Top 3, What Hardware is Needed for a Computer Vision Camera Application?
Computer vision, also known as machine vision or image processing, is the ability of a computer to see, analyze the image and then make a decision. Computer vision is applied in for example industrial or practical applications. For a computer to be able to see (image processing) the following hardware components are required as a minimum:
Camera, preferably a computer vision camera
Lens, this determines the field of view
Cable, this connects the computer vision camera with the computer
In addition, the following hardware components are also often used in image processing:
Lighting, for properly illuminating what the computer must see
Lens filters, for removing ambient light and specific colors
With the above hardware you can realize the perfect computer vision camera application.
5 Steps for Selecting Computer Vision Products
To select the right hardware products for computer vision you must go through the following steps:
Step 1, how detailed should the computer vision camera look?
The first choice to be made with a computer vision camera application is how much detail the computer must see. This is determined by the field of view and the smallest detail that must be visible. Suppose you have a computer vision application where you want to count marbles. Each marble has a diameter of 10mm. In total the field of view must be 2x2 meters, or 2000x2000mm. To stably detect the marble through computer vision, each marble must have a size of at least 2x2 pixels. That means that a marble of 10x10mm corresponds to 2x2 pixels and 1 pixel = 5mm. If the field of view of the computer vision camera is 2x2 meters, then the minimum resolution for the eyes of the computer is (2000/5) x (2000/5) = 400x400 pixels. The resolution of the computer vision camera must then be at least 400x400 = 0.16MP. For further support in selecting the right computer vision camera, we recommend that you read this page carefully.
Step 2, how large is the field of view / field of view of the computer vision camera?
The field of view of the computer vision camera is determined by the sensor size and the focal length of the lens. These together determine the opening angle of the lens. For the sensor, the larger the sensor, the larger the field of view. The field of view of a 2/3 "sensor is twice as large as the field of view of a 1/3" image-sensor. For the lens, the lower the focal length, the larger the field of view. A lens with a focal length of 4mm gives a field that is twice as large as a lens with a focal length of 8mm. For further support in choosing the right lens for a computer vision camera, we recommend that you read this page carefully and make use of our lens calculator.
Step 3, how do I connect the image computer vision camera to the computer?
Use a cable to connect the computer vision camera to the computer. Which cable you need depends on the camera interface. If you use a USB2 or USB3 computer vision camera, we always recommend using the USB2 and USB3 cables that we offer. A high quality cable is required for a stable image transfer. With a GigE computer vision camera you can in principle use any standard Cat5e cable. The cables that we offer have the advantage that they are attached to the computer vision camera housing by means of two screws. This creates a more stable connection in computer vision applications where the computer vision camera, for example, moves. There are also special high-flex cables that are suitable for computer vision applications where the cable bends regularly, as is the case with a robot.
Step 4, which lighting do I need to make a robust computer vision application?
For a computer vision application it is important that what one wants to see is well illuminated. In some cases the ambient light is sufficient. However, in many computer vision applications the lighting is used to accentuate the object to be detected. If you need advice on which lighting is suitable for your computer vision application, please contact us. We have a lot of experience in the field of lighting for computer vision applications.
Step 5, do I need a lens filter for my computer vision camera?
In computer vision, lens filters are used to add more contrast to the image. This extra contrast is achieved because the lens filter only transmits specific light wavelengths (colors). Ambient light or specific wavelengths will be blocked and additional contrast is created. Typical examples in computer vision are blue lighting with a blue lens filter and a red light with a red filter or an infrared light with an infrared filter. An overview of our lensfilters for computer vision cameras can be found on this page.