This edition of our newsletter is a web page focused on providing imaging hardware configurations designed for high magnification, including cameras, optics, and lighting components. Whether imaging semiconductor wafers, solar cells, electronics, lab-on-a-chip, slides, or biological samples, the goal is to provide similar optical quality and magnification found on large and expensive microscope-based systems, but in a purpose-built and much more compact industrial imaging solution. The high-magnification imaging configurations detailed address a range of application models. The final Bill of Materials is going to depend on many usage factors, but the configurations described provide a good basis on which to begin selecting imaging system components for the application at hand.
Each configuration includes a camera, a high-magnification lens system, and an example of one type of lighting. Our focus is on effectively enabling high-magnification imaging in a compact and relatively inexpensive industrial solution that can be integrated into an OEM machine, on a manufacturing process line, or into an R&D environment.
The Pixelink PL-X9512 10GigE Camera is from the high-performing PL-X machine vision camera series. The 10GigE interface is similar in speed to CoaXPress and is capable of cable lengths up to 100m on CAT6A cable. This camera model features a 12MP Global Shutter 1.1” format sensor, with 4096 X 3000 pixels. These cameras are available as an enclosed or board-level product and come in 7MP, 12MP, 20MP, and 24MP versions.
Navitar’s Resolv4K Fixed lens system provides high optical performance at a fixed magnification factor, with flexible field-of-view and working distance options and sufficient resolving power to support the large format high resolution PL-X camera series.
Many high-magnification imaging systems rely on the use of coaxial through-the-lens lighting to provide lighting similar to a microscope’s. The Navitar Resolv4K lens system offers a coaxial lighting module, with an 8mm input ferrule that will directly accept the Advanced Illumination SL162 coax/spot light. The SL162 coaxial spot light is available in white and in monochromatic wavelengths from 365nm to 940nm. It is compatible with the Advanced Illumination inline and external light controllers for intensity, strobe, overdrive, and gate control.
The size of a wide field-of-view is relative. As an example, a standard resolution 5MP camera may be able to image a 5mm X 3.75mm area. By using a higher resolution camera and a lens that maintains the required lens resolving power over a larger field-of-view, a single high resolution image from a 24MP camera provides the equivalent field-of-view coverage of nearly 5 lower resolution images. Fewer images to capture means faster inspection cycle times and fewer motion steps to enhance machine throughput.
With a color vision platform using a single-sensor camera, it’s important to start with the highest total resolution possible. This is because, in simplest terms, not every camera pixel sees every color. There is a Bayer filter over the sensor in a mosaic of red, green, and blue filters arranged in a grid over the imager’s photosensors. The pattern is half green, one quarter red, and one quarter blue.
For reference, a 3-chip color camera provides a full image sensor for each R, G, and B channel, providing full sensor resolution for each color channel.
The Pixelink USB 3.0 PL-D7924 single-sensor color camera provides an image resolution of 24MP, with 5328 x 4608 pixels, a pixel pitch of 2.74μm x 2.74 μm, and a 1.2” format C-mount. This camera is available in board-level and enclosed configurations. White Balance functions are accessed through the Pixelink Capture software, included with every Pixelink camera.
The Navitar SingleShot™ Super Wide Field 4K Imaging Lens maintains its image resolving power across a larger field-of-view to take advantage of large format high resolution image sensors. The fewer discrete images required to fully image a sample, the higher the throughput of the inspection system. The SingleShot Lens combines the field-of-view of a macro lens with the resolution and high NA of a microscope objective, providing exceptional images for demanding industrial and life science applications. This is Navitar’s highest NA medium to high-magnification lens.
For this example, the lighting selected is an Advanced Illumination DF198 diffuse white LED ring light, providing an evenly illuminated image and the ability to move between bright and dark-field lighting effects by changing the working distance of the light to the subject. The diffuse light helps minimize specular reflections and is available in a range of diameters. For monochromatic imaging, the ring light is available in blue, green, and red wavelengths.
The Advanced Illumination DCS-100 and DCS-103 lighting controllers provide the ability to more fully control the lighting components when integrated into an online system. In some applications, the lighting will be continuously on and the external controller functions may not be required. These controllers enable regular and overdrive strobing to stop any motion and can provide 3X-6X the light intensity in overdrive mode. This is important when there’s movement of the part or the imaging system or motion settling to consider. The Pixelink camera provides a trigger output to properly time the image acquisition with the lighting pulse. The external lighting controllers provide Ethernet addressability, an SDK to better integrate the lighting control into an online inspection application, and full control of the light pulse and timing.
A key feature of the Pixelink PL-D757 camera is a Dual ADC mode, where each pixel can be read out with two different gains. The PL-D757 combines the Dual ADC images into a single hybrid HDR (High dynamic Range) image directly on-camera, removing the need for any host processing. Real-time on-camera HDR is an easy way for the user to gain 6-10dB of additional dynamic range on their image without straining the CPU or requiring additional complex software algorithms. HDR brings down the gain to see features in bright areas and brings up the gain on low-light areas to bring out previously unseen details in the real-time processed output image.
When configuring a color high-magnification imaging system for R&D and lab use, flexibility and performance over a wide range of application environments is essential for maximum usage. The high-level benefits of a video-based inspection system include 1) the ability to capture, store, and share images that make training more efficient and help establish shared standards for manufacturing quality, 2) the ability to reconfigure the modular imaging system by changing components, expanding capabilities while minimizing additional investment.
The Pixelink USB 3.0 PL-D757 color camera provides 7.1MP and 3208 X 2200 pixels. The pixels are 4.5µm X 4.5µm, which will result in improved apparent resolution of the viewed image over image sensors with small pixels, ideal for manual inspection images. This is a 1.1” format camera with a trigger input and strobe output, available in an enclosed or board-level configuration. The camera is also available in monochrome.
Navitar’s Resolv4K Zoom lens system provides high optical performance with a 7X zoom range and flexible working distance options. This is the same lens family as in Configuration 1, but with zoom lens capability.
As with every application, proper lighting is the basis for successful imaging. Since this is a general-purpose manual color inspection system, the selected light is a CCS LDR2-IU diffused ring light, available in multiple diameters and with a simple push button intensity controller built into the cable. Diffused ring lights provide softer light, reducing specular highlights. The diffuse ring lights also provide both bright-field and dark-field illumination effects based on the light height above the workpiece. This makes them flexible for manual inspection stations that may see a variety of objects and inspection requirements.
As noted in the linked datasheet, there are additional light configurations that include the simple push button intensity control, including ring lights, backlights, bar lights, dome lights, and square diffuse lights. For coaxial lighting, use the spotlight shown in Configuration 1. For more complex applications, R.J. Wilson, Inc. will discuss the lighting options available.
The Pixelink PL-D755 color or monochrome camera is a 2/3” format 5MP USB3.0 camera, providing 2448 X 2048 imaging pixels. This camera is a good match for the Zoom 7000-2 close-focusing zoom lens and provides crisp images for basic R&D and lab imaging or offline spot checks. USB3.0 connectivity makes it easy to integrate this simple inspection system on a desktop. The included Pixelink Capture software is used to view and save images.
The Navitar Zoom 7000-2 Macro Lens has a focal length range of 18.6-111mm (6X) and provides a close working distance of 125mm to infinity. This parfocal lens remains in-focus through the zoom range. With the camera highlighted and at a working distance of 127mm, this configuration will provide a field-of-view from 8.8mm X 6.6mm to 51mm X 38mm. At a working distance of 300mm, this configuration will provide a field-of-view from 24mm X 18mm to 141mm X 106mm.
The selected Effilux EFFI-RING light is known as the light to use when you don’t know what you need. The Effilux EFFI-RING is a larger LED ring light that provides the ability to change the window on the front of the ring light, selecting between transparent, semi-diffuse, and opaque windows to adjust the light’s dispersion. In addition, the ring light permits changing the beam angle of the lighting to permit fine-tuning of the illuminated region based on the working distance.
The EFFI-RING includes 2 inputs: an M12 with a built-in driver and an M8 with direct access to the LEDs for use with an external light controller. This configuration example is based on using the built-in driver. When using a monochrome imager, this light is available in 405nm, 465nm, 525nm, 625nm, and 850nm. A polarizer option is available to reduce glare.
Navitar offers mounting adapters and stands to hold the Resolv4K, SingleShot, and Zoom7000-2 lenses. Whether adapter plates are mounted in a microscope fixture, mounting adapters are fixtured to a flat surface, or a complete stand is required, models are available for each lens, as shown on the datasheets.
Included with every Pixelink camera, Pixelink Capture is a real-time, image preview and acquisition program included with all Pixelink cameras. Users have the ability to adjust all camera features, including white balance, region-of-interest, frame rate, exposure, gain, and color, through an easy to use GUI, prior to image or video clip capture.
The multi-window environment includes a preview window, a configuration window, and a real-time histogram, that can be displayed for up to four cameras at a time. The program also includes built-in measurement tools and autofocus applications (with appropriate hardware options).
A Software Development Kit is available for Linux or Windows. It includes a Corporate License & Lifetime Support. Providing full control of all camera functions, the Pixelink Software Development Kit (SDK) is the software package of choice for developers and system integrators who are integrating Pixelink cameras into their applications. The Pixelink SDK provides access to the full Pixelink Application Programming Interface (API) and provides sample applications, wrappers for many 3rd party controls, such as LabVIEW, along with full documentation.
This web page discusses a range of cameras, high-magnification modular lens systems, LED lighting, and simple image capture software. These components provide a flexible variety of components that can be configured into a wide range of machine-integrated, online, and R&D lab imaging systems. To schedule a Teams or other video call to discuss your application requirements in more detail, please contact R.J. Wilson, Inc. at [email protected] or at 781-335-5500.
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