Further strengthening of the lens can be attained by using a liner inside the lens bore to concentrate the magnetism to an even smaller area. Condenser lenses gather the electrons of the first crossover image and focus them onto the specimen to illuminate only the area being examined. Condenser aperture is used to reduce spherical aberration. Specimen stage is where the sample sits for insertion into the electron beam. It can be caused by poor contact between the grid and the specimen holder causing a buildup of heat and static charges.
Objective lens is used primarily to focus and initially magnify the image.
Cold finger is an anticontaminator. This must be filled with liquid nitrogen before the microscope is used. Objective aperture is used to enhance contrast. Holey grid is a TEM grid support coated with a thin plastic film and a stabilizing carbon layer. Fresnel fringes result when diffraction occurs with the electromagnetic radiations and an unclear image of the irradiated object is formed.