the light source sends the trigger signal to the camera, the camera sends the trigger signal back to the light source and drives the light source to illuminate, so that the camera's image acquisition frequency is synchronized with the light source's illumination frequency.

7. The system according to any one of claims 1 to 6, characterized in that, The signal transmitted between the camera and the light source via the first power trigger cable also includes a reset signal, which is used to reset the settings before the light source illuminates.

8. A control method applied to the system according to any one of claims 1-7, characterized in that, The method includes: After the camera receives the instruction to start transmitting parameter signals sent by the second controller, the camera generates a flag signal to start transmitting parameter signals and sends it to the light source through the first power trigger cable. After receiving the flag signal indicating the start of parameter transmission, the light source sends an acknowledgment character indicating the start of parameter transmission to the light source via the first power trigger cable, and stops receiving and sending trigger signals. After the camera receives the instruction to end the transmission of the parameter signal sent by the second controller, the camera generates a flag signal to end the transmission of the parameter signal and sends it to the light source through the first power trigger cable. After receiving the flag signal indicating the end of parameter transmission, the light source sends a confirmation character indicating the end of parameter transmission to the camera via the first power trigger cable, and begins to receive and send trigger signals.

9. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the control method according to any one of claims 8.

10. A computer-readable storage medium, characterized in that, A computer-readable storage medium stores a computer program that, when executed by a processor, implements the control method according to any one of claims 8.

Images