Why spectroscopy is only as good as the light behind it

Spectroscopy sits at the heart of material analysis, industrial automation, and scientific discovery. But no matter how advanced the instrument is, the results are always limited by the quality of the light feeding the system.

Choosing wisely is essential because spectroscopy is only as good as the light behind it.

In this article, we compare the most commonly used wideband light sources and explore how on-chip supercontinuum technology is reshaping the landscape.

A changing landscape... Not all wideband light sources are equal

In the past, spectroscopists had to choose between halogen/plasma lamps, LEDs/SLEDs, and legacy supercontinuum lasers. Each brings trade-offs in brightness, spectral range, stability, integration complexity, safety, and cost.

• Halogen and plasma lamps offer wide spectra but lack brightness

• LEDs and SLEDs are compact and scalable, but constrained to narrow ranges

• Legacy supercontinuum lasers provide broad spectra but introduce instability, size, cost, and class-4 safety barriers

  
  

This creates a frustrating dilemma: performance versus practicality.

Side-by-side How different light sources compare

Spectroscopy done right: what really matters

1. Brightness when every photon counts

Brightness often becomes the bottleneck, especially when coupling into fiber or operating at larger standoff distances. Halogen, plasma, and LEDs lose the majority of their photons because so few are directed toward the detector, extending integration times and slowing throughput. SLEDs and supercontinuum lasers deliver orders-of-magnitude higher radiance, enabling faster and cleaner measurements.

2. Spectral range without complexity

LEDs and SLEDs typically cover only tens of nanometers. Achieving a broader range requires co-packaging multiple emitters, increasing cost and complexity. This approach fails for applications requiring time-coherent pulsed light. A true supercontinuum source provides a full wideband output in a single device.

3. Spectral stability that keeps up with time-critical applications

Legacy supercontinuum lasers demand averaging over tens or hundreds of thousands of pulses to achieve stable spectra and pulse-to-pulse variation makes real-time, high-speed spectroscopy extremely challenging.

4. Scalability for real-world deployment

LEDs and SLEDs are inherently scalable technologies. Legacy supercontinuum lasers are not: they are large, component-heavy, alignment-sensitive, and require class-4 laser safety precautions. An integrated photonics architecture changes this equation by being foundry-produced and ready for further feature integration.

A new path forward: On-Chip Supercontinuum

Spectroscopy no longer requires a trade-off between performance and practicality.

With an on-chip supercontinuum source, you get wideband output, high brightness, stability, compactness, and scalability, all in one architecture. This opens the door to new classes of systems in industrial sensing, hyperspectral imaging, OCT, semiconductor inspection, and beyond.

Let’s talk about what this can unlock for your applications

If your spectroscopy system could benefit from higher brightness, broader spectra, better stability, or a more scalable architecture, we would love to connect.