Abstract: A sensor in the probe head of a coordinate measuring device supplies probe signals. The first, and if necessary, higher time derivatives of the probe signals are formed and evaluated for the exact determination of the moment of contact of the probe head with a workpiece to be measured. During the evaluation, the time course of the differentiated signals is examined by means of automatically generated trigger thresholds.

Abstract: A knife holder for a microtome has actuating levers for fastening or for releasing the knife on the knife holder, constructed such that in the position effecting the fastening of the knife, the actuating levers extend at least partially over the cutting edge of the knife. The actuating levers thereby act simultaneously as finger protectors and prevent inadvertent contact with the cutting edge in the side regions of the knife when the knife is fastened. The fastening of the knife takes place by means of permanent magnets, which are arranged in the base portion of the knife holder and motion-coupled to the actuating levers which cover the knife edge.

Abstract: The invention is directed to a zoom device which is built up of several lenses wherein at least one parallel entry beam is changed with respect to its diameter. The exit beam has the same optical axis as the entry beam. The zoom device of the invention is assembled from several zoom systems. The optical axes of the lenses of the different zoom systems are arranged so as to be mutually parallel or at least in a fixed spatial relationship so that in a beam made up of many individual beams the defined diameter remains constant because of the axes of the outer individual beams.

Abstract: The invention is directed to a coordinate measuring apparatus wherein the drives (3, 5, 6) for the measuring sleds of the apparatus are controlled on circularly-shaped paths to machine-control adjust the spatial orientation of the probe pin 9. The probe pin is attached to a passive rotation-pivot joint and has a probe ball which is driven into one of several centering gaps of a body 10. In this way, a separate drive for the rotation-pivot joint 8 is not needed.

Abstract: A viewing arrangement includes an objective (5) having a variable intersection distance and an intersection-distance dependent oblique illumination (7) which is separate from the objective (5). The oblique illumination (7) includes two illuminating beam paths (9, 11) for completely illuminating contoured objects without shadows. The illuminating beam paths (9, 11) are inclined toward each other ahead of the object (13, 16) to be viewed. The mutual inclination of the two illuminating beam paths (9, 11) is dependent upon the particular intersection distance of the objective (5).

Abstract: A drive system for the conversion of a rotary motion into a linear motion contains a belt drive similar to a block and pulley system, and a system of a rack and pinion that is driven synchronously with the belt drive. The pinion and the rack are adjusted with respect to each other such that the teeth of the pinion engage with relatively large play in the rack. When driving under normal load, the drive takes place without loading of the rack and pinion system by the belt drive, so that the reversal backlash and the play of the rack and pinion system remain without effect on the displacement motion. When an overloading of the moving part and a corresponding stretching of the drive belt occur, the tooth flanks of the pinion and of the rack are supported against each other and in this manner prevent tearing or overloading of the drive belt.

Abstract: A pancratic magnification system for at least two observation beam paths within a stereo microscope consists of a first and a second optical component that are displaceable in a defined manner along a common optical axis, following which a third, stationary, optical component is arranged. Variation of magnification is achieved by means of defined displacement of the first two optical components. A focusing on a desired object plane can be effected by displacement of only the first optical component. The pancratic magnification system is arranged after a common main objective for said at least two observation beam paths within the stereo microscope.

Abstract: The invention relates to a stereoendoscope having a sight line folded relative to the tube axis. The endoscope includes a distal front optic having a deflecting prism 4b. The deflecting prism 4b is mounted between a component 4a having a negative refractive power and a proximal component 4c having a positive refractive power. The inlet pupils 11 of the viewing component are imaged demagnified in the reflecting prism 4b by field optics (7, 7', 13) and transmitting optics (8, 8', 14). In this way, the beam can be guided free of vignetting without field cropping for both stereo channels through the endoscope tube and through the reflecting prism 4b even for a large object field angles and without image cropping. The endoscope tube 2 and the viewing component 1 are rotatable with respect to each other about the optical axis 12 within the endoscope tube 2 so that the line of sight can be changed for a viewing component fixed in space. The stereo basis remains for a rotation of the endoscope tube 2 fixed in space.

Abstract: A gas laser is excited by means of a high voltage discharge, at least one firing pulse being applied to a gas discharge tube. The firing pulse can be initiated by a release signal which is applied to an electronic firing unit. Firing pulses then applied to the gas discharge tube until a check-back signal concerning the successful firing of the gas discharge tube is supplied to the electronic firing unit by a detector unit which monitors the operating state of the gas discharge tube.

Abstract: The invention is directed to an immersion oil for microscopy. The immersion oil includes an ester or ether with tricyclodecane structure as a main constituent and one or more high-boiling liquids as minor constituents. The immersion oil is free of halogens and exhibits a high UV-transmissibility and is characterized by low intrinsic fluorescence because the components utilized can be vacuum distilled.

Abstract: The invention is directed to a method for controlling the emission current of an electron source and to a correspondingly controlled electron source. For this purpose, a parallel circuit comprising resistors 6 and field-effect transistors 7 is connected in the high-voltage circuit between the cathode 1 and the control electrode 2. The supply voltage for the field-effect transistors 7 is generated by voltage dividing the voltage across the resistors 6. The measurement of the emission current takes place at low-voltage potential and a control signal obtained from the measuring signal is optically transmitted via a light-conducting fiber or a light waveguide to the control circuit in the high-voltage part. The emission current control at high-voltage potential is provided without additional voltage supplies. Additional insulating transformers are therefore not required.

Abstract: The invention is directed to a probe head of a coordinate measuring apparatus for conducting measurements on a workpiece. The probe head has a first longitudinal axis and has a probe pin mounted on the probe head. The probe pin has a second longitudinal axis defining an angle with the first longitudinal axis. A joint-free, rigidly-configured adjusting device adjusts this angle when the probe pin is not in contact with the workpiece.

Abstract: The invention relates to a process for providing a bearing of a tilting device, which makes possible a tilt around at least one axis, with a tilting member, a base member, and a bearing situated between these two members. The center of gravity of the tilting member is situated at the pivot point of the bearing. A first portion of the tilting member is arranged above the pivot point, a second portion of the tilting member is arranged below the pivot point, and the weight of the first portion of the tilting member and the weight of the second portion of the tilting member correspond to each other.

Abstract: In a procedure for correlating different coordinate systems in computer-supported, stereotactic surgery, without the use of additional referencing markers, partial topographical information is collected by means of a surgical microscope mounted on a carrier system, and this partial topographical information is spatially correlated with the diagnostic data generated prior to surgery using a suitable correlation algorithm.

Abstract: At least one narrow-band emitting pump radiation source is provided in a laser arrangement having a laser medium to be pumped. The supplied pump radiation includes at least two pump radiation components which are different with respect to power. The component with lower power functions to generate a visible target beam. Such a laser arrangement is especially suitable in a medical laser system.

Abstract: A stereotactic adapter on which a surgical therapeutic and/or diagnostic instrument is reproducibly mounted and attached to a surgical microscope that can be positioned in several spatial degrees of freedom. A position recognition system integrated in the surgical microscope permits safe positioning of the instrument used, given the geometric arrangement and the geometric dimensions of the surgical microscope, the adapter, and the instrument.

Abstract: An image stabilizing device for optical equipment has at least one force exerting drive element for the compensation of vibrations acting on an optical arrangement in the optical equipment from its surroundings in at least one direction perpendicular to the optical axis. The force exerting drive elements is a linear motor. The image stabilizing device is installed in or on the optical equipment.

Abstract: The solid-state oscillator, preferably a watch crystal (1/2), is mounted with its direction (S) of vibration at an angle to all three measuring directions (x, y, z) of the coordinate measuring apparatus. The oscillator circuit of the solid-state oscillator is connected to an electronic circuit which generates two different contact signals. Both measures make it possible to reduce the dependency of the contact uncertainty of the measuring direction.

Abstract: A multifocal spectacle lens has two optically effective surfaces with powers in the far reference point from -4.0 dpt to +4.0 dpt in the stronger principal section. The spectacle lens has cylinders from 0.0 dpt to 4.0 dpt and an addition of 1.00 dpt to 3.00 dpt. The multifocal area is at least aspherical and can be differentiated continuously at least twice and is not axial symmetrical. The multifocal surface includes a far vision zone, a near vision zone and a progression zone lying between the near and far vision zones. The lens body is configured to incorporate a plurality of features within an elliptical region on the surface of the lens body extending 50 mm measured horizontally and 40 mm measured vertically from the measurement point. These features are all satisfied together within the elliptical region. One of the features is that the near-reference point is at most 21 mm perpendicularly below the far-reference point and displaced by about 2.5 mm toward the edge.

Abstract: A stage for microscopes has a transparent ceramic glass plate on the working region on its object side and a brightly colored, light-scattering layer between the ceramic glass plate and the metallic base portion of the stage. Light is coupled into end faces of the ceramic glass plate by means of lamps or a glass fiber arranged in the base portion. The stage has outstanding resistance to wear and scratches due to the ceramic glass. By the additional illumination of the ceramic glass, the specimen regions lying outside the illuminating field of the condenser are weakly illuminated against a bright background, so that the observer can select visually, without magnification, object regions of interest and then push them into the illuminating field of the condenser. The ceramic glass covers the condenser opening in the base portion of the stage, so that the condenser is protected against falling contamination.