Category: Line Scan

Product innovation continues to serve machine vision customers well. Clever designs are built for evolving customer demands and new markets, supported by electronics miniaturization and speed. Long a market leader in line scan imaging, Teledyne DALSA now offers the Linea HS2 TDI line scan camera family.

Video overview

The video below is just over one minute in duration, and provides a nice overview:

Backside illumination enhances quantum efficiency

Early sensors were all used frontside illumination, and everybody lived with that until about 10 years ago when backside illumination was innovated and refined. The key insight was to let the photons hit the light-sensitive surface first, with the sensor’s wiring layer on the other side. This greatly improves quantum efficiency, as seen in the graph below:

Applications

This camera series is designed for high-speed imaging in light staved conditions. Applications include but are not limited to inspecting flat panel displays, semiconductor wafers, high density interconnects, and diverse life science uses.

Line scan cameras

You may already be a user of line scan cameras. If you are new to that branch of machine vision, compare and contrast line scan vs. area scan imaging. If you want the concept in a phrase or two, think “slice” or line of pixels obtained as the continuous wide target is passed beneath the camera. Repeat indefinitely. Can be used to monitor quality, detect defects, and/or tune controls.

Time Delay Integration (TDI)

Perhaps you even use Time Delay Integration (TDI) technology already. TDI builds on top of “simple” line scan by tracking how a pixel appears across several successive time slices, turning motion blur into an asset through hardware or software averaging and analysis.

Maybe you already have one or more of Teledyne DALSA’s prior-generation Linea HS line scan cameras. They feature the same pixel size, optics, and cables as the new Linea HS2 series. With a 2.5x speed increase the Linea HS2 provides a seamless upgrade. The Linea HS2 offers an optional cooling accessory to enhance thermal stability.

Frame grabber

The Linea HS2 utilizes Camera Link High Speed (CLHS) to match the camera’s data output rate with an interface that can keep up. Teledyne DALSA manufactures not just the camera, but also the Xtium2-CL MX4 Camera Link Frame Grabber.

The Xtium2-CL MX4 is built on next generation CLHS technology and features:

• 16 Gigapixels per second
• dual CLHS CX4 connectors
• drives active optical cables
• supports parallel data processing in up to 12 PCs
• allows cable lengths over 100 meters with complete EMI immunity

Which camera to choose?

As this blog is released, the Linea HS2, with 16k/5μm resolution provides an industry leading maximum line rate of 1 MHz, or 16 Gigapixels per second data throughput. Do you need the speed and sensitivity of this camera? Or is one of the “kid brother” models enough – they are already highly performant before the new kid came along. We can help you sort out the specifications according to your application requirements.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera and components selection.  With a large portfolio of cameras, lenses, cables, NIC cards and industrial computers, we can provide a full vision solution!

About you: We want to hear from you!  We’ve built our brand on our know-how and like to educate the marketplace on imaging technology topics…  What would you like to hear about?… Drop a line to info@1stvision.com with what topics you’d like to know more about

As anticipated when Teledyne DALDA’s AxCIS Line Scan Series was introduced a few months ago, color models have now been released. The “CIS” in the product name stands for Contact Image Sensor. In fact a CIS doesn’t actually contact the object being imaged – but it’s so close to touching that the term has become vision industry jargon to help us orient to the category.

What can CIS do for me?

Think “specialized line scan”. Line scan in that it’s a linear array of sensors (vs. and area scan camera), requiring motion to create each successive next slice. And “specialized” in that CIS is positioned very close to the target, Plus low power requirements. And excellent price-performance characteristics.

Why is the new color offering interesting?

Just as with area scan imaging, if the application can be solved with monochrome sensors, that’s often preferred – since monochrome sensors, lensing, and lighting are simpler. If one just needs edge detection and contrast achievable with monochrome – stay monochrome! BUT sometimes color is the sole differentiator for an application, so the addition of color members to the AxCIS family can be a game changer.

Why Teledyne DALSA AxCIS in particular?

A longtime leader in line scan imaging, Teledyne DALSA introduces the AxCIS series in 2023 and continues to release new models and features. Vision Systems Design named the AxCIS family of high-speed high-resolution integrated imaging modules with their 2024 Gold Honoree Award.

AxCIS Series Key Attributes

• Compact modules integrating sensors, lenses and lights
• Option to customize the integrated lighting for specific CRI to aid in color measurement.
• Current width choices 400mm (16 inches) or 800mm (32 inches)
• Customizable lengths coming, in addition to the 400mm and 800mm models
• CIS covers entire FOV – without missing any pixels and without using interpolation, allowing for accurate measurements. The competition has gaps between sensors causing areas which are not imaged and inability to measure properly
• Selectable pixel sizes up to 900dpi
• Gradient index lenses are used so there is no parallax and essentially telecentric.  (Great for gauging applications)  
• Binning support, summed to provide brighter images
• 4 available AOIs
• CameraLink HS interface
• Up to 120 kHz line rates … and cables lengths to 300m
• No alignment or calibration required – lighting and sensors are pre-aligned
• HDR imaging with dual exposure mode

Get quote

See specs for specific models in the Teledyne DALSA AxCIS Series.

HDR – a closer look

By using two adjacent rows of sensors, one row may be used for a short exposure to capture the rapidly saturated portions of an image. A second row of sensors can take a longer exposure, creating nuanced pixel values of areas that would otherwise have been undersaturated. Then the values are combined to a composite image with a wider dynamic range with more useful information to be interpreted by the processing algorithms.

Applications

While not limited to the following, popular applications include:

Want to see other Teledyne DALSA imaging products?

Teledyne DALSA is long-recognized as a leader and innovator across the diverse range of imaging products – click here to see all Teledyne DALSA products.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera and components selection.  With a large portfolio of cameras, lenses, cables, NIC cards and industrial computers, we can provide a full vision solution!

About you: We want to hear from you!  We’ve built our brand on our know-how and like to educate the marketplace on imaging technology topics…  What would you like to hear about?… Drop a line to info@1stvision.com with what topics you’d like to know more about. 

Teledyne DALSA has released the AxCIS 800mm mono/HDR, and the AxCIS 400mm mono, the first two members of a new flexible and scalable product family of Contact Image Sensors (CIS). As other members are released, users can choose fields of view (FoV) in 100mm increments, e.g. 400mm, 500mm, 600mm, 700mm, and 800mm.

Contact Image Sensor vs. Linescan

Actually that’s a trick heading! A contact image sensor (CIS) is a type of linescan camera. Conventionally, the industry calls it a linescan camera if the sensor uses CMOS or CCD. while it’s called a CIS if it bundles a linear array of detectors, lenses, and lights.

But CIS is very much a linescan type of camera, With a 2D area scan camera, a comprehensive pixel array captures hundreds or thousands of (X,Y) values in a single exposure. But a Contact Image Sensor requires either the target or the imaging unit to move, as a single exposure is a slice of Y values at a given coordinate X. Motion is required to step across the set of X values.

Two more notes:

1. The set of X values may be effectively infinite, as with “web inspection” applications
2. The term “contact” in CIS is a bit of a misnomer. The sensor array is in fact “very close” to the surface, which must thereby be essentially flat in order to sustain collision-free motion. But it doesn’t actually touch.

AxCIS key attributes include:

• 28um pixel size (900dpi)
• high speed 120KHz using Camera Link HS
• HDR imaging with dual exposure mode
• optional LED lighting
• fiberoptic cables immune to EMI radiation

Application areas share the characteristics of flat surfaces and motion of either the target or the sensor, since contact image sensing (CIS) is a form of linescan imaging.

HDR imaging

Some targets are inherently challenging to obtain sufficient saturation for the darker regions while avoiding over-saturation for the lighter areas. The multiline sensors used in AxCIS utilize a sensor array with:

• One row of the sensor array that can have a longer exposure for dark scenes
• Another row using a shorter exposure for light scenes

The camera then combines the images, as shown below. The technique is referred to as High Dynamic Range imaging – HDR.

Want to know more about area scan vs line scan? And multifield line scan? And other Teledyne DALSA linescan products, in which they have years of expertise? See our blog “What can multifield linescan imaging do for me?“.

For details on the AxCIS CIS family, please see the product page with detailed specs.

If you’ve had enough reading, and want to speak with a real live engineer, just call us at 978-474-0044.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera and components selection.  With a large portfolio of lenses, cables, NIC cards and industrial computers, we can provide a full vision solution!

While the differences between the applications for an area scan machine vision camera vs. a line scan camera may often appear to be subtle, the differences in their technologies and the ways to optimize them in specific use cases is clear. By optimizing we include relative costs as well as imaging outcomes.  This brief overview provides a foundational overview. For additional application engineering assistance please contact one of our industrial imaging technical consultants and get the support you need.

Definition of an Area Scan Camera:

Area scan cameras are generally considered to be the all-purpose imaging solution as they use a straight-forward matrix of pixels to capture an image of an object, event, or scene. In comparison to line scan cameras, they offer easier setup and alignment. For stationary or slow moving objects, suitable lighting together with a moderate shutter speed can produce excellent images.

Even moving objects can become “stationary” from the perspective of an area scan camera through appropriate strobe lighting and/or a fast shutter speed, so just because something is motion does not necessarily disqualify an area scan solution.

Among the key features of an area scan camera include that the camera, when matched with a suitable lens, provide a fixed resolution. This allows for easy set up in imaging system applications where the cameras will not move after installation. Area scan cameras are also extremely flexible, as a single frame can be segmented into multiple regions-of-interest (ROI) to look for specific objects rather than having to process the entire image.

Additionally, some models of area scan cameras are optimized to be sensitive to infrared light, in portions of the spectrum not visible to the human eye. This allow for thermal imaging as well as feature identification applications that can be innovative and cost-effective, opening new opportunities for machine vision.

Definition of a Line Scan Camera:

In contrast to an area scan camera, in a line scan camera a single row of pixels is used to capture data very quickly. As the object moves past the camera, the complete image is pieced together in the software line-by-line and pixel-by-pixel.

Line scan camera systems are the recognized standard for high-speed processing of fast-moving “continuous”objects such as in web inspection of paper, plastic film, and related applications.. Among the key factors impacting their adoption in these systems is that the single row of pixels produced by line scanning allows the imaging processing system to build continuous images unlimited by a specific vertical resolution. This results in superior, high resolution images. Unlike area scan cameras, a line scan camera can also expose a new image while the previous image is still transferring its data. (Because the pixel readout is faster than the camera exposure.) When building a composite image, the line scan camera can either move over an object or have moving objects presented to it. Coordination of production/camera motion and image acquisition timing are critical for line scan cameras but, unlike area scan cameras, lighting is relatively simple.

What if you need to image a medical tube, or round object, such as a steel ball bearing?

In certain applications, line scan cameras have other specific advantages over area scan cameras. Consider this application scenario: You need to inspect several round or cylindrical parts and your typical system experience is with area scan cameras, so you set about to use multiple cameras to cover the entire part surface. It’s doable, but a better solution would be to rotate the part in front of a single line scan camera to capture the entire surface and allow the processor to “unwrap” the image pixel-by-pixel. Line scan cameras are also typically smaller than area scan. As a result, they sneak into tight spaces such as in a spot where they might have to peek through rollers on a conveyor to view a key angle of a part for quality assurance.

Not sure which area scan or line scan camera is right for you?

There are a host of options and tradeoffs to consider even after you’ve made your decision on the technology that’s likely best for you. 1^st Vision is the US distributor you need. Our industrial imaging consultants are available to help you navigate the various camera models and brands from industry-leading manufacturers Teledyne DALSA, IDS, and Allied Vision.

Contact us to learn more.