Abstract: A description is given of an illuminating device for a microscope (1), having a light source (2), an illuminating optical system (3) and an LCD (5) arranged in the illuminating beam path (4). The illuminating light is directed onto the object (6) from the light source (2) via the LCD (5), a transparent/opaque pattern being generated on the LCD (5) by means of a control and calculating device (7). The LCD (5) is arranged in a plane (AP′) which is conjugate with respect to the field diaphragm plane or aperture diaphragm plane (AP) and has a planar matrix composed of individual pixels arranged next to one another and of the same dimensions, the pixels each being constructed such that they can be driven individually to generate an arbitrary transparent/opaque pattern. The control and calculating device (7) is constructed as a computer with a graphics card.

Abstract: A microscope objective having a plurality of lens assembly holders, one of which is designed as a correction holder (F4) for matching to different cover slip thicknesses and can be moved axially along the optical axis of the objective for position changing between lens assembly holders which are stationary relative to the objective. A cam ring (6) is arranged within the holder support (1) such that it can rotate. The correction holder (F4) is supported by means of a ball (11) or a bolt (24) on its cam (7). A pin (14), which can move radially in a holder support, is firmly connected at its one end to the cam ring (6), and its other end extends into a knurled ring (16). Turning the cam ring (6) by means of the knurled ring (16) changes the support point between the correction holder (F4) and the cam (7) of the cam ring (6), resulting in the correction holder (F4) being moved exclusively in the axial direction.

Abstract: An exchangeable condenser system for a phase-contrast illuminating system (12) for microscopes has a plurality of different light rings (5), arranged on a nosepiece plate (4), assigned to the condenser optical system (6). The condenser optical system (6) can be exchanged independently of the light rings (5), the focal lengths F.sub.n of the exchangeable condenser optical systems (6) being selected relative to one another in the ratio F.sub.n =F.sub.0 *X.sup.n and the average diameters D.sub.n of the light rings (5) being selected relative to one another in the ratio D.sub.n =D.sub.0 *X.sup.n, where X>0, n=0,1,2,3, . . . .

Abstract: A gear unit (1) for focusing microscopes and having coarse adjustment, fine adjustment and extra-fine adjustment is described, in which, for the purpose of focusing, the object stage (5) is moved via a toothed gear (6). Coaxially arranged control knobs (7, 8) are provided on the microscope as manual control elements. The control knobs (7, 8) are connected via a drive shaft (9) and the gear unit (1) to a toothed rack (10) of the object stage. The control knob (7) for fine adjustment is provided on a rotation shaft (11) arranged so as to be capable of longitudinal displacement. Arranged on this rotation shaft (11) are at least two gear wheels (12, 13) of different diameter for fine adjustment and extra-fine adjustment. One of the gear wheels (12, 13) is connected to the gear unit (1) via the longitudinal displacement of the rotation axis (11).

Abstract: An object holder (7) for thin slides (4) is described, in which the object holder (7) has a baseplate (8) as well as a lower lying supporting surface (9) as a receptacle for the slide (4). Arranged on the baseplate (8) is a spring steel (10) which has a knife edge (11). This knife edge (11) projects beyond the baseplate (8) onto the lower lying supporting surface (9), the slide (4) being fixed via a clamping mechanism between the knife edge (11) and the supporting surface (9).

Abstract: A regulated power supply unit with an electronic transformer having an input for a transformer power supply voltage on the primary side, an output for an operating a.c. voltage with a higher-frequency component on the secondary side, and a control device with a variable resistor by means of which the operating a.c. voltage may be set. There is an inductive or capacitive separator component by means of which the higher-frequency component of the operating a.c. voltage can be separated out and taken as the input voltage to a first and a second rectifier circuit. The output voltage of the first rectifier circuit is applied to an amplifier-comparator circuit as its supply voltage. A reference generator circuit is connected to the first rectifier circuit and to the amplifier-comparator circuit. A reference for the operating a.c. voltage can be set by the reference generator circuit.

Abstract: A contrasting process and device allows a relief contrast to be obtained for microscopic amplitude and/or phase objects. The input aperture (L') of the condenser (2) is partially and asymmetrically masked at the same time as an image (S') of a sector diaphragm (S) is generated in the output aperture (L") of the objective lens (3), a phase segment (8) of a phase plate (7) covering the image (S') at least partially. The size of the phase segment (8) may be adapted to the size of the image (S') cutout; it may however also be substantially smaller. In the latter case, the sector diaphragm (5) may have additional attenuating sectors (D) made of semi-transparent material with a defined attenuating factor, for example 15%. The process and device are suitable for transmitted light and/or reflected light microscopy in a normal or inverted beam path.

Abstract: A device for stabilizing the focus in a microscope (1) is described which has an objective (2) and a specimen stage (3), constructed in a movable fashion, for the purpose of setting the focus. The specimen stage (3) is constructed such that it can be moved via a toothed rack (4) and a drive gear (5) along the optical axis (22) of the objective (2). When the microscope (1) is heated by integrated electronic components (6) and/or an illuminating device (7), the body (13) of the microscope expands, and the microscope (1) is thereby defocused. Two rods (8 and 9) connected to one another, which have a different thermal expansion, are arranged between the toothed rack (4) and the specimen stage (3) for the purpose of compensating for the defocusing.

Abstract: A change-over device has a plurality of centerable reception rings (10), inserted into a sliding bearing (9), for optical components. A spring element having a plurality of tongues (16) split in the longitudinal direction is provided in such a way that in each case successive halves of adjacent tongues (16) rest against the rim of a reception ring (10) under spring pressure.

Abstract: A microscope (1) is described which has an adjustment knob (2) arranged on the microscope (1) and an encoder (6) assigned to the adjustment knob (2). The encoder (6) is connected to a control device (3). The control device (3) is assigned positioning motors (4, 14, 18, 23, 24) for motorized setting of different microscope functions. The preselected function which can be controlled by motor is preselected via switches (7, 11, 15, 19, 21) arranged on the microscope (1) and triggered via the control device (3) as a function of the encoder pulses generated by the adjustment knob (2). The motor drives are assigned sensors (8) which detect the operating position of the activated microscope function. When the maximum operating position is reached, a braking motor (9) connected to the adjustment knob (2) is activated via the control device (3) and renders the rotation of the adjustment knob (2) more difficult up to complete blockage.

Abstract: The invention provides a switchable bright-field transmitted-light illumination device for microscopes which provides for in each case two objectives of different apertures in both switch positions a simple automatic illumination arrangement without adjustment of the position and of the opening of the diaphragms. For this purpose, in an illumination device, comprising light source 1, collector 2, field diaphragm 3, aperture diaphragm 4 and basic condenser 7 with removable condenser head 8 or condenser lens element 11, which can be switched in alternatively to the condenser head 8 between the aperture diaphragm 4 and the basic condenser 7, the aperture diaphragm 4 is arranged between the collector 2 and the field diaphragm 3 and is imaged by an intermediate imaging by at least two auxiliary lenses 5 and 6 into a plane 12 conjugate with the aperture diaphragm 4.

Abstract: An interference filter having 17 coatings of alternating high and low index materials is located on the illumination path of an optical device and provides correction for green color distortion on the observation path and correction for blue color distortion on the photo path in order that both the observed image and photographed image are color neutral.

Abstract: A process and a circuit arrangement are proposed for electronically monitoring the overload on electric motor drives and in the case of which process and circuit arrangement speed is .monitored in addition to the known methods for real power monitoring. This also enables monitoring of the operating state of an electric motor drive, which is subject to a load, below the nominal rotation speed. This allows monitoring of the overload not only in the case of electric motor drives in the direct-current mode but also in the pulsed mode, as well as in the case of stepping motors.

Abstract: A modular microscope system includes a plurality of stackable housing modules each having a plurality of inwardly pointing protuberances provided with one or more precision stop surfaces thereon for removably mounting and positioning a plurality of prealigned functional element carriers having corresponding precision stop surfaces thereon for engagement with the precision stop surfaces of the housing module protuberances.

Abstract: The microscope stand foot serves to accommodate an illumination device having optical components and having an aperture diaphragm and field diaphragm. The latter are assembled in a cylindrical tube held by a carrier, the tube being able to be fastened in the stand foot as a prefabricated unit. In this way, the assembly of the illumination device is simplified. When fastening the carrier in the stand foot, the tube rests under tension on mating surfaces, as a result of which an adjustment of the tube and thus of the optical components is dispensed with.

Abstract: A bright-field transmitted-light lighting device for a microscope is described, for the homogeneous illumination of the lighting field diaphragm (LF) at large fields and small apertures and for the uniform illumination of the aperture diaphragm (AP) at small fields and large apertures, A raster plate (3) is disposed in the lighting beam path (7). The raster plate (3) is designed as a plane-parallel, transparent plate which exhibits a circular rastering at the center.

Abstract: A microscope objective adjustable for different cover slip thicknesses includes an outer ring rotatable about an optical axis of the objective, an intermediate mount carrier having a plurality of inner lens mounts fixed thereto, and an inner correcting lens mount axially movable between a pair of fixed lens mounts. The correcting mount is coupled to the outer ring for rotation therewith by a follower pin extending through a curved cam slot in the intermediate mount carrier and into an axial groove in the outer ring, such that when the outer ring is rotated the correcting mount moves axially due to engagement of the follower pin with the cam slot and simultaneously rotates about the optical axis due to engagement of the follower pin with the axial groove.

Abstract: Methods are described for the control of the brightness in a manner independent of color and for the control of the color temperature in a manner independent of brightness, of the illumination light for a microscope device. An apparatus for carrying out the methods includes, beside a main light source 4, a secondary light source 5 with a color filter 6. Both light sources are electrically connected to a common regulating apparatus 8. By means of stored current values and by means of controllers 9, 10 and/or 19 which are to be operated manually, the light sources 4, 5 are driven using appropriate current values.