How have industrial cameras changed in the past ten years?

Looking back on the development history of industrial cameras over the past 50 years, it is not difficult to see that CCD cameras and CMOS cameras have long coexisted and occupied the entire industrial camera market; looking to the future, digital cameras will replace analog cameras and become the key to the development of machine vision technology. Faced with market demand, why can CCD cameras and CMOS cameras coexist for a long time? What advantages do digital industrial cameras have that can lead them to the top? .

Dior Company elaborated on the development trend of industrial camera standards from three aspects: industrial camera classification, differences between CCD cameras and CMOS cameras, and advantages of digital cameras, and made development forecasts for corresponding market demands. The following are the specific contents:

The selection of industrial cameras is generally determined based on needs, and it is particularly important to be familiar with the classification of industrial cameras.

• According to the chip type, it can be divided into CCD cameras and CMOS cameras;
• According to the sensor structural characteristics, it can be divided into line scan cameras and area scan cameras;
• According to the scanning method, it can be divided into interlaced scan cameras and progressive scan cameras;
• According to the resolution, it can be divided into ordinary resolution cameras and high resolution cameras;
• According to the output signal mode, it can be divided into analog cameras and digital cameras;
• According to the output color, it can be divided into monochrome (black and white) cameras and color cameras;
• According to the output signal speed, it can be divided into ordinary speed cameras and high-speed cameras;
• According to the response frequency range, it can be divided into visible light (ordinary) cameras, infrared cameras, ultraviolet cameras, etc.

The principles of CCD cameras and CMOS cameras are basically the same. The differences exist in their performance, including:

• Noise difference. Since each photosensitive diode of CMOS needs to be matched with an amplifier, while CCD only needs one amplifier placed on the edge of the chip, compared with CMOS, CCD has relatively less noise, and the image quality will be correspondingly higher;
• Difference in power consumption. CMOS uses an active image acquisition method, while CCD uses a passive acquisition method, so the CCD consumes more power than CMOS;
• Resolution difference. Since each pixel of CMOS is more complex than CCD, but the pixel size does not reach the level of CCD, Therefore, when CCD and CMOS are of the same size, the resolution of CCD is usually slightly higher;
• Difference in sensitivity. Because CMOS reads signals directly from dots, while CCD reads signals indirectly from rows, the sensitivity of CCD is higher than that of CMOS;
• Cost difference. Since controlling the yield of CCD is more troublesome than that of CMOS, the manufacturing cost of CCD is relatively higher than that of CMOS. In other words, what standard industrial camera is the development trend is completely determined by customer needs and market demand. For example, if the market needs something cheap and low in power consumption, then CMOS cameras will be the development trend; if the market needs high resolution and good photosensitivity, then CCD cameras will be the development trend.

Let’s take a look at the differences between digital cameras and analog cameras. In fact, most market participants believe that digitization will be the development trend in the field of machine vision and is the standard type of industrial cameras. They are very optimistic about the prospect of digital cameras replacing analog cameras. Then, let’s focus on digital cameras. Digital industrial cameras are divided into four categories according to different interface standards:

• USB has the advantages of low cost, fast transmission speed, easy use, flexible connection, and independent power supply.
• 1394 has a relatively high cost, but the transmission speed is faster.
• CameraLink can solve the problem of large data transmission.
• Gige can solve the problem of long-distance transmission.

From this point of view, the choice of standards is still determined based on market demand.