Page 613 - (DK) The Ultimate Visual Dictionary 2nd Ed.
P. 613

Hig H -performance microscopes
                       HOW A TEM WORKS            HITACHI S-3500H                Evacuated column
                                                  SCANNING ELECTRON
                                          Electron   MICROSCOPE                                  Screen
                Electron gun
                                          stream                                   Image
                                                                                   controls

                Aperture                  Aperture
                plate                     creates
                                          electron
                                          beam

                                          Condenser
                                          focuses          Vacuum
                                          electron         pump
                Specimen                  beam             cabinet
                stage
                                          Specimen



                                          Objective lens           HOW A SEM WORKS             Keyboard
                                          refocuses
                                          image formed
                                          by electron          Electron            Electron gun
                                          beam                 stream
                                                                                      Aperture creates
                                                              Aperture                electron beam
               Specimen                                       plate
               airlock                    Projector lens
                                          enlarges and                                 Condenser lens focuses
                                          projects the     Scanning coils              primary electron beam
                                          image            direct electron
                                                           beam across the                     Screen
               Phosphor                                    specimen
               imaging
               screen glows                   Binocular
               when hit by                    eyepieces
               electrons to
               create the
               image


                                                             Objective lens
               Cooling                                       refocuses
               device
                                                             electron beam
                                                                                                  Electron
                                                                                                  detector
                                                                                                  assembly
                                                               Specimen
              Camera                               Screen      stage                   Secondary
                                                                                       electrons from the
                                                                                       specimen surface
                                                         Specimen surface hit
                                                        by primary electrons

                                                                   Underside of
                                                                   caterpillar
                                                                   body



                                                                      Caterpillar
                                                                      foot
                                                         Keyboard
              Image controls
                                 Mouse                                           SEM IMAGE OF A CATERPILLAR
                                                                                                        611




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