The line scan camera is a camera that uses a linear array image sensor. In the past, most of the chip of the line camera was CCD, but now more of the mainstream products adopt CMOS.
The line scan camera is typically applied to continuously inspect products, such as textiles, roller products, and in the process of coating and die-cutting of the front end of new energy lithium batteries.
(1) When calculating the accuracy of the line scan, the length of the product is not considered, only the width, that is, the width of the product, is considered. The length of the product is scanned by the movement of the line scan camera or the movement of the product. So we only pay attention to the accuracy of the width. Therefore, this calculation of the line scan camera is the same as that of the surface camera. Take an example: for 200MM width, resolution accuracy needs to be 0.05MM, and required pixels=200/0.05=4000. The popular term of line scan is generally 1K, 2K, 4K, 6K, 8K, 12K, 16K. 1K here can be understood as: 1024 pixels, 4K=4X1024=4096 pixels. This also has a certain relationship with the chip manufacturer, so 1024 is just a general value. It can be seen from the above that with this accuracy, the resolution of the line scan camera should be at least 4K or higher.
(2) Calculation of scanning speed. At present, the transmission of line scan camera can be divided into methods of network port and came link. The choice is mainly based on the speed requirements we have in the application. The two methods are mainly different in the transmission speed. This speed actually determines the line frequency of the line scan camera itself. So how to choose the line frequency? First, we must first understand how many millimeters(MM) our line scan camera needs to move in one second, or how many MM the product needs to move in one second. For example, in terms of 200MM width and 0.05MM accuracy, we need to move 100MM in one second, then the line frequency is calculated as follows: Line frequency=100/0.05=2000 (2KHz). Then the line scan camera I choose should boast 4K Resolution and a scanning line frequency of above 2KHz to meet the demand.
The above explains the working principle of the line scan camera and its preliminary selection process. It should be noted that there are many types of interface for line scan cameras, and the commonly used ones are F port, M port, and V port.
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