The power of wideband hyperspectral imaging

With better light, more insight!

Quality is crucial across many industries, whether it's electronics, food, or any other product. Ensuring quality requires effective testing, and we all know that with more and better light we can “see” better. This also applies to quality control and inspection. As technology evolves, the structures to inspect are becoming smaller and smaller, and finding inconsistencies on a smaller scale improves product reliability and lifetime. Different materials also appear differently under different light sources, and the need for better and more light increases further.

Initially, we performed inspections with stronger lamps (halogen). However, halogen uses more energy, with the risk that objects to be inspected are getting too hot.

Then, lasers arrived. With lasers, we could see better and with more detail, and because lasers could focus their light beam, we could also look more precisely, exactly at the point of interest. But sending a continuous laser beam at something, on a very small spot, made it hot again.

Next came the pulsed lasers, turning on and off at frequent intervals and so quickly that it could not be noticed so they looked like “on” all the time. Unfortunately, even when lasers are pulsed, they still have an inherent disadvantage as they are, for all intents and purposes, monochrome.

This means that we can only inspect in one color, a serious step back from where we came from with full-color inspection. Fortunately, tunable lasers have been invented that can “wiggle” the frequency of the laser, so we get some sense of color. Of course, we can work with multiple monochrome lasers next to each other, and mix the monochrome lights, but in a way, this is still not true multi-color – it is more “multiple mono-color”, for each color tuned into specifically and sequentially. So, going back to quality inspection: tunable lasers are a hassle, but we accepted its limitations because this was the best we could get with tunable lasers.

Hyperspectral imaging on steroids

Fortunately, today, nature is helping us. At SuperLight Photonics, we have invented the technology to make full-color pulsed wideband lasers. This laser has a wide spectrum in the NIR (near infrared, at wavelengths from below 1000 nm to over 2000 nm) and can replace traditional scanning lasers with superior quality.

The many advantages are obvious:

1. Higher quality images, because no integration of monochrome pictures is needed and

2. No need to stabilize the object, actually the reverse: an assembly line can run faster because the recording time can now be reduced drastically

3. Immediate action can be taken, no intermediate processing time is lost to do interventions

4. A continuous wide spectrum provides more information about a surface, which can manifest itself through various ways such as seeing texture more clearly, identifying boundaries of different materials, characterizing shape in three dimensions, as well as determining contrasts, hues, and how the material is stacked in depth. This can be compared to watching black and white TV versus color TV.

In fact, the spectrum of a modern wideband laser is so wide, that we can even peer into the molecular composition of the material, opening many more quality inspection opportunities.

On top of this, the provided spectrum of wideband lasers is fully coherent (spatial and temporal), resulting in less scattering and very low noise, providing high sensitivity at faster processing times of the surfaces and objects to be scanned and inspected.

So, all-in-all, the expectation is that Wideband Hyperspectral Imaging will revolutionize the field of spectral imaging as it not only provides operational advantages (faster, less processing time), it also produces better quality imaging.

In short: with better light, more insight!