1stVision, Author at 1stVision Inc. - Machine Vision Articles

July 24, 2026July 24, 2026

RGB / NIR applications with DALSA Linea Multispectral

Multispectral imaging, in general terms, creates solutions that draw on spectral response from two or more regions of the electromagnetic spectrum. So it might be UV+VIS or VIS+IR, for example. And VIS might be monochrome (with or without filters) or color. And IR might be any of NIR, SWIR, MWIR, or LWIR. If you can add value and competitive advantage through an application built on a multispectral approach, there are cameras, sensors, lenses, filters, and lighting to support your design.

Traditionally one would need two different cameras to create a multispectral solution. That’s because most cameras are designed around a sensor that is optimized for just one portion of the spectrum. While there are good reasons behind cameras that “specialize” on just a segment of the spectrum, it creates multi-camera integration challenges for those who want to build multispectral solutions. Until now…

RGB / NIR with DALSA Linea ML-FC-08K07N

Take a look at the response curve below. The 8K DALSA proprietary CMOS sensor used in the Linea ML-FC-08K07N camera performs well on both sides of 700 nm. To the left it’s responsive in the VIS portion of the spectrum, from 400 – 700 nm. And to the right it does well in NIR, from 800 – 1000 nm. That’s an unusual and powerful range.

Applications potential

Banknote and secure documents inspection: The visible inspection handles geometric feature checks, while NIR looks for special inks that appear only in those wavelengths.

Semiconductor wafer and PCB inspection: Find defects below the surface with NIR. While doing surface inspection in VIS.

Multisource imaging

Suppose you need to capture both brightfield and darkfield images of the same linescan continuous target. While one could set up two different cameras, calculate offset timing based on motion characteristics, and integrate or compare images on the host…

… with multiple strobed light sources… and the DALSA ML 8K camera sensitive to both VIS and NIR, the same camera can capture both brightfield and darkfield images in a single pass.

Courtesy Teledyne DALSA

Key features include:

8,192×4 multiline trilinear color & NIR CMOS line scan sensor

Camera Link HS Fiber interface*

75kHz scan rate

72dB dynamic range

(*) Linea ML is DALSA’s first camera with native fiber optic connectors. No adapters or converters required. Fiber has two key advantages: (1) long cable runs beyond copper cable performance; (2) immunity to electrical interference

CLHS native fiber interface – Courtesy Teledyne DALSA

Linea Multispectral Line scan – Courtesy Teledyne DALSA

Line scan and multispectral imaging are both a bit more obscure than area scan machine vision. But each incredibly powerful, either alone or in combination. We’d be delighted to understand your application goals and constraints, to help you determine solution options.

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.

#Multispectral

#LineaML

July 6, 2026July 6, 2026

How to eliminate glare in machine vision systems

Machine vision – indeed human vision too – relies heavily on contrast. The feature(s) being identified need to stand out against any competing candidate features. Otherwise confusion is present. Which means vision either doesn’t work, or isn’t efficient.

While it’s easy to achieve good contrast in certain machine vision applications, sometimes we’re presented with the special challenges of glare. The target object is the same, in the two images below. If the goal is to read the alphanumeric information, which image would you rather pass to your machine vision software?

Techniques to eliminate glare

Glare can arise due to highly reflective surfaces, especially in combination with the direction of the light source relative to the lens and sensor capturing the image. Thankfully there are a number of techniques to eliminate or substantially reduce glare.

Off-axis lighting

For the 1-D bar code reading application illustrated below, moving the light to an off-axis position creates dark field orientation, eliminating the glare. Identical materials but different geometry does the trick!

a. Lighting diagram; b. High-angle light reflects from specular surface; c. Off-axis light improves the image; Courtesy Advanced Illumination

Diverse lights and geometries

Consider another example. In this case we have a titration tray, with multiple wells. Each well has a laser-etched 2-D code.

Analysis/discussion below. Courtesy Advanced Illumination

(a) the titration tray at low resolution, marked up with red outline around 6 wells isolated in high resolution images (b) – (f)
(b) High-angle ring light
(c) Coaxial light
(d) Dark field ring light
(e) Diffuse dome light
(f) Flat diffuse light

In this scenario, both (d) the dark field ring light, and (f) the flat diffuse light, are far superior to the other options, and the flat diffuse light is the winner.

Flat diffuse light function diagram – light is directed downward, and more off-axis than a coaxial illuminator, yet less off-axis contribution than a dome light. Courtesy Advanced Illumination

NOTE: The example above is NOT meant to suggest that flat diffuse light is always the winner. It’s important to understand the characteristics of the surface you are inspecting, and each candidate type of lighting, and the geometric options. And to test!

Guideline

The following diagram is a general guideline, based upon the two most prevalent surface characteristics: (1) Surface flatness and texture, and (2) Surface reflectivity profile

Guide to likely “best approach” based on prevalent surface characteristics – Courtesy Advanced Illumination

Send your samples

Lighting is a complex topic, so we’re happy to help. If you are uncertain which light type to choose and how to configure, we may be able to do some testing for you. Contact us to arrange sending samples to test in our lab, and we can recommend sensor, lensing, lighting, and configuration options.

For comprehensive coverage on glare reduction – and more – download A Practical Guide to Machine Vision lighting from our knowledge base.

#glare

#contrast

#machinevisionlighting

#diffuser

#polariser

July 6, 2026July 6, 2026

KOWA Innovations: New LF Large Format ruggedized lenses

Kowa LF high-resolution large-format machine vision lenses are engineered for rigorous industrial imaging. With a 46.0mm image circle, these optics are optimized for 4K line scan cameras and large-sensor area scan systems.

Rugged large format lenses – Courtesy Kowa

Two mount options

F-mount or TFL-II mount

Large image circle options up to approximately 43.3mm to 46mm depending on model.
For sensors with pixel sizes from 7.5µm on LF line scan models and 3.1µm on CLS color line scan model.
Very low distortion for web, print, packaging and materials inspection
Manual focus and iris control.

Noteworthy features

Anti-Rattle F-Mount: Ensures the lens stays locked in place to eliminate image shake in vibration-prone installations.

Enhanced Thumb-Screw Retention: Specialized slide mechanisms prevent thumb screws from working loose, yet allow swift lens removal or changeout as needed.

4K-Ready Optics, Multiple Focal Lengths: Designed for 4K line scan and high-resolution imaging, the LF Series is available in 28 mm, 35 mm, and 50 mm focal lengths for a range of applications.

Industrial reliability: The new ruggedized LF prototypes set a new standard for stability and service life, delivering secure imaging performance under the most demanding circumstances.

Lens selection

If you are a seasoned imaging professional, you may know exactly how to choose the optimal lens, from the large range of available lenses.

Or you may prefer a guided approach.

Or a hybrid approach, using your own review of key considerations in machine vision lens selection, together with our guidance.

#Largeformat

#F-mount

#TFL-II

July 6, 2026July 6, 2026

What is TDI? Time Delay Integration?

TDI is based on the concept of accumulating multiple exposures of the same (moving) object, effectively increasing the integration time available to collect incident light. The object motion must be synchronized with the exposures to ensure a crisp image.

Line scan sensors are available for diverse applications – Courtesy Teledyne DALSA

Context

If an object were stationary, and one wasn’t in a hurry, one could just do a longer exposure in order to achieve an ideally saturated image. But the object in question is in fact moving. And it’s a line scan application. Each line exposure is extremely fast, so there’s not much opportunity to accumulate sufficient light into the sensor.

Candidate solutions

Use “faster” sensor that is more sensitive in low light situations? Conceptually plausible but not always available relative to speed of motion and available light.

Introduce artificial light? Usually one already adds concentrated light with line scan, but for challenging applications it may not be sufficient… relative to the speeds one hopes to attain.

Use Time Delay Integration (TDI) to build up final image as composite from multiple exposures carefully synchronized to object’s motion. Key concept: the object is moving anyway, so take advantage of that movement as an opportunity to get multiple “looks” at the same slice of the object. A variation on “when given lemons make lemonade”.

See the video below for an illustrative simulation. The conceptual application is mail processing, where the goal is to read whether a letter is stamped, with which denomination of postage, all while the letter is moving at continuous speed along a conveyor belt, lit only by ambient or low intensity light.

Courtesy Teledyne DALSA

The memory summing of the successive exposures builds the readout image.

Benefits

Speed: You can increase the speed of the target object or inspection web, improving overall throughput. This alone may be a huge competitive advantage.

Lower lighting costs: Get by with just one instead of two lights, and perhaps just a modest light rather than a high-intensity one.

Signal to noise ratio: SNR is improved. Since multiple exposures are summed, useful image signal increases while random noise is reduced. This gives cleaner images and better defect detection.

Tradeoffs

Clearly sufficient synchronization must be achieved for TDI to work effectively. Thankfully the synchronization doesn’t have to be perfect – a TDI device can comfortably tolerate a 2-4% velocity mismatch between inspection web and imager. This is not difficult to achieve using a web-mounted encoder to supply a sync signal to the camera, even with webs that change speed. There are thousands of successful implementations.

For a wide range of line scan products, the the Teledyne DALSA Linea families. For TDI in particular, drill in on the Linea HS and Linea HS2 products.

Applications

Typical applications include, but are not limited to:

Semiconductor wafer inspection
High-density interconnect inspection
Quality control on flat panel displays
Some life science applications

In a nutshell, if it’s “light starved” and line scan, TDI can be the answer.

#Timedelayintegration

#TDI

#Linescan