摘要:
A method of operating a particle-beam apparatus such as an electron microscope and the like equipped with a deflection system arranged at the beam path and a control device operatively connected to the deflection system includes adjusting the excitation of the deflection system by means of the control device to direct the particle-beam for a selectable time period onto a location of the object whereat the object is to be investigated and, again adjusting the excitation of the deflection system by means of the control device to direct the particle-beam in the remaining time to another location of the object whereat the particle-beam passes through the object, the last-mentioned location being disposed laterally of the first-mentioned location.
摘要:
A scanning, corpuscular-beam microscope which includes a beam deflection system comprising a first stage for deflecting the beam out of the optical axis of the microscope and a second stage, disposed after the first stage along the beam path, for deflecting the beam towards the optical axis of the microscope. A first objective lens having a short focal length is disposed after the second beam deflection stage along the beam path for focusing the beam on a specimen. The improvement of the invention comprises the provision of a second objective lens having a long focal length which is disposed above the first objective lens along the beam path. The second objective lens is excited for low magnification of the specimen by the microscope and redirects the deflected beam in a direction approximately parallel to the microscope axis and focuses the beam on the specimen. The first objective lens and the second stage of the deflection system are inoperative during the redirection of the beam by the second objective lens.
摘要:
An improved method for pictorially displaying a diffraction image in a transmission-type, scanning, corpuscular-beam microscope in which a beam detector is scanned by a diffraction image moved by a deflection system in line-raster fashion in a first, predetermined direction over the beam detector. The beam detector generates an output signal for controlling the brightness of a television monitor which displays the diffraction image. The improvement of the invention comprises the step of additionally exciting the deflection system so as to move the diffraction image in another, second direction over the beam detector which is perpendicular to the first, predetermined direction so that a predetermined area of the diffraction image which includes at least part of the cross-section of the maximum intensity of the null reflex of the beam is excluded during scanning of the beam detector and the diffraction image displayed by the television monitor is blanked in an area corresponding to the cross-section of the diffraction image which is excluded during scanning.
摘要:
A scanning transmission-type electron microscope including an annular-shaped detector disposed concentrically with respect to the optical axis of the microscope behind a specimen along the microscope beam path, and means for amplifying output signals generated by the detector. The detector comprises a scintillation detector and the microscope includes a photoelectron multiplier coupled to the detector and disposed outside the microscope beam. A curved light guide is also coupled to the detector and the photoelectron multiplier and includes a canal which extends through the light guide along the microscope axis for permitting the passage of a central ray cone of the electron beam of the microscope through the light guide.
摘要:
A method and apparatus for focusing the objective lens of a scanning transmission-type corpuscular-beam microscope. In the method, the beam of the microscope is deflected by a deflection system excited in sawtooth fashion and generates a raster consisting of parallel lines on the specimen to be examined. The microscope includes a beam radiation detector disposed behind the specimen along the beam path which generates an output signal which controls the brightness of a picture tube monitor operated synchronously with the raster. The improvement of the invention comprises the steps of measuring, during the exposure of a specimen point, partial beam radiation intensities in the cone of the beam at two points disposed symmetrical with respect to the longitudinal axis of the beam cone by means of the detector, the effective input area of the detector being smaller than the cross-sectional area of the cone of the beam at the same height in the microscope. The lens current of the objective lens is then adjusted so that the output signals generated by the detector are equal for the beam radiation measurements at the two points. An apparatus for automatically focusing the objective lens in the foregoing manner is also disclosed.
摘要:
A method for pictorially displaying output information generated in the form of an electrical signal by an apparatus for imaging an object which includes a first display means for visually displaying a working image of the object and a second display means for visually displaying an orientation image of the object. The orientation image is obtained by varying the operating parameters of the apparatus and is displayed simultaneously with the working image. The improvement of the invention comprises the steps of generating the orientation image once, storing the orientation image in an image storage means, and then reproducing the orientation image from the generated image stored in the image storage means.
摘要:
An improved transmission-type, scanning charged-particle beam microscope including a television camera tube and a television display tube for generating and displaying a diffraction image of a specimen to be examined. The improvement of the invention comprises the provision of a transparent fluorescent screen disposed in the ray cone of the beam behind the specimen along the beam path in the microscope, light-optical means adapted for imaging the fluorescent screen on a target of the television camera tube, and detector means for integrally detecting radiation emanating from the fluorescent screen.
摘要:
A device for setting an electric command variable comprising parallel circuit branches for the coarse and fine adjustment of the variable is disclosed. In particular, the fine and coarse adjustment branches each include a digital bi-directional counter and a digital-analog converter. Upon exceeding the limits of the conversion range of the digital-to-analog converter of the fine branch, the counter therein is adjusted to a value which corresponds to a middle setting of its associated converter. To prevent the latter adjustment from causing a variation of the analog command variable, a corresponding correction of the counter in the coarse branch is then made. The present device has particular application in the setting of the energizing currents in magnetic lenses of an electron microscope.
摘要:
A resilient shaft coupling includes a annular member constructed of a hexagonal resilient joint disc and at least one attaching element which includes a plurality of flange arms. The resilient joint disc includes attaching regions at its corners provided with axial connecting element bores. The straight sides of the joint disc are provided with thin web regions which permit elastic deformation.
摘要:
A resonant circuit which includes the input capacitance of the clock pulse inputs of a shift register (10) is pulsed by a sinusoidal wave at voltage peaks of the wave by an oscillator delivering barely enough energy to overcome the damping of the resonant circuit. The oscillator may be crystal controlled and, instead of having a single ended output for delivering energy only on peaks of one polarity, may be in push-pull form reinforcing oscillation peaks of both polarities. This circuit is easily combined with arrangements for switching oscillator frequency from one value to another and/or arrangements for interrupting the clock pulse output for timed intervals after each loading or unloading of the shift register. The loss power dissipation is reduced to about 6% of the loss power dissipation of a square pulse drive for the clocking of the same shift register. The low loss drive for shift register advancement is applicable to a variety of analog stepped storage and delay devices, such as charge coupled devices and "bucket brigade" devices.