Whether used to identify dangerous situations or to assist in locating suspects, Fixed Mount Cameras provide a cost-effective option for a wide variety of applications. To choose the best model for your application, you must consider a number of different factors.
For example, there is the matter of sensitivity, image quality and field of view. Other specifications include mounting direction, lens mount size and flange distance. Keep reading the article below to learn more about Vision Detection Systems.
A thermal camera’s sensitivity is a key metric to understand and consider when selecting a model for your application. Sensitivity refers to how easily the core detects temperature differences and is measured in milliKelvins (mK). The lower the number, the more sensitive the device is.
A common misconception is that a lower sensitivity means less accurate readings, but this is not necessarily the case. The sensitivity of the camera is affected by a number of factors, including the size and type of lens, the image sensor, the camera’s temperature calibration and more.
The sensitivity of a thermal imaging camera is determined by the amount of light it can collect and convert to a digital signal that can be interpreted by the core. The number of photons collected is dependent on the exposure time and light intensity, which is why it’s important to understand the physics of a thermal imaging camera.
In a thermal imaging camera, the exposure time is determined by the integration period of the image sensor. As the integration period increases, the effective sensitivity decreases. A longer integration period requires more light to capture a sufficient signal for processing, which results in poorer performance.
Another factor affecting the effectiveness of a thermal imaging camera is the pixel size and type. The larger the pixel size and type, the more light it can collect for processing. However, a large pixel size and type can result in false pixels, which can cause the image to appear distorted or blurry.
A common method to mitigate this effect is the use of a gamma curve in the camera’s signal processing pipeline. Gamma correction compensates for the nonlinear response of CRT displays and the logarithmic response of the human eye, making noise more evenly distributed across all brightness levels.
FLIR Axxx-Series fixed mount cameras offer a variety of field-of-view choices and radiometric streaming capabilities, enabling you to monitor your industrial processes with the specific functionality you require. The combination of these features ensures your remote monitoring solution can tackle all of your quality, maintenance, production and safety needs.
Image Quality
A good quality camera can make a difference when you’re trying to identify problems during an inspection. A high refresh rate can help ensure that you have a clear image and are able to detect any changes in temperature quickly. However, a higher refresh rate can also increase power consumption, so it’s important to balance the need for a high refresh rate with other factors like cost and battery life.
Depending on your application, you may want to choose a fixed mount thermal imaging camera that supports one or more industry standards. For example, many manufacturers offer cameras that are compatible with Gigabit Ethernet (GigE Vision), which allows for fast transfer of images over long distances. This makes it easy to connect the camera to your network and use third-party software.
Another option is to choose a camera that uses the GenICam standard. This is a standard that defines an Application Programming Interface (API) for cameras. This allows you to develop software that can control multiple different camera models, regardless of the type of interface they use. This can save time and money because you don’t have to spend time integrating the camera with each type of software.
You should also consider the resolution of your camera. The higher the resolution, the better the image quality will be. A higher resolution camera will be more expensive, but it can provide you with a more detailed image. Choosing a higher resolution camera can also help you to detect small defects or errors in your process.
The image quality of a fixed mount thermal imaging camera is also determined by the color palette that is used. Most cameras will default to a white and black color palette, but some will allow you to select your own color palette. The image quality can also be affected by the value of gamma used. The gamma value is the ratio of the image’s brightness to its contrast. Typically, a gamma of 2.8 or 2.2 is used to produce a more visually pleasing image.
A fixed mount thermal imaging camera can be a great tool for your inspections. With the right settings, you can easily find and fix any issues that might be present in your process. This will help to improve your productivity and reduce downtime.
Field of View
A camera’s field of view determines what it can see and how much detail is captured. This is particularly important for vision systems used in industrial automation. In this blog post, we’ll take a closer look at how FOV impacts machine vision applications and offer some insights for selecting the right lens for your application using Cognex’s Lens Advisor tool.
FOV is the open, observable area a camera can see at one moment through its lens or viewfinder. It can be described in terms of a horizontal or vertical field of view, an angular field of view, or both. A wider field of view covers more space but sacrifices some detail, while a narrower one captures more detail but may not cover as much area.
The size of the object in front of the camera also influences its FOV. Generally, larger objects require a higher magnification to be clearly imaged, so they will have a smaller FOV than smaller objects.
Moreover, the angle at which the lens is directed to the object also affects its FOV. A straight-on angle will deliver a narrower FOV than an oblique angle, as the lens must bend the light in order to capture all of the object’s features.
Another factor that influences FOV is the desired resolution for an image. A high-resolution camera requires a narrower FOV to maintain clarity and avoid pixelation, while a lower resolution camera can use a wider FOV.
Lastly, the FOV of a camera can be affected by its aperture and focal length. A wide aperture, or f-stop, allows more light to pass through the lens and increase its FOV, while a narrow aperture limits the amount of light that can reach the sensor and decreases its FOV.
Video Output
Modern CCD digital video cameras, as shown in Fig 4.3, can achieve high resolutions and image quality suitable for photogrammetric applications. The camera’s output images are passed directly to a personal computer (PC) for storage and processing. To ensure proper interaction between the camera and the host PC, a frame grabber is typically used. The frame grabber under software control continuously reads the camera’s video output, adjusts the camera’s settings as necessary, and carries out real time image analysis tasks. It also provides process synchronization, a key requirement in applications where multiple cameras are involved.
A PC based system with a powerful graphics card provides virtual graphics that can be overlayed on the camera’s live video image. In order to make the virtual image synchronized with the camera position and field of view, the graphics card must be capable of producing a scan converter that matches the camera’s video signal frame rate, referred to as “genlock”. This is required to avoid visible drift between the real and virtual graphics.
The TV camera is equipped with a lens sensor that measures the camera’s zoom and focus settings, along with a tracking system to measure the camera position and orientation. This information is sent at a video rate (50 or 60 Hz) to a graphics rendering system, which generally consists of a high-end PC with a powerful graphics card. The graphics card then renders the virtual elements in the scene, with the camera position, orientation, and field of view matching those measured by the tracking system.
In some application environments, a single fixed camera is appropriate for a pick and place cycle. This configuration can reduce application cycles by reducing the amount of image capture and processing performed by the robot in parallel with object detection. However, the use of a single camera requires that it be adequately protected and isolated from vibration sources and routed out of the space occupied by the robot motions. Additionally, the hardware setup can be a significant expense, especially for large systems.