Dalsa Nano M2450 polarized camera: Resolving defects that are undetectable with traditional imaging!

Dalsa Polarization camera

Genie Nano cameraThe first Genie Nano camera model with a quad-polarizer filter using the Sony Pregius IMX250-MZR 5.1MP monochrome image sensor is now available.  The Teledyne Dalsa Nano M2450 camera incorporates the nanowire polarizer filter allowing detection of both the angle and amount of polarized light.

What problems can the Nano M2450 polarized camera solve?

Polarized filtering can reduce the effects of reflections and glare from multiple directions and reveal otherwise undetectable features in the target scene.  Polarization enables detection of stress, birefringence, through-reflection and glare from surfaces like glass, plastic, and metal.  Sony’s newest image sensor, with its pixel-level polarizer structure, enables the detection of both the amount and angle of polarized light across a scene. Dalsa Nano polarization camera

 

 

 

 

Four different angled polarizers (90°, 45°, 135° and 0°) are positioned on each pixel, and every block of four pixels comprises a calculation unit.Contact 1st vision for pricing

How does polarization work?  Theory of operation

Polarization direction is defined as the electrical direction.  Light, with its electrical field oscillating perpendicular to the nano wire grid, passes through the filter while that in the parallel direction is rejected.

For Polarized light, only the portion of the light vector perpendicular to the angle of the nanowire filter grid passes.

polarization filter

For example, with a wire-grid polarizer filter at 90 deg. to the maximum transmission is for polarized light at an angle of 0 deg.

polarizer filterThe polarizer filter is placed directly on the sensor’s pixel array, beneath the micro-lens array.  This design, compared to polarize filters on top of the micro lens array reduced the possibility of light at a polarized angle being misdirected into adjacent pixels (cross talk) and incorrectly detected at the wrong angle.

Dalsa polarizer filter theory

The Genie Nano’s polarizer filter on the camera sensor is a 2 x 2 pattern, with each pixel having a nanowire polarizer filter with different angles (90, 45, 135 and 0 degree’s)

The image output pattern of the monochrome camera is arranged in 2 x 2 pixel block as follows:

Pixel blocks

 

 

 

 

That is, the first line output is an alternating sequence of pixels 0 & 35 degrees, with the following line of 45 and 90 degrees.

Given the proportion of light available through these four filters, any angle of polarized light can be calculated. Any given state of polarization can be composed by two linearly polarized waves in perpendicular directions. The state of polarization is determined by the relative amplitude and difference in phase between the two component waves.

Calculations on the 2×2 filter blocks result in a single pixel for each polarizer filter angle, therefore the resulting image is one fourth the original image resolution. For example, with an original image of 2464×2056, the resulting image is 1232×1028 (original buffer width/2 and original buffer height/2) for a single polarizing angle.

resulting image

Teledyne Dalsa offers a Polarization demo user interface making it easy to test the polarization techniques for various applications.  This includes the ability to see the results of various processing algorithms with the summed images.

Dalsa Polarization demo
As part of the demo program, images can be displayed with pseudo-color mapping

In summary, the new Dalsa Nano M2450 polarized camera can help resolve defects not detected by traditional imaging!   Contact 1st Vision to arrange a camera demo in which we will provide the demo polarization software as well or discuss your application.  Or click HERE to request a quoteContact us

 

 

Need line scan?  – With the addition of the Genie Nano polarized model, Teledyne DALSA is the first company to offer polarization for both area and line scan (Piranha™4 polarization) cameras

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

Related Posts

Dalsa line scan polarization camera makes invisible visible!

Teledyne Dalsa TurboDrive 2.0 breaks past GigE limits now with 6 levels of compression

The Machine Vision camera “Sleepability factor”!?

machine vision camera

sleepy cameraThe sleepability factor, or how saving $50 on a machine vision camera could cost you thousands!

As an independent machine vision camera distributor, we are asked about the manufacturers we represent.  Out of all them, we have chosen to only carry products from a few machine vision camera and lens companies of which we have not really changed this over the 20 years we have been in business.  Why is this?

These days, there are probably over 30 different camera manufacturers making products for the machine vision marketplace, many using the identical image sensors.  Considering anyone can just put up a web page and start selling, how can a user know which product to purchase?  Are there really any differences?  Should I just purchase on price?  Should I buy from a distributor or from the manufacturer direct?  All great questions, that we will attempt to answer.

The very simple and quick answer is that if you just need to get a image in good light, pretty much any camera from any vendor will do that job.  No matter if it is from a large company or a 2 person startup, when you take the product out of the box, you should see a “good” image.

But if you said, “I want this camera to run 24/7 for the next 5 years, I want to be able to develop complex software to integrate into my machine, I need the image sensor plane to be within a certain tolerance for each machine,” this changes the situation.

IDS imaging camera
IDS Imaging USB3 cameras

The reason we have chosen the camera manufacturers we sell products from is because each of them has a proven track record of reliability.  Each of the companies we represent ships 6 figures of cameras per year.  IDS Imaging for instance ships close to 200,000 cameras per year and has a return rate of under 0.3%.

 

Allied vision camera
Allied Vision GigE Cameras

Allied Vision was the first company to incorporate the Precision Timing Protocol (PTP) which allows for precise multi camera sync, enabling our clients to not only make sure the application will work, but it doesn’t take years to develop it.

 

 

 

Dalsa line scan cameras
Teledyne Dalsa Line Scan cameras

 

Teledyne Dalsa, besides being a leader in line scan technology,  has a SDK that has been built upon for over 30 years.

 

 

JAI’s prism technology is so good that its competitors actually have JAI

JAI cameras
JAI 3-CMOS Prism camera

manufacture for them.  This isn’t to say there aren’t other camera companies with such characteristics.  There are, and many of the other camera companies have excellent products as well.  It is just that we have chosen these companies, and we have stood with them for 15+ years for good reasons… sleepabilty!

What does this mean to you as a client?  Yes, you can purchase a camera from any vendor, which on a $500 camera, you might even be saving $50 a camera.  If you purchase 100 cameras a year, this adds up to a reasonable savings of $5,000.  But what happens if your machine, which you sell globally, has a camera that fails.  What is the cost of the line going down at your client?  How do you look in your client’s eyes?  What is the cost for you to fix it?

If you had your choice of buying a camera with the same characteristics at roughly the same price, but one company makes 20,000 a year, and the other makes 200,000 a year, which would you choose?  The same is true if you can choose between a company that has offices all over the world, or just in one country.  Or one that has many application engineers to answer your questions, or just one.

We just want to point out that if you are making a purchase on price alone, depending upon your circumstances, it might not really be a savings at all.  In fact, it might actually not only be costing you money, but it might even be costing you your sleep!

Contact us

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

 

Dalsa line scan polarization camera makes invisible visible!

Teledyne Dalsa has released the first line scan polarization camera for machine vision.  The Piranha4 polarization camera provides the capability of detecting , stress, surface roughness,  birefringence and physical properties undetectable with conventional imaging making the invisible visible!

This unique technique uses four polarization channels with a color line scan camera solving various applications, but not limited to the following:

Glass Inspection:  Glass bottles, architectural glass sheets, and automobile windshields, etc. – Enables inspection of internal stress and defects non-visible with conventional imaging

Dalsa Polorized ruler

Film inspection: transparent films, packaging films, and patterned films etc. – Detect scratches, digs, and other surface defects that are difficult to detect with conventional imaging   Dalsa Polarized scratch

Precision optics: optical lens, prisms, fibers, and micro-optical – Detect residual internal stress and thermal annealing effects
polarized - stress in sun glasses

Flat Panel Display and PCB inspection: Thin film transistors, organic LEDs, printed circuit boards etc.- inspect ITO, dust particles, films thickness, and surface defects with enhanced contrast

Carbon fibers: effectively inspect the quality of composite materials that are widely used in aircraft, aerospace, wind energy, and automotive industry

Food and material sorting: Increase sorting accuracy and detecting capability of foreign materials such as plastics, glasses, metals etc. with polarization imaging

Bio-medicine: digital pathology, in vitro cells culture, optical coherence tomography etc.- Provides additional information in birefringence tissues
Remote sensing: helps identifying special objects from natural background
And many more…

Contact 1st vision

Line scan polarization camera Features

  • CMOS Quadlinear sensor  – 2048 pixels
  • High speed line rate of 70k hz with 14.08 um pixels
  • Camera Link interface
  • Three polarization states plus and unfiltered channel (Output format with 0 deg (S component), 90 deg (P component), 135 deg and unfiltered polarization states.)

Full specifications on the Teledyne Dalsa polarization camera ( P4-CP-02K07Q-00-R ) can be found HERE

line scan camera Polarization angles

White Paper  – Learn about this unique polarization technique with line scan cameras!   This white paper covers the following topics

  • How polarization techniques work in transmission and reflectance configuration
  • Comparison of three polarization filter technologies
  • How the sensor architecture is configured for polarization effects and visualization of defects.

line scan polarization camera white paper

1stVision has a strong working knowledge of polarization techniques, line scan cameras and lighting and can discuss your application in detail.

Contact us to talk to an expert!

Related Blog posts:
Teledyne Dalsa release of low cost GigE and camera link color line scan cameras

Video Tutorial:  How to setup HDR Imaging in Teledyne Dalsa Linea Line scan cameras

Teledyne Dalsa TurboDrive 2.0 breaks past GigE limits now with 6 levels of compression

Teledyne Dalsa Turbodrive

Teledyne Dalsa introduces TurboDrive 2.0 for their Genie Nanos

Dalsa Innovator awardWith the introduction of the Genie Nano came Turbodrive which allowed ‘faster GigE than GigE’ speeds. Turbodrive is a lossless hardware encoding scheme that potentially reduces the amount of data to be transmitted from the camera to the computer.  Dalsa’s Nanos, which are priced identical to the competition, offers the users the ability to go faster at no extra cost.  Note that the user can turn on or off the encoding.

However, the encoding scheme is data content dependent, and therefore if your data varies a lot within an image the compression is minimal.  If your data varies a lot from image to image, then using the encoding means that only certain frames will get a speedup resulting in an inconsistent data transfer rate.

Teledyne Dalsa Nano camera

Teledyne Dalsa has just recently introduced TurboDrive 2.0, a firmware upgrade for all Nanos. The major enhancement is that now TurboDrive offers multiple levels of encoding.  Level 0 is lossless, and each successive level has some potential lossy amount.

The table below indicates quality level,  image compression ratio (absolute worst case scenario)  and effective bandwidth gain

As you can see, at level 6, you have a worst case compression of 0.33, yet a speed up of 3.  Note, this is a worst case situation so you might get a speed up of 3x, yet be at 0.8.  The algorithm is data dependent!  (more about this in the tech primer)

Depending on the application, various compression levels provide minimal degradation.  The following images are shown for comparisons using the varying quality levels.

As you can see, even at level 4, there is very little degradation in the image.  It is easy to imagine that with this image, you can still do your image processing yet get a speed up of 68%!

Dalsa Nano Raw Image
Raw Image

Level 0 “Lossless” to Level 6 indicate the quality level in the images.

Dalsa Nano Turbodrive quality level comparisons
Quality level comparisons

Learn more by clicking the icon below for the comprehensive application note!

Teledyne Dalsa Turbodrive application note
To learn more about Teledyne Dalsa TurboDrive 2.0, please download the application note for full details.

1stVision has a ton of resources to learn about TurboDrive technology in general.  Please visit our dedicated Teledyne Dalsa Turbo Drive resource page HERE  

Contact 1st Vision

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How do you get the most pixels for your money? Check out the new Dalsa Nano C4900 camera!

Teledyne Dalsa Nano XL-M4090 cameras – 16MP cameras are now faster, cheaper and smaller!

Teledyne Dalsa Nano XL-M5100 cameras providing 25MP resolution for < $6K!