Discussion Category: NIR Spectrophotometers
Erratic transmission - PE PERKIN ELMER LAMBDA 9 UV/VIS/NIR SPECTROPHOTOMETER
I have a Lambda 9 UV/VIS/NIR spectrophotometer ( Lambda 9 Is an option in the pull-down.) which show erratic transmission in certain ranges (>2400nm, 600-900nm, <250 nm). I installed the lamps from my Lambda 2 to rule out them out. I recently aligned the beams as best I could but I don't have the jigs to do it 100% correct. I assume that since some of the UV/VIS range is good and some of the NIR range is good, both detectors are still good. I would appreciate any help you can provide to solve this problem. At the moment, I assume it is is some of the filters in the color filter wheel. I would also appreciate advice on how to clean these without making the problem worse. Much appreciated, Doug
Reply byI found one of the mirrors going to a diffraction grating was loose and wobbling. After realigning everything, I only have erratic readings <350nm, and at the tail ends of the NIR sensor 800-1100, > 2500nm. At this point, I suspect all but the >2500nm will resolve with finer alignment. I also suspect my UV lamp is not aligned.