Two-Color Detectors

Robust Dual-Wavelength Detection

Two-color, or “sandwich,” detectors are designed for applications that require extended spectral coverage or remote temperature measurement. These devices feature one photodiode stacked on top of another, using either the same or different semiconductor materials.

The stacked architecture works because different semiconductor materials absorb light at different wavelengths. The front element captures shorter wavelengths while transmitting longer ones through to the rear element. This allows a single compact device to simultaneously sense across two distinct spectral bands, something that would otherwise require separate detectors, additional optics, and more complex system integration. A wide range of standard and custom configurations is available, including combinations of silicon, germanium, InGaAs, and extended-wavelength InGaAs.

Download our datasheet and our white paper, An Introduction to InGaAs Over InGaAs Ratio Pyrometry, to learn more.