How Polarization Image Sensors Work & 9 Machine Vision Applications Leveraging Sony’s On-Chip Polarization Technology

How Polarization Image Sensors Work & 9 Machine Vision Applications Leveraging Sony’s On-Chip Polarization TechnologySony polarization image sensors, like the IMX250MZR and the IMX250MYR camera sensors, offer great solutions for challenging machine vision applications. In low contrast and highly reflective imaging conditions, polarized sensors can reveal hidden material properties and defects that normal color and mono sensors can’t.

How Polarization Image Sensors Work

Polarization is a fundamental property of light. The polarization of light is the direction that the electric field of light oscillates. Most light sources, such as the sun, emit unpolarized light. Unpolarized light vibrates at randomly oriented directions perpendicular to the direction of travel.

To polarize light, those random vibrations are removed or transformed into a linear, circular, or elliptical electromagnetic wave. A polarization camera sensor filters and transforms unpolarized light into polarized light before recording the image.

The Sony polarization image sensor incorporates a layer of polarizers above the photodiodes. Four different angled polarizers are placed on each pixel. The pixel block/calculation unit detects the linear angles of polarized light and is able to record an image using the now polarized light.

Applications for Sony On-Chip Polarization Image Sensors

There are a number of machine vision applications ideal for Sony’s on-chip polarization image sensor technology. Here are a few common applications leveraging the power of Sony’s on-chip polarization capabilities:

Glass Inspection. On-chip polarization is used for the inspection of glass products to detect stress or scratches. By measuring the angles of refracted light, deformities are easily uncovered that would otherwise go unnoticed. 

Aerospace Metal Component Marking. Metal components are labeled with braille-like markings. Machine vision systems with Sony’s on-chip polarization image sensors are used to read these markings for part traceability and identification. 

Recycling Plastics and Glass. Sorting plastics and glass is notoriously difficult, as they may appear similar but have different chemical compositions. Sony’s on-chip polarization technology helps sort plastics and glass more accurately for more profitable recycling services.  

Automotive Inspection.Many components in the automotive sector are reflective or transparent, namely steel and glass. Sony’s polarization image sensors allow machine vision systems to filter out glare and detect refracted angles of light to provide better inspections for safer products. 

Drone Surveillance. Sony’s polarization image technology facilitates a camera’s capabilities for differentiating camouflaged or hidden objects from the surrounding background. For drone surveillance applications, polarization improves visibility beyond monochrome or color machine vision systems. 

Pharmaceutical Inspection. Blister packs, glass vials, and other pharmaceutical packaging can create glare and reflection. On-chip polarization effectively filters out this glare for more accurate inspection of medicine and the packaging itself.

Food Packaging Inspection. Food packaging is often highly reflective or transparent, creating inspection difficulties for conventional machine vision systems. Vision systems featuring Sony’s on-chip polarization sensor technology filter out the reflected light and detect the angles of refracted light to automate inspection of food packaging.   

Semiconductor Inspection. During the manufacture of semiconductors, each semiconductor takes a chemical bath. Inspection must occur during this bath for quality assurance, but the environment is highly reflective.  Sony’s on-chip polarization quickly eliminates this reflection for accurate inspection.

LCD Display Inspection.LCD display inspection requires significant filtering of unwanted angles of light. On-chip polarization technology allows for accurate filtering of unwanted light and quick changeover to filter other angles and wavelengths.

Download our free ebook: On-Chip Polarization: A Better Way to Polarize Light in Machine Vision Applications to learn about Sony’s on-chip polarization technology for machine vision applications.

Contact Phase 1 Technology to ask about the polarization image sensor options for the 10 Gigabit GigE Emergent Vision Technologies HR-5000-S camera.