This post was written by Tracie Cooper and originally appeared on Aven.com. We picked it out because it does a great job describing how you can select the different components that make up your video inspection system.
HOW TO CREATE YOUR VIDEO INSPECTION SYSTEM
Posted by Tracie Cooper
There are a lot of options available when it comes to imaging systems. This is a good thing, as there is almost certainly an imaging system that will suit your individual needs. Here are some tips for finding the best system for your applications.
SELECT YOUR LENS
First, consider these four key elements:
- Field of View
- Depth of Field
- Working Distance
These will determine what sort of lens is required for your ideal imaging system. A field of view is the area that the lens can see, and depth of field is the area in focus at one time under magnification.Very small objects will require a micro lens with a higher level of magnification and lower depth of field. Larger objects will require a macro lens, which will offer a lower level of magnification and higher depth of field. Additionally, higher magnification reduces working distance while lower magnification increases working distance.
Once you’ve determined your field of view and chosen a lens, think about your overall goals. What are you viewing, and what do you want to do with it? Whatever the objective, you want the highest possible level of image resolution. At this point, it’s time to think about cameras.
SELECT YOUR IMAGING CAMERA
Two of the most common imaging sensors found in digital cameras are CCD and CMOS. CCD stands for “charge-coupled device” and are designed to help remedy challenging lighting and color conditions. Despite low light applications or very small objects of study, the CCD sensor provides extremely precise color reproduction and highly detailed images, capturing a precise, high resolution images of moving objects. CCD cameras are ideal for examining things like cell structures, and are a popular choice among medical researchers.
CMOS stands for “complimentary metal oxide semiconductor” and is a great choice for parts inspection, clinical and industrial research, and any imaging application wherein it is critical to reduce lag time from one image to the next. Images from a CMOS camera are known for exceptional clarity, which greatly enhances the operator’s experience making measurements and annotations.
Inspection cameras come with several output options including USB and HDMI. Your choice will determine speed of frame rate and how images are viewed. Cameras with a USB 2.0 or 3.0 output both connect directly to your computer (as a result, a PC is required to view these images). Though both USB outputs function in the same manner, USB 3.0 is faster and helps to reduce lag timebetween images. USB cameras generally come feature rich software for image capture, annotations and measurements.
Cameras with an HDMI output connect directly to an HD monitor, eliminating the need for a computer. This saves bench top space and removes the image lag time that occurs with USB image processing. HDMI cameras generally come with an SD or USB flash drive for saving images. More advanced models come with imaging and measurement software.
SELECT YOUR ILLUMINATION
Next, think about illumination. LED ringlights are ideal for macro lenses and lower range magnifications, while Fiberoptic Illuminators (FOI) provide intensity and focus of light, and work well with micro lenses and high-range magnifications. They also save a significant amount of energy, making them better for both the environment and your budget. Backlights are generally placed underneath the object to be viewed and connected to the fiberoptic illuminator for further enhancement. A polarizer is essential for viewing shiny parts, as it helps to eliminate glare and bring out surface details.
If you are looking at highly specular or shiny surfaces and need hot spots and glare to be completely eliminated, we recommend our Diffuse Axial LED Illuminator. This, when attached to our stereo microscopes, will provide a very high level of clarity.
Lastly, choose a stand appropriate to the size and weight of your inspection system. High quality stands are made of durable material that is resistant to shaking and vibrations. Some models will have built-in mounts for attachments. Once this simple and final step is completed, you’ll have created a video inspection system tailored to your application, ready to work for you.