“The most delicate parts of a QCL are the laser chip itself and the bonds connecting it to the ceramic pads. Therefore the QCL should be touched only at the copper carrier (far from the laser chip and the bonds), or at the ceramic pads (again away from the bonds).”
“A CW QCL is tested only with continuous excitation, where any pulse longer than one millisecond is seen as “continuous”. The performances shown on the datasheet are the performance in the steady state and do not consider transient effects that occur in this first millisecond.”
“The window thickness is 2.0 +/- 0.1 mm. The laser facet is 4.5 +/- 0.5 mm from the exterior facet of the window and 2.5 mm +/- 0.5 mm from the inside facet. The window is 1.0 +/- 0.2 mm recessed from the front of the LLH.”