Calibration of photoluminescence experiment

Photoluminescence in a semiconductor at room temperature is quite difficult to distinguish from the many nonlasing optical lines from the laser, therefore, a blank test is very important. In so doing, the noises of the detector has to be taken into account. The calibration, however, mainly depends on the detector and is less dependent on other components. Instead of using black-body radiation light source and pyroelectric detector, we use globar lamp and PbS detector; because of the difficulty in the former case in doing alignment of optical path (invisible) and operating at a lower signal level from the detector. The employment of a computer allows real time data acquisition, data averaging and real time displaying, plus, we can take the advantage if the scanning should terminate as the result is unexpected; better yet, store data and spectra for future need. The comparison between calibrated and uncalibrated spectrum shown that there are in fact significant deviations