Industrial camera composition Industrial camera selection

Industrial camera components

Industrial cameras are a key component in machine vision systems. Their most essential function is to convert optical signals into orderly electrical signals. Selecting a suitable camera is also an important part of machine vision system design. The choice of camera not only directly determines the resolution and quality of the collected images, but is also directly related to the operating mode of the entire system.

Industrial cameras are mainly composed of the following parts:

1. Image sensor: It is the core component of industrial cameras and usually uses CMOS or CCD sensors.

2. Camera circuit board: including image sensor control chip, A/D conversion, USB or GigE interface, etc.

3. Lens: responsible for focusing the light reflected from the object onto the sensor.

4. Filter: used to filter out unnecessary light.

5. Light source: Provide appropriate lighting conditions to ensure high-quality images are captured.

6. Casing: Usually made of metal to protect internal electronic components from damage.

7. Other auxiliary components: such as fans, radiators, power supplies, etc., to ensure the normal operation of industrial cameras.

Industrial Camera Selection

The selection and model selection of suitable industrial cameras are very important in machine vision systems. The suitability of industrial cameras directly determines the operating results of the entire machine vision system. Since the selection and model selection of industrial cameras are so important, how do you choose a suitable industrial camera? In order to help those who need industrial cameras, Dushen Technology will talk about the selection method of industrial cameras and the dimensions from which to start so that those who need them can choose the industrial camera that suits them.

1. Application scenarios

There are many industrial application scenarios, such as surface defect detection, object positioning detection, rapid scanning detection, etc. These different application scenarios have different requirements for industrial camera parameters such as pixels, frame rate, spacing, and light.

For example, surface defect detection has high requirements on light, pixels and clarity, while object positioning detection requires accurate recognition and algorithms. In addition to ensuring clarity, fast scanning detection also requires high frame rate and fast speed. Even for the same object surface defect detection, metal surface detection and cloth and paper surface detection have completely different requirements for industrial cameras.

Metal surfaces reflect light, so metal surface inspection requires a relatively high light source, and the industrial camera must be able to identify the bright and dark sides. Cloth and paper surface inspection requires higher requirements in terms of color, material, and clarity. Therefore, the application scenario determines what kind of industrial camera should be used.

2. Resolution selection

Resolution usually refers to the number of pixels contained in the image sensor, expressed as length * width. The 1 million pixels, 5 million pixels, 10 million pixels, and even over 100 million pixels that we all know are calculated from the resolution.

There are two things to consider when choosing a resolution:

Determine the accuracy of the target. If the target accuracy cannot be determined, the choice of resolution is meaningless. Industrial camera pixel accuracy = single-direction field of view size / camera single-direction resolution. In addition, the pixel accuracy of industrial cameras must be higher than the accuracy required by the target, so that it has actual measurement meaning.

The output of industrial cameras. VGA or USB output has high requirements for the resolution of the display. If the resolution of the industrial camera is higher than the resolution of the display, the high-resolution advantage of the industrial camera cannot be demonstrated. For integrated observation machines (including software analysis and recognition), there is no worry in this regard, so the higher the resolution, the better.

3. Frame rate selection

Frame rate, the full name is frame rate, refers to the number of frames of the image collected per second, in layman's terms, it is how many photos the camera can take per second. The choice of frame rate depends on the speed of the object being measured. If the speed is fast, choose an industrial camera with a high frame rate. Otherwise, choose a low frame rate.

If the actual application scenario requires both high resolution and high frame rate, it is necessary to find a bus with a larger bandwidth, which is the output interface of the industrial camera.

4. Chip selection

Industrial cameras are classified into two types based on the chip: CCD and CMOS. CMOS chips have replaced CCD chips in the market due to lower cost and lower power consumption under the same imaging quality. Only in some application scenarios with higher collection speed, higher quality images and resolution, it is better to use CCD.

5. Shutter and exposure selection

The shutter in a camera is a device used to control the exposure time of light to the photosensitive element, protecting the chip inside the camera from the impact of incident light. It will only open when it is exposed. The shutter is used to control exposure, and the global shutter and rolling shutter are the two most common shutter methods in industrial cameras. If it is used for dynamic shooting (flying shooting), the global shutter is required; static shooting is only suitable for rolling shutter.

6. Transmission interface selection

The transmission interface refers to the transmission protocol used to transfer the captured images from the industrial camera to the computer. Different interfaces have different acquisition and transmission speeds. Common ones include GigE (commonly known as Gigabit Ethernet camera), USB3.0 (commonly known as USB3.0 camera), CameraLink, etc.

7. Color selection

Industrial cameras are divided into color and black and white. Generally speaking, it is better to choose black and white industrial cameras, which can meet the needs of most application scenarios. Industrial cameras are selected in color only when there is a need to identify colors. In addition, choosing a black and white industrial camera avoids the step of converting color to black and white images and then calculating them, which simplifies the process and can improve image quality to a certain extent.

8. Brand selection

A good brand represents excellent product quality, excellent after-sales service, and complete technical support, which is no exception in the industrial camera industry. Although the most important thing about industrial cameras is the effect of the collected images, a good brand can save companies and factories time and effort and reduce unnecessary troubles during use.

The above eight dimensions are used to analyze the selection method of industrial cameras. Starting from your own application scenario, combine external factors and internal conditions to select the most economical, worry-free, labor-saving and effective industrial camera for yourself.