KR20060122483A - Camera link transmitting/receiving apparatus using optical fiber cable - Google Patents

Abstract

A camera link transmitting/receiving apparatus using an optical fiber cable is provided to basically solve deterioration of data due to EMI(Electro Magnetic Interference) and RFI(Radio Frequency Intereference). A connector is connected to a camera(10) and receives the image data outputted from the camera according to the camera link standard. A signal conversion member converts the image data inputted through the connector into a connectable signal type through an optical cable(300). A DC(Direct Current) balance member encodes the signal converted at the signal conversion member through the scramble. A parallel/serial conversion member converts the signal outputted from the DC balance member into a serial type signal. A light emitting member converts the serial type signal into an optical signal. An optical module is connected to the optical cable so that the converted optical signal is transmitted.

Description

Camera link transmitting / receiving apparatus using optical fiber cable

1 is a block diagram showing a data transmission system using a copper cable according to the prior art

2 is a block diagram showing an apparatus for transmitting and receiving a camera link using an optical cable according to the present invention.

3 is a block diagram showing the configuration of the transmission apparatus of FIG.

4 is a block diagram showing a configuration of a receiving device of FIG.

5 is a block diagram showing a configuration of a multiple output receiver in a camera link transceiver according to the present invention.

* Explanation of symbols for main parts of the drawings

100: transmitting device

110: connector 120: signal conversion unit

130: DC balance unit 140: bottle / serial converter

150: light emitting unit 160: optical module

200: receiver

210: optical module 220: light receiving unit

230: bottle / serial conversion unit 240: DC balance unit

250: signal conversion unit 260: connector

The present invention relates to a camera link transmission and reception apparatus, and more particularly, to a camera link transmission and reception apparatus using an optical cable capable of high speed long distance transmission in data transmission between a camera and a signal processing apparatus.

In general, a line scan camera, unlike an area scan camera, has an array of charge coupled devices (CCDs), which are image sensors, in a single line, and outputs one line of image data every certain period.

Therefore, by using a line scan camera, a high resolution image can be continuously obtained line by line in a relatively fast time.

Due to this feature, it is widely used as an inspection equipment for inspecting products in production processes such as glass, film, textile fabrics, and steel.

As shown in FIG. 1, a conventional line scan camera 10 is connected to a frame grabber 20, and the camera 10 and the frame grabber 20 are '3M' or 'InterConn'. It is connected through a copper cable (copper cable) such as 30.

In this case, the camera 10 and the frame grabber 20 perform data transmission and reception through an interface according to a camera link standard.

According to this configuration, the line scan camera 10 transmits image data of the captured image to the frame grabber 20 through the copper cable 30.

In this case, the frame grabber 20 is a processing board that receives and processes the image data transmitted from the line scan camera 10, and is connected to the main system through a PCI bus for use in a general PC environment.

In conventional camera link transmission and reception, data transmission is performed between the line scan camera 10 and the frame grabber 20 by using a copper cable 30 of 26 strands as a transmission medium.

However, in the conventional camera link transmission / reception method using a copper cable, the transmission distance becomes shorter as a faster data transmission rate is required. That is, in the case of a copper cable, a longer cable length makes it difficult to transmit data over long distances.

The 40MHz driving frequency camera, which is mainly used, can transmit about 10m of image data, and the high speed camera of 80MHz driving frequency, which will be the main force in the future, has a transmission distance of only 5m.

Currently, various newly developed inspection equipment not only increases the size of the equipment itself as the size of the inspection object increases, but also the installation distance between the camera that detects the object and the system that processes the image data of the camera (that is, the frame grabber) It is getting farther away.

That is, the inspection equipment using the conventional copper cable has a lot of limitations in the transmission distance of the image data.

In addition, in the case of copper cables, electromagnetic interference (EMI) due to the induction between cables may occur, which may have an electrical effect on the peripheral system, and external noise may cause deterioration of data moving through the cable. Can be.

In order to solve this problem, even if the shield is added to the outside of the cable, it is impossible to completely block the various noises generated from the equipment, and as the transmission distance increases and the driving frequency increases, the deterioration of the transmission data due to the noise is emerging as a serious problem.

Especially in the case of LCD and PDP surface inspection equipment, the prevention of data alteration on the transmission line is very important because the deterioration of the image data transmitted and received determines the quality of the product itself, and data errors due to noise in the inspection process can cause enormous loss. It is a problem.

In addition, the conventional inspection equipment is to apply the image information of the camera to a number of systems as a way to increase the overall image processing capacity, in the conventional case must use a separate distributor to distribute the output of the camera to several systems It was possible.

Therefore, the present invention has been made to solve the above problems, an object of the present invention is to provide a camera link transmitting and receiving device that supports high-speed long-distance transmission that is impossible with the existing copper cable using an optical fiber cable.

Another object of the present invention is to efficiently solve data degradation caused by Electro Magnetic Interference (EMI) and Radio Frequency Interference (RFI) while transmitting the data over a long distance at a high speed, thereby improving the quality of the transmission signal and efficiently processing the data. To make it possible.

Still another object of the present invention is to provide image processing of a camera to a plurality of systems at the same time without a separate distributor to be distributedly processed.

In order to achieve the above object, the present invention provides a transmitting and receiving device for performing a data transmission between the camera for detecting the image of the inspection object and the system for processing the image detected by the camera, the image data detected by the camera A transmitter for receiving the input and converting the optical signal into a form of an optical signal that can be transmitted through an optical cable; In addition, the camera link transmitting and receiving apparatus using an optical cable, which is connected to a transmitting apparatus through an optical cable, receives an optical signal transmitted from the transmitting apparatus and converts the image into electrical image data that can be processed by the system. To provide.

Here, the transmission device is a signal conversion unit for converting the image data output from the camera according to the camera link (camera link) standard in the form of a signal that can be transmitted through an optical cable, and the signal converted by the signal conversion unit scrambled ( A DC balance unit for encoding through a Scramble, a parallel / serial converter for converting a signal output from the DC balance unit into a serial signal, and a serial signal converted by the parallel / serial converter And an optical module connected to an optical cable so as to transmit a light signal converted by the light emitting unit and the light signal converted by the light emitting unit.

In this case, the light emitting unit preferably uses a vertical cavity surface emitting laser (VCSEL).

The receiving device receives an optical module connected to an optical cable to receive an optical signal transmitted from the transmitting device, an optical signal transmitted from the transmitting device through the optical module, and receives the received optical signal. De-scrambled (de-scrambled) a light receiving unit for outputting an electrical signal, a parallel / serial conversion unit for converting a signal input through the light receiving unit into a parallel signal, and a parallel signal converted by the parallel / serial conversion unit and a signal converter for converting the signal restored through the DC balance unit into image data that can be processed by the system according to a camera link standard.

In this case, the light receiving unit preferably uses a photo diode.

In addition, the present invention provides a transmission and reception device for performing a data transmission between a camera for sensing the image of the inspection object and a plurality of systems for processing the image sensed by the camera, receiving the image data detected by the camera to receive an optical cable Transmitter for converting the optical signal form that can be transmitted through; In addition, the transmission device and the optical cable are connected and connected in parallel with a plurality of systems, the optical signal transmitted from the transmission device is received, converted into electrical image data that can be processed in the system, and the converted image data. It provides a camera link transceiver using an optical cable consisting of a receiver for copying and outputting as many as the number of the system.

Here, the receiving apparatus receives an optical module connected to an optical cable to receive the optical signal transmitted from the transmitting apparatus, an optical signal transmitted from the transmitting apparatus through the optical module, and receives the received optical signal. De-scrambled (de-scrambled) a light receiving unit for outputting an electrical signal, a parallel / serial conversion unit for converting a signal input through the light receiving unit into a parallel signal, and a parallel signal converted by the parallel / serial conversion unit and a DC balancer for restoring multiple signals at the same time by restoring the restored signals by the number of systems, and outputting the signals output from the DC balancer to the system according to the camera link standard. And a signal converting unit converting the image data into processable images.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

A preferred embodiment of a camera link transmitting and receiving apparatus using an optical cable according to the present invention will be described with reference to the accompanying drawings.

2 is a conceptual diagram illustrating a camera link transmitting and receiving apparatus using an optical cable according to the present invention. 3 is a block diagram showing the structure of a transmitter according to the present invention, and FIG. 4 is a block diagram showing the structure of a receiver according to the present invention.

The camera link transmitting and receiving device according to the present invention is characterized in that the optical cable 300 is used as a data transmission medium between the camera 10 and the system 20 without the possibility of data deterioration due to electromagnetic noise.

And, to implement the two-way optical communication using the optical cable 300; A transmission device 100 connected to the camera 10 and converting the image data of the camera 10 into an optical signal, and then transmitting or receiving a camera control signal in the form of an optical signal transmitted from the system 20, and the system 20 It is connected to the () side is provided with a receiving device 200 for converting a control signal for controlling the overall operation of the camera 10 after converting it into an optical signal or receiving image data in the form of an optical signal transmitted from the transmitting device 100 do.

Here, the transmitter 100; As shown in FIG. 3, a connector 110 connected to the camera 10 to receive image data output according to a camera link standard from the camera 10, and image data input through the connector 110. A signal converter 120 for converting the signal into a signal form that can be transmitted through the optical cable 300, a DC balance unit 130 for encoding the signal converted by the signal converter 120 through a scramble, A parallel / serial converter 140 for converting a signal output from the DC balance unit 130 into a serial signal, and a serial signal converted by the parallel / serial converter 140 into an optical signal. The light emitting unit 150 and an optical module 160 connected to the optical cable 300 to transmit the optical signal converted by the light emitting unit 150.

The transmitter 100 further includes a light receiving unit 170 for receiving various signals transmitted from the system 20, and the signal received through the light receiving unit 170 is inverse to the signal transmission process. Will be processed.

On the other hand, the receiving device 200; As shown in FIG. 4, an optical module 210 connected to an optical cable 300 to receive an optical signal transmitted from the transmitter 100, and a transmitter 100 through the optical module 210. A light receiving unit 220 for receiving an optical signal transmitted from the light emitting unit, and outputting the received optical signal as an electrical signal, and converting a signal input through the light receiving unit 220 into a parallel signal. A DC balancer 240 for recovering the parallel-type signal converted by the parallel / serial converter 230 through de-scramble, and the DC balancer 240. A signal converter 250 for converting a signal reconstructed through the signal into image data that can be processed by the system 20 according to a camera link standard, and an image converted by the signal converter 250 in connection with the system 20. And a connector 260 for outputting data to the system 20.

In addition, the receiving apparatus 200 further includes a light emitting unit 270 for transmitting various control signals to be transmitted from the system 20 to the camera 10, and transmitting through the light emitting unit 270. The signal to be processed is processed in the reverse of the signal receiving process.

At this time, the light emitting units 150 and 270 applied to the transmitting apparatus 100 and the receiving apparatus 200 of the present invention generally use a laser diode, but the VCSEL emits light from the diode surface for long distance communication. It is preferable to use a vertical cavity surface emitting laser.

In addition, the light receiving units 170 and 220 may receive an optical signal transmitted from the transmitter 100 through the optical cable 300 as an input to an optical limiting amplifier receiver that outputs an electrical signal corresponding to the optical signal. It corresponds, and it is preferable that it is comprised by a photo diode.

The operation of the camera link transceiver according to the present invention configured as described above will be described in detail with reference to FIGS. 3 and 4 as follows.

First, the system 20 including a camera 10 for detecting an inspection object and a frame grabber for processing image data output from the camera 10 performs data transmission / reception according to a camera link standard. .

In general, a camera link standard may include a separate RS-232 line (serial to camera (SerTC), serial to frame grabber (SerTFG)), and a camera 10 to exchange information between the camera 10 and the system 20. 4 control lines (CC1 to CC4) (camera commands) for transmitting control commands of the system 20 and signal lines (7-bit) for transferring image data of the camera 10 to the system 20. serialized LVDS signals)

That is, the present invention is composed of an RS-232 line, a control line and a signal line according to the camera link standard to enable bidirectional optical transmission between the transmitter 100 and the receiver 200 as shown.

In addition, the data transmitted and received between the camera 10 and the system 20 has a low voltage differential signal (LVDS) signal type according to a camera link standard.

Hereinafter, a process of transmitting image data between the camera 10 and the system 20 will be described in detail.

First, the camera 10 basically converts image data to be transmitted to the system 20 into an LVDS digital signal and outputs the converted image data.

In this case, the LVDS signal output from the camera 10 is input to the transmitter 100 through the connector 110.

The LVDS signal thus input is converted into a TTL / LVTTL signal suitable for implementing a DC balance function and output.

In this case, the signal converter 120 has 8 bits of image data R, G, and B, and 1 bit of horizontal sync signal (HSYNC), vertical sync signal (VSYNC), DE (data enable), and clock (CLK), respectively. A total of 28 bits of TTL / LVTTL signal are output.

Subsequently, the DC balance unit 130 encodes or encrypts the signal converted into the TTL / LVTTL signal by the signal converter 120 through scramble and outputs the encoded signal.

In order to convert the image data of the camera 10 into an optical signal, a DC balance function is essential. The DC balance unit 130 checks the signal state of each data line and deforms each signal line so as to maintain the DC balance, and then, the receiver 200 restores the signal to the original form. Will be sent together.

The encoded or encrypted TTL / LVTTL signal is formed in the form of parallel data. The parallel / serial converter 140 converts the TTL / LVTTL signal into serial data and outputs the serial data.

The present invention serializes a plurality of parallel data in order to transmit the image data of the camera 10 over a long distance and to use a minimum transmission line.

For example, the bottle / serial converter 140 may apply an 18: 1 serialize method.

As such, the data converted into a serial signal through the parallel / serial converter 140 is converted into an optical signal that can be transmitted to the receiver 200 through the optical cable 300 via the light emitting unit 150.

The optical signal converted by the light emitting unit 150 is transmitted to the receiver 200 along the optical cable 300 via the optical module 160.

On the other hand, the receiving device 200 receives the optical signal transmitted from the transmitting device 100 through the optical module 210 connected to the optical cable 300.

Thereafter, the light receiving unit 220 of the receiver 200 inputs an optical signal received through the optical module 210 and outputs electrical data corresponding to the intensity of the input optical signal.

In addition, the data output in the serial form from the light receiving unit 220 is transferred to the parallel / serial converter 230 to convert the parallel data, the parallel / serial converter 140 of the transmitter 100 Corresponds to the 1:18 parallel transform scheme.

At this time, the DC balance unit 240 is a data form that was transmitted in parallel from the parallel / serial converter 230 in the form of data transmitted from the transmitter 100 through the de-scramble (de-scramble) TTL / LVTTL Restore to the signal.

The TTL / LVTTL signal restored by the DC balance unit 240 is converted into an LVDS format signal according to a digital transmission method through the signal converter 250 and then output.

Subsequently, the LVDS signal output from the signal converter 250 is transmitted to the system 20 connected through the connector 260.

Thereafter, the system 20 performs signal processing on the image data transmitted from the camera 10 through a transmission / reception interface using the optical cable 300.

On the other hand, the transmission and reception of the RS-232 signals (SerTC, SerTFG) and control signals (CC1 ~ CC4) between the camera 10 and the system 20 is made in the same manner as the signal processing process of the image data described above and a detailed description thereof Will be omitted.

Furthermore, in the present invention, when there is a limitation in processing an image of the camera 10 into a single system, two or more systems may be connected in parallel according to the amount of data output from the camera 10. The image will be distributed.

In this case, in order to deliver the same image to multiple systems, the receiver 200 is designed to output multiple image data.

In the present embodiment, the DC balance unit 240 of the receiving device 200 is implemented using a field programmable gate array (FPGA). The descrambled copy of the original signal recovered in the TTL / LVTTL form by the number of systems is performed. After that, the same image data is designed to be multi-outputted.

In other words, the DC balance unit 240 simultaneously performs an optical converter function and a data divider function.

To this end, as shown in FIG. 5, in the same configuration of FIGS. 3 and 4, a system 20 ′ to be added for image dispersion processing is connected in parallel to the DC balance unit 240 of the receiver 200.

The added system 20 'includes a signal converter 250' and a connector 260 'in a one-to-one manner, and are connected to the output port of the DC balance unit 240.

According to this configuration, the DC balance unit 240 of the receiving device 200 restores the image data transmitted from the camera 10, and then copies the restored image data by the number of systems 20 and 20 'at the same time. Output

In this case, each system 20 and 20 ′ receives the same image data output from the DC balance unit 240 and processes each image.

Therefore, the present invention transmits data between the camera 10 and the system 20 by using the optical cable 300 as a transmission medium, and the optical cable 300 to transmit data between the camera 10 and the system 20. Provides a transmit / receive interface using.

In addition, the DC balance unit 240 at the receiver 200 may perform a data distribution function to implement an image distribution processing system without a separate divider.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

The camera link transmitting and receiving apparatus using the optical cable according to the present invention as described above has the following advantages.

First, data transmission between a camera and a system for processing image data is realized through an interface using an optical cable, thereby enabling long distance data transmission. In the case of using the existing copper cable can be transmitted up to 500m by using an optical cable that can transmit 5 to 10m.

Second, by using the optical cable to fundamentally solve the data corruption problem caused by electromagnetic noise to ensure the signal characteristics on the transmission line. That is, since it is not affected by electromagnetic noise at all, the system reliability in terms of data transmission is improved, and the processing performance of the inspection equipment can be improved by more accurate data processing.

Third, by distributing image data through multiple systems by outputting multiple image data without a separate divider, it is possible to maximize image processing capability by implementing a simpler system.

Claims (8)

In the transmitting and receiving device for performing data transmission between the camera for detecting the image of the inspection object and the system for processing the image detected by the camera, A transmitter for receiving the image data sensed by the camera and converting the image data into an optical signal that can be transmitted through an optical cable; And, A camera using an optical cable, which is connected to a transmitting device through an optical cable, and receives and receives an optical signal transmitted from the transmitting device and converts the image into electrical image data that can be processed by the system. Link transceiver. The method of claim 1, The transmitter is A signal converter for converting image data output from the camera according to a camera link standard into a signal form that can be transmitted through an optical cable; A DC balancer which encodes the signal converted by the signal converter through scramble; A parallel / serial conversion unit for converting the signal output from the DC balance unit into a serial signal; A light emitting unit converting the serial signal converted by the parallel / serial conversion unit into an optical signal; And an optical module connected to an optical cable to transmit the optical signal converted by the light emitting unit. The method of claim 2, The light emitting unit Camera link transceiver using an optical cable, characterized in that using VCSEL (vertical cavity surface emitting laser). The method of claim 1, The receiving device An optical module connected to an optical cable to receive an optical signal transmitted from the transmitter; A light receiving unit which receives an optical signal transmitted from the transmitter through the optical module and outputs the received optical signal as an electrical signal; A parallel / serial converter converting the signal input through the light receiver into a parallel signal; A DC balance unit for restoring the parallel-type signal converted by the parallel / serial converter through de-scramble; And a signal converting unit converting the signal restored through the DC balance unit into image data that can be processed by the system according to a camera link standard. The method of claim 4, wherein The light receiving unit is a camera link transceiver using an optical cable, characterized in that using a photo diode (photo diode). In the transmitting and receiving device for performing data transmission between the camera for sensing the image of the inspection object and a plurality of systems for processing the image detected by the camera, A transmitter for receiving the image data sensed by the camera and converting the image data into an optical signal that can be transmitted through an optical cable; And, It is connected to the transmitter and the optical cable and connected in parallel with a plurality of systems, after receiving the optical signal transmitted from the transmitter, converts the electrical image data that can be processed in the system and converts the converted image data Camera link transceiver using an optical cable, characterized in that consisting of a receiver for copying and outputting the number of systems. The method of claim 6, The transmitter is A signal converter for converting image data output from the camera according to a camera link standard into a signal form that can be transmitted through an optical cable; A DC balancer which encodes the signal converted by the signal converter through scramble; A parallel / serial conversion unit for converting the signal output from the DC balance unit into a serial signal; A light emitting unit by converting a serial signal converted by the parallel / serial conversion unit into an optical signal; And an optical module connected to an optical cable to transmit the optical signal converted by the light emitting unit. The method of claim 6, The receiving device An optical module connected to an optical cable to receive an optical signal transmitted from the transmitter; A light receiving unit which receives an optical signal transmitted from the transmitter through the optical module and outputs the received optical signal as an electrical signal; A parallel / serial converter converting the signal input through the light receiver into a parallel signal; A DC balance unit for restoring the parallel-type signal converted by the parallel / serial conversion unit through de-scramble and copying the restored signal as many as the number of systems and simultaneously outputting multiple signals; And a signal converter configured to convert the signal output from the DC balance unit into image data that can be processed by the system according to a camera link standard.

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