Exposing with electrons will damage many materials. In order to protect the specimen while the camera is not in use, most TEMs provide a beam blanker that deflects the beam in the electron gun by using the gun tilt coils. However taking an image directly after deactivating the beam blanker, often blurs the image due to the changing charging conditions.
 
The new Shutterbox II allows pre-exposing the specimen, i.e. the beam illuminates the specimen, but the exposure shutter is not opened. This pre-exposure allows stabilization in the case of charging. The Shutterbox II uses the two independent TEM shutters, beam blanker BB and exposure shutter SH.

To prevent damage to mechanical TEM shutters by too short opening times, a minimum shutter open time can also be defined (e.g. 500 ms).