A brief history of laser non-destructive tire testing

HOLOGRAPHY

First made practical in the 1960’s, developed in the labs at the University of Michigan and used for non-destructive testing of tires starting in the early 1970’s. Extremely sensitive to vibration.

HOLOGRAM

An image produced from a 70 mm film negative, reconstructed in a viewer. Difficult and costly to produce.

SHEAROGRAPHY

Invented at Oakland University in the late 1970’s and developed into a practical film based tire testing machine in 1980. Digital Shearography became practical in the 1990’s and has been used for tire testing since.

SHEAROGRAM

An image originally produced from a 35 mm film negative and reconstructed in a viewer. Later produced and displayed digitally. An excellent tool, but test results are difficult to interpret by a technician or a computer program.

DIFFEROMETRY

Invented and developed at L-RAY in 2003, specifically for high-speed production tire testing.  Suitable for non-destructive testing of many other products and substrates.

DIFFEROGRAM ä

An image produced digitally with results that are easy to interpret by a technician or a computer program. The anomalies are shown in a contrasting color and are a direct representation for size and shape, unlike Shearography in which the anomalies are shown as a double image.