Talking about the common questions about optical lenses

1. What is the cause of the frame loss of the optical lens? There are often some machine vision engineers who believe that the optical lens of the USB interface can cause frame dropping. In general, the high precision ZnS optics drop frame has nothing to do with the transmission interface used by the camera, whether it is USB, 1394, GigE, or CameraLink. A poorly designed driver or camera hardware is the real cause of frame loss: the reason why a poorly designed camera loses frame is that the data channel is blocked and cannot be processed in time, so when a new image comes in, the previous one Zhang may be forced to discard, or new images are forced to be discarded. To solve this problem, the designer needs to precisely design each part of the driver and optical lens hardware data transmission. 2: What are the optical lens input and output interfaces? In the machine vision detection technology, the camera's input and output interfaces are Camera Link, IEEE 1394, USB2.0, Ethernet, and USB3.0. 3. Know the length, width, height and required measurement accuracy of the measured object. How to choose CCD camera and optical lens, what should you pay attention to when selecting the above device? First choose the right optical lens. The following principles should be followed when choosing a lens: 1). What is the size of the chip of the wholesale large size optical grade sapphire optics that matches it; 2). What type of interface is the camera, C interface, CS interface or other interface; 3). Working distance of the lens; 4). Lens field of view; 5). Spectral characteristics of the lens; 6). lens distortion rate; 7). The mechanical size of the lens; When choosing a CCD camera, you should consider the following aspects: 1). Photosensitive chip type; CCD or CMOS 2). Video features; including point frequency, line frequency. 3). Signal output interface; 4). Camera working mode: continuous, trigger, control, asynchronous reset, long time integration. 5). Video parameter adjustment and control methods: Manual, RS232. At the same time, when choosing a CCD camera, you should pay attention to l inch = 16mm instead of 25.4mm. 4. How is the resolution of the optical lens defined? The resolution is the basic parameter of the optical lens, which is determined by the resolution of the chip used by the camera, and is the number of pixels arranged on the target surface of the chip. Usually the resolution of an area array camera is represented by two numbers, horizontal and vertical resolution, such as: 1920 (H) x 1080 (V), the front number represents the number of cells per line, that is, a total of 1920 pixels, the following numbers Represents the number of rows of cells, that is, 1080 lines. The resolution of custom LiF optics now usually indicates how many K, such as 1K (1024), 2K (2048), 3K (4096), and so on. The resolution of the camera has a large impact on image quality when capturing images. When imaging the same large field of view (the range of scenes), the higher the resolution, the more obvious the detail is displayed. 5. What is the meaning of the frame rate and line frequency of the optical lens? The frame rate/line frequency of the camera indicates the frequency of the image captured by the camera. Usually, the area camera uses frame rate. The unit fps (Frame Per second), such as 30fps, means that the camera can capture 30 frames in 1 second. Line camera Usually the line frequency is in units of KHz. For example, 12KHz means that the camera can acquire 12000 lines of image data in one second. Speed ​​is an important parameter of the camera. In practical applications, it is often necessary to image moving objects. The speed of the camera needs to meet certain requirements in order to accurately and accurately image the object. The frame rate and line frequency of the camera are first affected by the frame rate and line frequency of the chip. The high design speed of the chip is mainly determined by the high clock that the chip can withstand.