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Optics & Infrared Sensing

Optics & Infrared Sensing

Quantum Cascade Lasers (QCL) Packaging

Quantum Cascade Lasers (QCL) are a key component in developing infrared chemical sensing applications because they can be engineered to provide appropriate emission wavelengths with stringent performance requirements. However, as these chemical sensors mature in the laboratory and transition to the field, they will require compact and robust QCL transmitters that would significantly simplify sensor designs without compromising performance. Currently, QCLs operating at room temperature require bulky thermoelectric cooling (TEC) and optomechanics to hold the collection optics to efficiently collect and collimate the laser emission. PNNL is currently miniaturizing the QCL transmitter design to fit into a commercially available High Heat Load (HHL) package incorporating a TEC and custom designed collection and collimation optics.

Figure 1 Schematic of a packaged QCL laser incorporating off-the-shelf and custom components
Figure 1 Schematic of a packaged QCL laser incorporating off-the-shelf and custom components

The QCL transmitter package above is a first generation product. Its design is flexible to allow for a variety of configuration including: 1) windowed package for general laboratory use; 2) multimode fiber-coupled for power delivery applications; 3) external singlemode collimator configuration for applications requiring high quality Gaussian beam; and 4) external cavity tunable laser configuration for applications requiring precise- or multi-wavelength operation.

Optics & Infrared Sensing

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