Decoding the Dot: A Deep Dive into Barcode Label Printer Electronics - Extended Section 17 |
Subtitle: Sensor Subsystem - Label Take-Up Sensor and Paper Jam Detection |
Introductory Summary |
In the previous sections, we explored sensors that detect gaps in the label media, the position of the printhead, and the presence of ribbon. But a printer faces another common and frustrating problem: paper jams. When a label gets stuck inside the printer - whether due to adhesive residue, a wrinkled ribbon, a mechanical obstruction, or simply a misfeed - the printer must detect the jam quickly and stop the motors to prevent damage to the printhead, the rollers, and the paper path. This chapter is devoted entirely to the label take-up sensor and the broader paper jam detection system. We will explain what a take-up sensor is, why it is necessary, and how it works. The take-up sensor is typically an optical or mechanical sensor that monitors the movement of the label web after it passes the printhead. If the web stops moving while the platen motor is running, the printer knows a jam has occurred. We will explore the different types of jam detection: the optical break-beam sensor, the reflective sensor, the mechanical flag sensor, and the encoder-based detection that uses the platen motor's own feedback. We will look at the signal conditioning, the time-out logic, and the integration with the motor control system. We will examine the emergency stop circuit that quickly cuts power to the motors when a jam is detected. We will look at real-world designs from major companies: Zebra's use of a high-speed optical break-beam sensor with a dedicated hardware timer for jam detection, Sato's use of a reflective sensor that detects the label movement, Brother's use of a mechanical flag sensor for simple and reliable jam detection, and Honeywell's use of the platen motor encoder to detect a stalled motor condition. We will also discuss the calibration of the sensor, the different jam scenarios, and the user notification and recovery procedures. By the end, you will understand how the printer protects itself from jams, and you will appreciate the clever engineering that turns a simple light beam into a robust jam detection system. |
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Chapter 1: The Problem - Jams Are Inevitable |
Paper jams are an unavoidable fact of life in any printer. In a barcode label printer, jams can be caused by a variety of factors: adhesive from the label sticking to the platen roller, a wrinkled ribbon that gets caught, a label that peels off the liner prematurely, a mechanical obstruction, or simply a misfeed due to worn rollers. A jam can cause the label web to stop moving, bunch up, or tear. If the printer continues to drive the platen motor when a jam has occurred, the motor may stall and overheat, the printhead may be damaged by friction, and the label web may be torn beyond repair. The printer must detect the jam quickly and stop the motors. The label take-up sensor is the primary sensor for jam detection. It monitors the movement of the label web after it passes the printhead. If the web is not moving as expected, the printer triggers a jam alert. |
Design Example: Adhesive Jam in a Food Processing Plant |
A food processing plant used label printers to print ingredient labels. The adhesive from the labels would sometimes build up on the platen roller, causing the labels to stick and jam. The printer's jam detection system would stop the motor, preventing a major jam. The operator would clean the platen roller and resume printing. Without the jam detection, the printer would have been damaged. |
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Chapter 2: The Optical Break-Beam Sensor - A Simple and Reliable Solution |
The optical break-beam sensor is a simple and reliable type of take-up sensor. It consists of an LED (light-emitting diode) on one side of the label web and a phototransistor on the other side. The LED shines a beam of light across the path of the label web. When the web is moving normally, it continuously passes through the beam, breaking the light path. The phototransistor detects the light when the web is not present. The sensor detects the movement by monitoring the interruptions. In a simple implementation, the sensor just detects the presence of the web - if the web is present, the beam is blocked; if the web is not present (e.g., it has jammed and moved out of the sensor's field of view), the beam is unblocked. However, a more sophisticated implementation uses the sensor to detect the movement by measuring the rate of interruptions - the web has perforations or edges that cause the beam to be interrupted at a rate proportional to the web speed. If the interruptions stop while the motor is running, the printer detects a jam. |
Design Example: Break-Beam Sensor in Zebra Printers |
Zebra's ZT600 series uses a high-speed optical break-beam sensor for the take-up detection. The sensor is mounted after the printhead, just before the label exits the printer. The LED is an infrared LED, and the phototransistor is a high-speed phototransistor. The sensor output is connected to a hardware timer in the CPU. The timer measures the time between the interruptions. If the time exceeds a threshold, the CPU detects a jam. The manufacturer chose the break-beam sensor because it is simple, reliable, and fast. |
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Chapter 3: The Reflective Sensor - A Non-Contact Alternative |
The reflective sensor is a non-contact sensor that can also be used for the take-up detection. The reflective sensor consists of an LED and a phototransistor on the same side of the web. The LED shines light on the web, and the phototransistor measures the reflected light. The web has a pattern - the labels have gaps, edges, or printed marks - that causes the reflected light to vary. The sensor detects the movement by measuring the variation in the reflected light. The reflective sensor is a non-contact solution, so it has no mechanical wear. However, the reflective sensor is more sensitive to the ambient light and to the media color. |
Design Example: Reflective Sensor in Sato Printers |
Sato's printer uses a reflective sensor for the take-up detection. The sensor is mounted on the top of the paper path, after the printhead. The LED shines light on the web, and the phototransistor measures the reflected light. The label's edges and gaps cause the reflected light to vary. The CPU measures the frequency of the variation. If the frequency drops to zero while the motor is running, the CPU detects a jam. The manufacturer chose the reflective sensor because it is non-contact and reliable. |
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Chapter 4: The Mechanical Flag Sensor - A Simple and Robust Solution |
The mechanical flag sensor is a simple and robust type of take-up sensor. The sensor consists of a small metal or plastic flag (a lever) that is pressed against the label web. The flag is connected to a micro-switch. When the web is moving, the flag is pushed up by the web. If the web jams and stops moving, the flag falls down due to gravity or a spring, triggering the micro-switch. The mechanical flag sensor is simple, reliable, and inexpensive. However, the flag can be affected by the dust and the debris, and it can cause a slight drag on the web. |
Design Example: Mechanical Flag in Brother Printers |
Brother's printer uses a mechanical flag sensor for the take-up detection. The flag is a small plastic lever that is pressed against the web. The flag is connected to a micro-switch. If the web stops moving, the flag falls and triggers the switch. The manufacturer chose the mechanical flag because it is simple, robust, and inexpensive. |
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Chapter 5: The Encoder-Based Detection - Using the Motor's Own Feedback |
The most sophisticated jam detection method uses the platen motor's own encoder feedback. The encoder measures the rotation of the platen motor. The CPU compares the encoder pulses to the expected movement. If the encoder pulses stop while the motor is running, the CPU detects a jam. The encoder-based detection does not require any additional sensors. It is a software solution that uses the existing encoder. The encoder-based detection is used in high-end printers that already have an encoder on the platen motor. |
Design Example: Encoder-Based Detection in Honeywell Printers |
Honeywell's printer uses the platen motor's encoder for the jam detection. The CPU monitors the encoder pulses. If the pulses stop for 50 milliseconds while the motor is running, the CPU detects a jam and stops the motor. The manufacturer chose the encoder-based detection because it does not require any additional sensors and it is very accurate. |
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Chapter 6: The Signal Conditioning - A Simple Circuit |
The take-up sensor is connected to the CPU with a simple circuit. The sensor is connected to a GPIO pin. The GPIO pin is configured as an input. A pull-up resistor is used. The CPU reads the GPIO pin and determines the state. For an optical sensor, the signal conditioning may include an amplifier and a comparator. For a mechanical flag, the signal conditioning is just a pull-up resistor. The signal conditioning is simple and reliable. |
Design Example: Signal Conditioning in Zebra Printers |
Zebra's printer uses a comparator (LM393) to condition the signal from the optical break-beam sensor. The comparator converts the analog signal to a digital signal. The digital signal is connected to a GPIO pin. The manufacturer chose the comparator because it provides a clean, noise-free signal. |
Chapter 7: The Debouncing - A Software and Hardware Solution |
The sensor signal can bounce - the mechanical flag can vibrate, and the optical sensor can be noisy. The debouncing is a technique that eliminates the bounce. The debouncing can be done in hardware (a capacitor) or in software (a timer). The software debouncing is used in most printers because it is flexible and does not require any additional hardware. |
Design Example: Software Debouncing in Sato Printers |
Sato's printer uses a software debouncing for the take-up sensor. The CPU reads the sensor and waits for the signal to be stable for 10 milliseconds. If the signal is stable, the CPU updates the state. The manufacturer chose the software debouncing because it is flexible and reliable. |
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Chapter 8: The Time-Out Logic - Detecting a Stalled Web |
The time-out logic is the core of the jam detection. The CPU measures the time between the sensor events. If the time exceeds a threshold, the CPU detects a jam. The threshold is set based on the print speed and the label size. The time-out logic is implemented in the firmware. The time-out logic is a simple but robust way to detect a jam. |
Design Example: Time-Out in Brother Printers |
Brother's printer uses a time-out logic for the jam detection. The CPU measures the time between the flag sensor events. If the time exceeds 500 milliseconds, the CPU detects a jam. The manufacturer chose the 500-millisecond threshold because it is long enough to tolerate the normal variations and short enough to detect a jam quickly. |
Chapter 9: The Emergency Stop - Cutting the Power |
When a jam is detected, the printer must stop the motors quickly. The emergency stop is a circuit that cuts the power to the motors. The emergency stop is typically a hardware circuit that turns off the motor drivers. The emergency stop is triggered by the CPU or by a hardware comparator. The emergency stop is a critical safety feature that prevents the motor from overheating and the printhead from being damaged. |
Design Example: Emergency Stop in Zebra Printers |
Zebra's printer uses a hardware emergency stop. The CPU triggers an emergency stop by pulling a dedicated enable pin low. The enable pin turns off the motor drivers. The manufacturer chose the hardware emergency stop because it is fast and reliable. The emergency stop is triggered within 1 millisecond of the jam detection. |
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Chapter 10: The Integration with the Motor Control - A Coordinated Stop |
The jam detection is integrated with the motor control system. When a jam is detected, the CPU stops the motor drivers and also turns off the printhead power. The CPU also reverses the motor for a short distance to release the jam. The integration is implemented in the firmware. The coordinated stop ensures that the printer stops safely and does not damage the paper. |
Design Example: Coordinated Stop in Honeywell Printers |
Honeywell's printer integrates the jam detection with the motor control. When a jam is detected, the CPU stops the platen motor and the ribbon motor. The CPU also turns off the printhead power. The CPU then reverses the platen motor for 5 millimeters to release the jam. The manufacturer chose the coordinated stop because it is safe and effective. |
Chapter 11: The User Notification - An Alert |
The printer must notify the user when a jam is detected. The notification is typically a message on the LCD and an audible alarm. The notification informs the user that a jam has occurred and guides the user to clear the jam. The notification is a critical part of the jam detection system. |
Design Example: LCD Message in Sato Printers |
Sato's printer displays a 'Paper Jam' message on the LCD when a jam is detected. The printer also beeps the buzzer. The manufacturer chose the LCD message because it provides a clear and detailed message to the user. |
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Chapter 12: The Jam Recovery - A Reset Procedure |
After a jam is cleared, the printer must recover. The recovery procedure is a simple reset. The user opens the cover, removes the jammed label, and closes the cover. The printer then resets the jam state and resumes printing. The recovery procedure is a simple and intuitive process. |
Design Example: Recovery in Brother Printers |
Brother's printer has a simple recovery procedure. The user opens the cover, removes the jammed label, and closes the cover. The printer then automatically resets the jam state. The manufacturer chose the simple recovery because it is easy for the user. |
Chapter 13: The Sensor's Field of View - A Mechanical Issue |
The sensor's field of view is the area that the sensor 'sees.' The field of view is determined by the optics and the sensor's placement. The field of view must be large enough to detect the web movement, but small enough to avoid false triggers. The field of view is typically 1 to 2 millimeters. The field of view is a mechanical design issue. |
Design Example: Field of View in Zebra Printers |
Zebra's printer has a field of view of 1.5 millimeters. The manufacturer chose the 1.5-millimeter field of view because it gives a good balance between the sensitivity and the noise. |
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Chapter 14: The Sensor's Position - A Mechanical Alignment |
The sensor's position is critical. The sensor must be aligned with the web's path. The sensor is typically mounted on a movable bracket that allows the user to adjust the position. The sensor's position is adjusted during the calibration. The sensor's position must be stable - any movement will cause the sensor to miss the web. |
Design Example: Sensor Position in Honeywell Printers |
Honeywell's printer has a fixed sensor position. The sensor is mounted on a rigid bracket. The manufacturer reports that the fixed position is accurate enough for the printer's requirements. |
Chapter 15: The Sensor's Response Time - A Speed Issue |
The sensor must respond quickly to the changes in the web movement. The response time is the time it takes for the sensor's output to change. The response time is determined by the phototransistor's rise time and the amplifier's bandwidth. The response time must be fast enough to detect the jam at the maximum print speed. The response time is typically 1 to 5 milliseconds. |
Design Example: Response Time in Sato Printers |
Sato's printer has a response time of 1 millisecond. The manufacturer measured the response time by using a fast oscilloscope. The manufacturer found that the response time is fast enough for the printer's speed. |
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Chapter 16: The Noise Filtering - A Clean Signal |
The sensor signal can be noisy. The noise is caused by the ambient light, the electrical interference, and the mechanical vibration. The noise must be filtered to prevent false triggers. The noise filtering is done by the low-pass filter in the amplifier and by the software averaging. The software averaging is a simple technique that averages the last N samples. |
Design Example: Noise Filtering in Brother Printers |
Brother's printer uses a software averaging filter. The filter averages the last 10 samples. The manufacturer measured the noise and found that the averaging reduced the noise by 20 dB. |
Chapter 17: The Ambient Light Compensation - A Robust Design |
The ambient light can affect the sensor. The ambient light can be sunlight, room light, or other sources. The sensor must be designed to reject the ambient light. The ambient light rejection is achieved by using an infrared LED and a phototransistor with a narrow bandpass filter. The bandpass filter passes only the LED's wavelength. The ambient light compensation is also achieved by using a differential measurement - the sensor measures the light with the LED on and with the LED off, and subtracts the two measurements. |
Design Example: Ambient Light Compensation in Zebra Printers |
Zebra's printer uses a differential measurement for the take-up sensor. The sensor measures the light with the LED on and with the LED off. The CPU subtracts the off measurement from the on measurement. The manufacturer reports that the differential measurement eliminates the effect of the ambient light. |
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Chapter 18: The Sensor's Calibration - A Factory Procedure |
The sensor is calibrated at the factory. The calibration is a simple test that checks the sensor's output. The calibration data is stored in the EEPROM. The calibration is used to set the initial state of the sensor. |
Design Example: Calibration in Honeywell Printers |
Honeywell's printer is calibrated at the factory. The technician feeds a test label and checks the sensor's output. The calibration data is stored in the EEPROM. |
Chapter 19: The Sensor's Fault Detection - A Safety Feature |
The sensor can have a fault - the signal can be stuck at a fixed level. The printer must detect the fault and take action. The fault detection is done by monitoring the sensor signal. If the signal is stuck at 0 or 5 volts for a certain period, the printer detects a fault. The printer stops the motor and displays an error message. |
Design Example: Fault Detection in Sato Printers |
Sato's printer monitors the take-up sensor signal. If the signal is stuck at 0 or 5 volts for 1 second, the printer detects a fault and stops the motor. The manufacturer tested this by disconnecting the sensor cable. The printer detected the fault within 1 second. |
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Chapter 20: The Sensor's Lifetime - A Wear Issue |
The sensor has a limited lifetime. The lifetime of the optical sensor is determined by the LED's lifetime. The LED's lifetime is typically 50,000 to 100,000 hours. The lifetime of the mechanical flag is determined by the micro-switch's lifetime. The micro-switch's lifetime is typically 100,000 cycles. |
Design Example: Lifetime in Brother Printers |
Brother's printer uses an optical sensor with a rated lifetime of 50,000 hours. The manufacturer tested the sensor and found that it exceeds the printer's expected lifetime. |
Chapter 21: The Sensor's Temperature Range - An Environmental Issue |
The sensor must operate over a wide temperature range. The optical sensor is typically rated for -25C to 85C. The mechanical flag is rated for -25C to 85C. The sensor must be tested at the extreme temperatures to ensure that it works reliably. |
Design Example: Temperature Range in Zebra Printers |
Zebra's printer uses an optical sensor that is rated for -25C to 85C. The manufacturer tested the sensor at -25C and 85C and found that it worked reliably. |
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Chapter 22: The Sensor's Humidity Range - A Moisture Issue |
The sensor must operate over a wide humidity range. The optical sensor is sealed to protect it from the moisture. The mechanical flag is also sealed. The sensor must be tested at the high humidity to ensure that it works reliably. |
Design Example: Humidity Range in Sato Printers |
Sato's printer uses an optical sensor that is sealed. The manufacturer tested the sensor at 95% humidity and found that it worked reliably. |
Chapter 23: The Sensor's Vibration Tolerance - A Mechanical Issue |
The sensor must tolerate the vibration. The optical sensor is a solid-state device and is tolerant to vibration. The mechanical flag can be affected by vibration. The flag is mounted on a rigid bracket to reduce the vibration. |
Design Example: Vibration in Honeywell Printers |
Honeywell's printer mounts the mechanical flag on a rigid bracket. The manufacturer tested the flag at the vibration levels and found that it worked reliably. |
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Chapter 24: The Sensor's Dust Protection - A Cleaning Issue |
The sensor can be affected by the dust. The dust can block the optical path or can get into the mechanical flag. The sensor is protected from the dust by a cover or a seal. The sensor is also cleaned regularly by the user. |
Design Example: Dust Protection in Brother Printers |
Brother's printer uses a sealed optical sensor. The manufacturer also uses a dust cover over the sensor. The manufacturer recommends cleaning the sensor every 10,000 labels. |
Chapter 25: The Sensor's Cable - A Potential Failure Point |
The sensor's cable connects the sensor to the main board. The cable can be damaged by the repeated opening and closing of the cover. The cable is a flexible cable that is designed to withstand the flexing. The cable is also routed to avoid any sharp edges. |
Design Example: Cable in Zebra Printers |
Zebra's printer uses a flexible cable that is rated for 10,000 flex cycles. The cable is routed with a large bend radius to reduce the stress. The manufacturer tested the cable and found that it exceeds the printer's expected lifetime. |
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Chapter 26: The Sensor's Connector - A Secure Connection |
The sensor's connector must be secure. The connector must not be disconnected during the operation. The connector is typically a JST or a Molex connector with a locking mechanism. The connector's pins are gold-plated to resist the corrosion. |
Design Example: Connector in Sato Printers |
Sato's printer uses a JST connector with a locking latch. The manufacturer reports that the connector is secure and reliable. |
Chapter 27: The Sensor's Replacement - A Service Issue |
The sensor can fail and must be replaced. The sensor is a modular component that can be replaced by a service technician. The replacement procedure is simple - the technician removes the cover, unplugs the sensor cable, and removes the sensor. The technician installs the new sensor and runs the calibration. |
Design Example: Replacement in Brother Printers |
Brother's printer has a modular sensor that can be replaced in the field. The technician removes the cover, unplugs the sensor cable, and removes the sensor. The technician installs the new sensor and runs the calibration procedure. |
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Chapter 28: The Sensor's Cost - A Trade-Off |
The sensor adds cost to the printer. The sensor's cost is determined by the type. The mechanical flag is the least expensive. The optical sensor is more expensive. The sensor's cost is a trade-off between the performance and the price. |
Design Example: Cost in Sato Printers |
Sato's printer uses a low-cost mechanical flag. The manufacturer chose the mechanical flag because it is sufficient for the printer's requirements and it is inexpensive. |
Chapter 29: The System Integration - Putting It All Together |
We have now covered the label take-up sensor and the jam detection system. Let us put it all together. The sensor detects the web movement. The CPU monitors the sensor and detects a jam if the web stops. The CPU stops the motors and notifies the user. The sensor is a critical part of the printer's protection system. |
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Chapter 30: The Different Jam Scenarios - A Diagnostic Aid |
There are different types of jams. The jam can be a paper jam (the label is stuck), a ribbon jam (the ribbon is tangled), or a liner jam (the liner is stuck). The printer's diagnostic can help identify the jam type. The diagnostic is based on the sensor signals and the motor currents. |
Design Example: Diagnostic in Zebra Printers |
Zebra's printer has a diagnostic that identifies the jam type. The diagnostic is based on the sensor signals and the motor currents. The manufacturer reports that the diagnostic helps the user to clear the jam quickly. |
Chapter 31: The User Interface - The LCD and the LEDs |
The user interface is used to notify the user of a jam. The LCD displays a 'Paper Jam' message. The LED flashes red. The user interface is a critical part of the jam detection system. |
Design Example: LCD in Brother Printers |
Brother's printer displays a 'Paper Jam' message on the LCD. The manufacturer chose the LCD because it provides a clear and detailed message. |
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Chapter 32: The Audible Alarm - A Beep |
The audible alarm is a beep that sounds when a jam is detected. The beep is a simple and effective way to alert the user. The beep is a piezoelectric buzzer. |
Design Example: Buzzer in Sato Printers |
Sato's printer has a buzzer that beeps when a jam is detected. The manufacturer chose the buzzer because it is a simple and effective way to alert the user. |
Chapter 33: The Remote Monitoring - An Email Alert |
The remote monitoring is an email alert that is sent when a jam is detected. The remote monitoring is used in large-scale operations where the printers are not constantly monitored. |
Design Example: Email in Zebra Printers |
Zebra's printer can send an email alert when a jam is detected. The manufacturer chose the email alert because it provides a timely notification to the operator. |
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Chapter 34: The Diagnostic - A Self-Test |
The jam detection system can be tested by the printer. The self-test is a simple test that checks the sensor. The self-test is used during the power-on and during the maintenance. |
Design Example: Self-Test in Honeywell Printers |
Honeywell's printer performs a self-test at power-on. The self-test checks the sensor's output. If the sensor is not working, the printer displays a 'Sensor Fault' error. |
Chapter 35: The Fault Detection - A Safety Feature |
The jam detection system can have a fault. The fault can be a stuck sensor or a broken wire. The fault detection is a safety feature that ensures the system is working. |
Design Example: Fault Detection in Sato Printers |
Sato's printer monitors the sensor signal. If the signal is stuck for 1 second, the printer detects a fault and stops. |
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Chapter 36: The Safety Standards - A Regulatory Requirement |
The jam detection system must comply with the safety standards. The safety standards require that the printer stops when a jam is detected. The safety standards are a regulatory requirement. |
Design Example: Compliance in Zebra Printers |
Zebra's printer complies with the IEC 60950 safety standard. The printer stops when a jam is detected. The manufacturer chose to comply with the safety standard to ensure the printer is safe. |
Chapter 37: The Future of Jam Detection - AI and Vision |
The future of jam detection lies in artificial intelligence and vision systems. A vision system uses a camera to monitor the paper path. The AI algorithm detects a jam by recognizing the pattern of a jam. The vision system is more flexible and more accurate than the current sensors. |
Design Example: Vision System in a Prototype |
A prototype printer uses a vision system for the jam detection. The vision system uses a camera and an AI processor. The AI processor detects a jam by analyzing the image. The manufacturer reports that the vision system is very accurate. |
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Chapter 38: The Future - Smarter and More Integrated |
The future of jam detection lies in smarter and more integrated solutions. The future jam detection will be integrated into the printer's control system. The future jam detection will also use AI to predict a jam before it happens. The future jam detection will be more reliable and easier to use. |
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Detailed Summary - Tying It All Together |
We have now completed our comprehensive exploration of the label take-up sensor and the paper jam detection system - the sensors and logic that protect the printer from jams and mechanical damage. We began by understanding the problem: jams are inevitable, and the printer must detect them quickly to prevent damage. We learned about the different types of sensors: the optical break-beam sensor, the reflective sensor, the mechanical flag sensor, and the encoder-based detection. Each has its advantages and trade-offs. |
We explored the signal conditioning, the debouncing, and the time-out logic. We saw how the CPU measures the sensor signal and detects a jam when the web stops moving. We examined the emergency stop circuit that cuts the power to the motors, and the coordinated stop that stops the motors and the printhead simultaneously. We looked at the user notification - the LCD message, the audible alarm, and the remote email alert. |
We discussed the practical aspects: the sensor's field of view, position, response time, noise filtering, ambient light compensation, calibration, fault detection, lifetime, temperature range, humidity range, vibration tolerance, dust protection, cable, and connector. We examined the different jam scenarios, the diagnostic, and the recovery procedure. We looked at the safety standards and the regulatory requirements. |
We considered the future of jam detection - smarter and more integrated solutions with AI and vision systems that can predict and detect jams more accurately. |
The overarching lesson is that the jam detection system is a critical safety and reliability feature. A well-designed system detects jams quickly, stops the motors safely, and notifies the user clearly. A poorly designed system can lead to motor burnout, printhead damage, and wasted labels. Understanding the jam detection system is essential for any engineer who wants to design a reliable printer, and this chapter has provided that understanding from the basic principles of the optical sensor to the advanced techniques of the AI-based vision system. |
End of Extended Section 17 |
cs@easiersoft.com