Labels are usually attached to products to identify and transmit information. Label sensor is a device that can monitor and remind you whether the product label is correct.
In the automatic labeling, packaging and testing equipment update iteration speed soaring, the label sensor should be suitable for accurate identification of different types of label materials, to ensure that the labeling process is stable and efficient.
The variety of labels and the great difference in optical properties of different materials highlight the importance of selecting the right sensor.
With a series of innovative sensors from Gtric, including diffuse reflection photoelectric Sensors, non-transparent label sensor, BGS photoelectric sensors, and digital color-labeled photoelectric sensors. Based on four typical detection scenarios, we will explain and recommend the actual scenarios that you may have, to help you make the best choice in a complex labeling environment.
1. Detect Transparent Objects
Requirements: Transparent labels are widely used in beverage bottles, pharmaceutical bottles, cosmetics packaging and other industries.
The transparency of transparent materials is extremely high, and there is almost no reflection difference between the label and the base paper. To achieve accurate labeling, the object must be detected as high as possible in order to start the labeling operation.
To this end, sensors need to stably identify objects of various types and shapes, including transparent objects. Meanwhile, the replacement of products should not affect the labeling process.
Solution: E3JK series reflective photoelectric sensors achieve stable recognition of light through polarization filters and mirrors. When the transparent or semi-transparent label passes through the detection area, the intensity of the reflected light will change slightly, and the sensor can capture and output the signal instantaneously.
It has strong anti-external light interference performance, convenient adjustment sensitivity, and can also adapt to labels of different materials.
2. Detect Non-transparent Labels
Requirements: Paper or PVC non-transparent labels should be attached to the product packaging.
Due to the obvious difference in reflection, the detection method is relatively simple. But attention should be paid to the gap between labels.
The label sensor should also be able to reliably detect tags with complex shapes to avoid inaccurate labeling or machine downtime.
Solution: 40mm-60mm non-transparent label detection sensor, which adopts the principle of transmission detection––the transmitting end emits a beam and the receiving end receives it.
When the label passes through, the light beam is blocked or absorbed, and the system instantly recognizes the label position.
3. Monitoring of label tape
Requirements: For the label machine with a long tape route, label detection is not only to identify a single label. It also includes monitoring the running state of the whole label belt to prevent belt breakage, deviation or abnormal feeding.
Solution: BGS photoelectric sensor realizes distance-based detection through background suppression technology.
It does not depend on the color or reflectivity of the label, but determines the distance difference between the object and the background, which can effectively avoid the detection error caused by material changes.
When using the BGS sensor, it should be ensured that the sensor and the label band maintain a fixed distance to obtain the most stable detection effect.
4. Detection of Color label
Requirements: For printing packaging, color labeling and other scenes, the sensor needs to identify color or printing mark differences.
This kind of detection requires higher accuracy, because small color differences may affect the detection results.
Solution: The color mark photoelectric sensor adopts RGB three colors light source detection technology. By measuring the reflected light intensity of different colors, it can accurately identify the label color mark, printing mark or pattern. It can store multiple color settings and switch quickly. At the same time, it also supports the automatic learning function and one-click calibration.
| Application Scene | Recommended Sensor Type | Typical Characteristics and Advantages |
| Transparent label detection | Reflective photoelectric sensor – E3JK series ) | Stable identification of transparent / translucent objects, strong anti-interference |
| Non-transparent label detection | Transparent photoelectric sensor –40mm-60mm series | Fast and accurate detection, suitable for high-speed labeling line |
| Tag tape monitoring | Background Suppression Photoelectric Sensor – BGS Series ) | Not affected by color, suitable for broken belt detection |
| Color label detection | Color mark photoelectric sensor | Identify the printing color mark, suitable for color packaging |
The key to selecting a label sensor is to understand the optical properties of the label and the working conditions of the device.
Appropriate sensors can not only improve the detection accuracy, but also reduce accidental shutdown and manual calibration, thereby improving the overall production efficiency.
Contact Gtric to help you achieve a more efficient and stable automatic labeling process by reasonably selecting the sensor.