Why use infrared imaging?
IR has a longer wavelength than visible light so can transmit further into certain materials such as glass, semiconductor, paper, cloth and plastic. As a result, certain defects or flaws can be detected with IR which cannot be seen with visible light.
Machine Vision System Considerations
When building an IR vision system, the correct combination of camera, lighting and software components must be considered. For cameras, the speed of measurement, level of sensitivity and price are important factors when deciding on the optimum system configuration. The choice of lighting directly affects the choice of camera since different camera sensors have different optimum wavelength sensitivities.
Infrared Machine Vision Lighting Considerations
Designing any machine vision system is as much about managing trade-offs as it is about optimizing the systems performance at an acceptable cost.
The material under inspection determines the range of wavelengths that can be utilized as different materials absorb different wavelengths more easily. It is important to choose your wavelength correctly as even wavelengths a few nanometers apart can have wide variations in price and optical efficiency.