What is a Machine Vision Sensor?

Machine vision sensors are becoming more and more widely used in modern times, and in a given application, three key factors determine the choice of sensor: dynamic range, speed, and responsiveness. Dynamic range determines the quality of the image that the system is capable of capturing, also known as the ability to capture details. The speed of a sensor refers to how many images a sensor is capable of producing per second and the amount of output that the system is capable of receiving. Rescissivity refers to the efficiency with which a sensor converts photons into electrons, which determines the level of brightness at which the system needs to capture a useful image.

How machine vision sensing works

Vision originates from a way of obtaining information about the external environment in the biological world, and is the most effective means for organisms in nature to obtain information, and is one of the core components of biological intelligence. 80% of human information is obtained by vision, based on this inspiration researchers began to install "eyes" for machines to make machines and humans through "seeing" to obtain external information, thus giving birth to a new discipline - computer vision, people through the study of biological vision systems to imitate the production of machine vision systems, although very different from human visual systems, but this is a breakthrough in sensor technology. The essence of vision sensor technology is image processing technology, which intercepts the signal from the surface of the object and draws it into an image to present it in front of the researcher.

Vision sensors have thousands of pixels that capture light from an entire image. The sharpness and detail of an image is usually measured in terms of resolution, expressed in the number of pixels. After capturing the image, the vision sensor compares it to a benchmark image stored in memory for analysis. For example, if a vision sensor is set to identify a machine part with eight bolts inserted correctly, the sensor knows that it should reject parts with only seven bolts, or parts with misaligned bolts. In addition, the ability of vision sensors to make judgments regardless of where the machine component is located in the field of view, whether or not the part is rotating within a 360-degree range, has been welcomed by the industrial manufacturing community because the advent of vision sensing technology has solved the problem that other sensors cannot operate due to the size of the site or the large size of the inspection equipment.

Visual sensing technology includes 3D visual sensing technology, 3D visual sensors have a wide range of uses, such as multimedia mobile phones, network cameras, digital cameras, robot visual navigation, automotive safety systems, biomedical pixel analysis, human-machine interface, virtual reality, surveillance, industrial detection, wireless long-distance sensing, microscopy technology, astronomical observation, marine autonomous navigation, scientific instruments and so on. These different applications are based on 3D vision image sensor technology. In particular, 3D imaging technology has an urgent application in industrial control and automotive autonomous navigation.

Intelligent visual sensing technology is also a kind of visual sensing technology, and the intelligent visual sensor under intelligent visual sensing technology, also known as smart camera, is a new technology that has developed rapidly in the field of machine vision in recent years. The smart camera is a small machine vision system with the functions of image acquisition, image processing and information transmission, and is an embedded computer vision system. It integrates image sensors, digital processors, communication modules, and other peripherals into a single camera, reducing system complexity and increasing reliability thanks to this all-in-one design. At the same time, the size of the system is greatly reduced, which broadens the application field of vision technology.

The advantages of smart vision sensors are easy to learn, easy to use, easy to maintain, easy to install, and can build a reliable and effective visual inspection system in a short period of time, which makes this technology develop rapidly. The image acquisition unit of the vision sensor is mainly composed of a CCD/CMOS camera, an optical system, an illumination system and an image acquisition card, which converts the optical image into a digital image and transmits it to the image processing unit.