Abstract:
A spherical grid for use in instrumentation comprising a rigid non-magnetic frame having a pattern of holes. Into each hole a flat wafer is placed, each wafer having etched therein holes defining the grid mesh. The frame maintains the geometric conformal shape allowing large units to be constructed.
Abstract:
In an electron microscope, having intermediate lenses between the object and the projection lenses, the first and second intermediate lenses are used for rotating the final electron microscope image without changes in magnification. The desired angle signal indicating to azimuth angle .theta. is designated by an operator. The absolute magnetomotive force .vertline.J1.vertline. and .vertline.J2.vertline. of the first and second intermediate lenses are controlled by a lens control means in the relation that (.vertline.J1.vertline.-.vertline.J2.vertline.) is proportional to the azimuth angle .theta. and (.vertline.J1.vertline.+.vertline.J2.vertline.) is nearly proportional to the square of the azimuth angle .theta..
Abstract:
An electron source section including a first detecting sub-section and a first control sub-section and an image formation section including a second detecting sub-section and a second control sub-section are arranged in series. The first detecting sub-section detects at least one of the shape, diameter, brightness and spatial position of a crossover image formed by the electron source section to become an electron source of the image formation section and the direction of emission of the electron beam emitted from such crossover image, thereby to control the first control sub-section. The second detecting sub-section detects at least one of the shape and size of an electron beam image formed on a subject to be irradiated by the beam, and the current of the electron beam forming the electron beam image, thereby to control the second control sub-section.
Abstract:
An electron beam from an electron gun is made to focus on a first position by a focussing lens system. The focussed beam is then magnified and projected on a screen through a magnification lens system having an objective lens, an intermediate lens and a projection lens.The excitation is so variable that the electron beam may be focussed also on a second position behind the projection lens.A specimen is positioned at the first position for normal electron microscope analysis, while, for a scanning electron microscope analysis, another specimen is put at the second position.
Abstract:
A scanning electron microscope comprising a double gap lens in its electron beam irradiating system. The double gap lens is arranged between the electron gun and the final stage condenser lens, and is excited by a lens current such that a large change of electron beam diameter may be controlled by a small change of lens excitation current.
Abstract:
A raster type particle-beam device has an electro-optical axis and defines a specimen locality on the axis. The device has a beam generator for issuing a particle beam along the axis toward the specimen locality, a condenser lens for focussing the beam onto the specimen locality, the lens being disposed ahead of the specimen locality and coaxial with the axis, a deflection system arranged about the axis intermediate the beam generator and the condenser lens, an imaging surface disposed beyond the specimen locality in coaxial relation to the axis for receiving the rays of the beam passing through the specimen, and a beam modifying structure for modifying the imaging properties of the beam, the beam modifying structure being disposed in the path of the beam intermediate the deflection system and the specimen locality.
Abstract:
An electron-beam illuminating system for an electrical apparatus such as an electron microscope or the like includes a cathode for supplying the electrons making up the electron-beam. A first anode is disposed beyond the cathode and defines therewith a beam axis extending in beam direction. A positive bias voltage on the first anode determines the emission of the cathode. An acceleration anode is disposed beyond the first anode and defines an acceleration path for the electrons emitted by the cathode. An acceleration voltage is applied across the cathode and the acceleration anode. A further electrode is located between the first anode and the accelerating electrode and defines conjointly with the first anode a space therebetween along the beam axis. A voltage is applied to the further electrode which is linearly proportional to the acceleration voltage. An auxiliary lens generates a first image of the source in this space. An electric circuit supplies a voltage to the further electrode which is linearly proportional to the acceleration voltage.
Abstract:
In an electron microscope comprising an electromagnetic objective lens and at least three separate electromagnetic projector lenses, the rotations produced by the lenses are mutually balanced out, so that the final image has a substantially constant orientation with changes in magnification. Preferably, magnification is set by a single control knob. Preferably, the microscope has two modes of operation, for different magnification ranges, the rotations being balanced out in both ranges.