If you are looking for the right type of camera to use for your machine vision system for industrial inspection and to better control, troubleshoot, tweak and improve your production processes and product quality, you need to understand the difference between the two type of sensors, CCD and CMOS as well as their benefits and weaknesses for this particular purpose.
Also, of course, you have to keep in mind the expenses included in the purchase and the use of the two types of sensors, which is also essential for determining the most appropriate cameras to use for your business needs.
Differences between CMOS and CCD camera sensors
CMOS sensors are relatively new as compared to CCD sensors. The CMOS (complementary metal oxide semiconductor) sensors are produced in a similar fashion as any other integrated chip technologies, microprocessors or microcontrollers. This is a much faster, automated and less complicated production process than that involved in producing CCD (charged-coupled devices).
CMOS sensors integrate all components needed to capture an image, convert it to digital and process it on one chip, while CCD sensors include a number of different components in their system for producing images. This makes the process much slower and power consuming, but the end result is usually better quality and uniform images with no noise or distortion.
Due to the much faster and simpler production process of CMOS sensors, they are significantly less expensive than CCD sensors. This, of course, is a vital factor when planning on investing on the best camera for your business needs.
But for the best results, you need to consider the differences in the performance, power usage, speed and ease of use of the CMOS and CCD cameras as well.
CCD sensors are more complicated to make and use, but they provide images with little or no distortion or noise and of higher quality than CMOS sensors do.
At the same time, the image capture and processing by CCD cameras are much slower, uses about 100 times more power and is much more complicated than that provided by CMOS cameras.
CCD sensors allow for better customizing and optimization and work better in cases of insufficient lighting, but CMOS sensors are constantly improving with the advancement of technology so they can be a superb choice if you want a high speed, high quality, power saving and less expensive camera for your business needs.
Some of the pros and cons of CCD and CMOS cameras
Depending on your preferences and needs as well as the results expected you can choose between the two types of cameras based on these main pros and cons of both types of sensors:
The pros of these types of sensors include: excellent reproducibility and output uniformity, top quality conversion from analog to digital imaging, low noise or distortion of the images, better light sensitivity. Their cons are that they are more expensive than CMOS cameras, they use a lot more power and are much slower than the other type of sensors.
The pros of the CMOS sensors are that they have a much higher readout speed than CCD, they are less expensive, they use less power, they are smaller so they can fit in tighter spaces and they are easier to use. The cons of CMS cameras include their lower uniformity in the output, the varying sensitivity, and linearity between pixels, the images produced can be distorted or feature noise.
How CMOS cameras for business are improving
In the latest years, the quality and performance of CMOS cameras for industrial use has been continuously improving. Now they are getting even faster and provide higher light sensitivity and resolution. These sensors are being vigorously developed and improved mainly due to the increase of the popularity of smartphones and the increasing demand for the quality of their on board cameras by the growing number of smartphone users around the world. This has led to a vast improvement in the quality and sensitivity of these types of sensors in the last few years.
Since industrial inspection machine vision systems aim at increasing the production efficiency which is measured through the total output, yield, product return, downtime for troubleshooting and repairs and other factors, there is a continuous demand for overall improvement of the speed, power consumption, resolution and the cost of such systems.
CMOS sensors work at a much greater speed which is essential for inspection and control of continuous fast-moving production processes and conveyor lines. The improved resolution of the CMOS cameras in the latest years helps capture images with much more detail, and their improved light sensitivities allow for their implementation in the machine vision systems without having to invest too much in supplemental lighting.
This is why more industries are choosing to invest in CMOS sensors for their inspection and quality control needs both for line scan cameras and for area scan cameras for the machine vision systems.
On the other hand, CCD sensors still remain the leading choice when the goal of an industry is to achieve maximum uniformity and dynamic range, but their use is expected to become even more niche and specialized.
When choosing which type of cameras to purchase for your business needs, always keep in mind what your expectations for the results are, what the lighting conditions and space availability are, what budget you have planned for your machine vision system for inspection or control, as well as the other components and software you are planning to use with your camera.
The proper set up and synchronization of all the components of the entire machine vision system is essential if you want to get the results you are expecting and improve your production quality and better production process control.
It is a good idea to ask an expert or consultant to help you with your decision making. After all, you want to be sure that you are making the best investment and that the system for automatic inspection and control will yield the results you expect and improve your overall production.