Calibration targets reduce unwanted reflections

MAY 19, 2009--Unwanted reflections from the surface of a calibration target cause problems in many optical calibration configurations. A method to reduce unwanted reflections is to use a calibration target with a white scattering surface. Due to light scattering caused by the surface roughness, no direct reflections occur. As an alternative to costly substrates such as ceramic substrates, a cost-effective method for the manufacture of the scattering surface has been developed. Cost reduction is primarily achieved by applying a white surface on standard glass substrates. The scattering surface show a uniform light distribution (quasi Lambertian scatter shape). The combination of a high-end patterning process for metal layers and the quality of the white surface produce an optical calibration target with good edge acuity and high pitch accuracy. Typical applications are 2-D calibration, reference marking of large objects, and photogrammetry.
IMT Masken und Teilungen
Greifensee, Switzerland
www.imtag.ch

For related information, visit the Lighting & Optics topic center.

-- Posted by Carrie Meadows, Vision Systems Design, www.vision-systems.com

------

PRESS RELEASE

Reflexion free optical calibration targets
Unwanted reflections from the surface of a calibration target cause problems in many optical calibra-tion configurations. The specular reflexion of the illumination light source causes a strong distortion in light intensity measurements. Vision systems have difficulty coping with this effect.

An efficient method to reduce the unwanted reflections is to use a calibration target with a white scattering surface. Due to the light scattering caused by the surface roughness, no direct reflections occur.

As an alternative to the hitherto used costly substrates used for this purpose (e.g. ceramic sub-strates), a novel, cost-effective method for the manufacture of the scattering surface has been de-veloped by IMT. The costs reduction is primarily achieved by applying the white surface on standard glass substrates.
The scattering surface show a uniform light distribution (quasi Lambertian scatter shape)

The combination of IMT's high-end patterning process for metal layers in combination with the quality of the white surface enable maintaining the quality and accuracy required for a high-end optical calibration target, e.g. good edge acuity and high pitch accuracy at a very competitive price.

Typical applications are 2D calibration, reference marking of large objects and photogrammetry.

Webcasts

Tips and techniques for improving OCR/OCV

Optical character recognition (OCR) and optical character verification (OCV) technologies offer many advantages in automation applications. They also involve some inherent challenges, which this we...

Making accurate measurements with machine vision software

In this webcast viewers will learn how to use machine vision to solve metrology tasks in factory automation and offline inspection applications. We will show how to choose the proper calibration an...

Choosing components for intelligent transportation systems

Intelligent transportation systems depend on the interoperation of sophisticated OEM components. This expert webcast will provide guidance on how to choose such components—including illumination sy...
July 22, 2014

3D Machine Vision - the key to automation

When it comes to the automation industry, machine vision continues to grow increasingly important. Without machine vision, automation is not possible. This webcast, sponsored by MVTec and presented...
July 17, 2014

Archives

Click here to view archived Vision Systems Design articles