Abstract: By using a surgical microscope device, it becomes possible to continue surgery more reliably, even in the case in which the picture of the operating site is no longer displayed normally. Provided is a surgical microscope device including: a microscope unit (110) that images an observation target, and outputs a picture signal; a support unit (120) that supports the microscope unit, and is configured as a balance arm; and an auxiliary observation device (30) that is attachable to the microscope unit or the support unit. A manually operated manual brake mechanism (40) is provided with respect to at least one of a plurality of rotation axis units constituting the support unit.

Abstract: New systems and methods are described for maintaining a desired steady state temperature differential between two objects that may otherwise undergo heat transfer to restore thermal steady state. In one application, a cooling microscope assembly and its use with conventional optical microscopes are described for achieving super-resolution imaging. The assembly allows for the high resolution imaging of samples at cryogenic temperatures while maintaining the temperature of the objective lens above freezing by employing circulation systems and a coupling fluid between the sample and objective lens.

Abstract: An observation optical system of a real-image type includes, in order from the object side, an objective system, a reverse-erecting system that erects an inverted image formed by the objective system, and an eyepiece system that allows a pupil to observe an erect image formed by the reverse-erecting system. The objective system includes, in order from the object side, a first lens having a negative power and a second lens having a positive power. The eyepiece system includes, in the order from the object side, a third lens having a positive power, a fourth lens having a negative power, a fifth lens having a positive power, and a sixth lens having a positive power.

Abstract: A laser beam machining device having a laser beam source and an equipment for deflecting a laser beam of the laser beam source for machining a workpiece is provided. The equipment includes a mounting body, a structural member having a reflecting surface, a flexible element by which the structural member is deflectable around an arbitrary space axis about an angle of deflection, a first forcing component and at least one second forcing component, whereby at least one of the forcing components are controllable such that the two forcing components are attracted towards each other or repel each other depending on the triggering. One of the forcing components is coupled to the structural member and the two forcing components are arranged and cooperate such that the structural member deflects around the arbitrary space axis about a predetermine angle of deflection.

Abstract: An observation optical system has an objective system and an eyepiece system in the order from the object side. The objective system includes, in the order from the object side, a first group having a positive power, a second group having a positive power, and a third group having a negative power. The objective system has an inverting optical system. The eyepiece system includes, in the order from the object side, a fourth group having a positive power and a fifth group having a positive power. The third group and the fourth group move in directions separating from each other along an optical axis to thereby perform variable power from a low magnification to a high magnification, and also the following conditional expression is satisfied: 0.28<H×L/f?0.55 ??(1).

Abstract: A surgical device includes a plurality of cameras integrated therein. The view of each of the plurality of cameras can be integrated together to provide a composite image. A surgical tool that includes an integrated camera may be used in conjunction with the surgical device. The image produced by the camera integrated with the surgical tool may be associated with the composite image generated by the plurality of cameras integrated in the surgical device. The position and orientation of the cameras and/or the surgical tool can be tracked, and the surgical tool can be rendered as transparent on the composite image. A surgical device may be powered by a hydraulic system, thereby reducing electromagnetic interference with tracking devices.

Abstract: A variable-magnification observation optical system includes an objective system, an erecting system, and an eyepiece system. The objective system includes a positive first group, a positive second group, and a negative third group in order from the object side. The eyepiece system includes a positive fourth group and a positive fifth group in order from the object side. The erecting system is located between the first group and the second group. The fifth group includes in order from the object side a negative meniscus lens and a positive lens with an air gap therebetween wherein the negative meniscus lens has a concave surface facing the object. The fifth group has at least one aspheric surface.

Abstract: An ophthalmic surgical microscope includes a beam coupler positioned along an optical path of the surgical microscope between a first eyepiece and magnifying/focusing optics, the beam coupler operable to direct the OCT imaging beam along a first portion of the optical path of the surgical microscope between the beam coupler and a patient's eye (an OCT image being generated based on a reflected portion of the OCT imaging beam). The surgical microscope additionally includes a real-time data projection unit operable to project the OCT image generated by the OCT system and a beam splitter positioned along the optical path of the surgical microscope between a second eyepiece and the magnifying/focusing optics. The beam splitter is operable to direct the projected OCT image along a second portion of the optical path of the surgical microscope between the beam splitter and the second eyepiece such that the projected OCT image is viewable through the second eyepiece.

Abstract: The invention relates to a tube for a surgical microscope. The tube has a base part, an intermediate part, which is pivotable about a rotational axis on the base part, and an ocular part which is pivotable about a rotational axis on the intermediate part. The imaging beam path is guided through the base part, the intermediate part and the pivotable ocular part. The tube has a tube lens system which transfers a parallel imaging beam paths into an intermediate image. The parallel imaging beam path enters via an opening in a connecting piece of the base part. The tube has a first displaceable mirror element which can be moved about the rotational axis on the base part. The tube lens system is a telesystem which has a lens unit having positive refractive power and a lens unit having negative refractive power.

Abstract: A stand for medical optical instrument capable of easily extending, adjusting easily a counter balancing according to a change of a weight of medical optical instrument such as microscope, as well as, maintaining stably a counter balancing regardless of a position of medical optical instrument.

Abstract: A microscope head includes a housing having a pivot axis located generally at a center of gravity of the housing. At least one handle is connected to the housing coaxially with the pivot axis. Mounting structure is for rotatably mounting a support arm coaxially with the pivot axis. A tension control ring is attached coaxially with the pivot axis for varying a rotation force required to rotate the housing with the handle about the pivot axis. A magnification selector mechanism is connected to the housing coaxially with the pivot axis.

Abstract: An observation apparatus includes a first member 9 supporting first optical elements L1L and L1R, a second member 7 supporting second optical elements L4L and L4R and the first member via balls so as to be movable in an optical axis direction, and a biasing device 11 generating a biasing force for clamping the balls. The first and second members include guide portions 7a, 7b, 9a, and 9b engaging with first balls so as to permit a rolling motion of the two first balls 10a and 10b in the optical axis direction and prevent the first member from displacing with respect to the second member in a direction orthogonal to the optical axis direction, and ball holding portions 7c, 7d, 9c, and 9d holding second balls 10c and 10d so as to permit a rolling motion of the second balls in the optical axis direction.

Abstract: An arrangement for equalizing binocular visual fields for microscopes and other optical instruments, with an eyepiece arranged in each beam path, and with diaphragms serving the purpose of visual field adjustment. The diaphragms are fixed or movable in or in immediate proximity to an intermediate image plane in the optical output to the left eye and/or to the right eye. One diaphragm is arranged eccentrically or concentrically in the installation space of at least one eyepiece or in at least one eyepiece support of the corresponding optical instrument provided therefor. Adjusters are present for positioning and/or adjusting the diaphragms.

Abstract: A multi-mode optical fiber delivers light from a radiation source to a multi-focal confocal microscope with reasonable efficiency. A core diameter of the multi-mode fiber is selected such that an etendue of light emitted from the fiber is not substantially greater than a total etendue of light passing through a plurality of pinholes in a pinhole array of the multi-focal confocal microscope. The core diameter may be selected taking into account a specific optical geometry of the multi-focal confocal microscope, including pinhole diameter and focal lengths of relevant optical elements. For coherent radiation sources, phase randomization may be included. A multi-mode fiber enables the use of a variety of radiation sources and wavelengths in a multi-focal confocal microscope, since the coupling of the radiation source to the multi-mode fiber is less sensitive to mechanical and temperature influences than coupling the radiation source to a single mode fiber.

Abstract: An objective lens assembly 316 to be attached to a surgical microscope includes an objective lens 328, a roll section 318, a pitch section 320, and an attachment mechanism 330. The roll section 318 allows the objective lens 328 to be rotated sideways without causing a pair of eyepieces 324 to move. The pitch section 320 allows the objective lens 328 to be rotated towards and away from the pair of eyepieces 324 without causing the pair of eyepieces to move. A surgical microscope 300 including the objective lens assembly 316 also includes a microscope body 308 and support structure 302, 304, 306, and 310.

Abstract: A microscopy assembly comprises a stand, a stereo microscope supported by the stand, and a mouth switch assembly mounted to a holder, the mouth switch assembly including a mouth piece grippable by a user's teeth, and with a force sensor actuatable by the exertion of pressure by a user's lip while the mouth piece is held by the user's teeth, the force sensor including an actuating element arranged at a side of the mouth piece, wherein an actuating area of the actuating element located next to a front end of the mouth piece is spaced apart from the front end of the mouth piece by a distance larger than 4 mm and smaller than 35 mm.

Abstract: A variable microscope system, which, beginning at the object plane, includes a main lens system, a zoom lens system consisting of several lens groups, and a relay system connected in series to the zoom lens system. In the microscope system, according to the invention, at least one main lens system for infinite mapping of an object is provided and the zoom lens system is designed in such a way that the infinite beam path from the lens system is mapped in an intermediate image, wherein an aperture collimation is provided in a subsequently positioned relay system. An advantage of the microscope system, according to the invention, versus prior art lies in an improved eye pupil adjustment to the illumination as well as to the observation of samples with the contrast method.

Abstract: A tube of a surgical microscope has a base part, intermediate part, pivotable about a rotational axis on the base part, and an ocular part pivotable about a rotational axis on the intermediate part. The imaging beam path is guided through the base part, intermediate part and pivotable ocular part. The tube has a tube lens system which transfers a parallel imaging beam path into an intermediate image. The parallel imaging beam path enters via an opening in a connecting piece of the base part. The tube has a first displaceable mirror element movable about the rotational axis on the base part. The tube has a further displaceable mirror element movable on the intermediate part about the rotational axis. The first mirror element directs the imaging beam path to the further mirror element. The first mirror element and further mirror element are mounted in the imaging beam path between a lens unit having positive refractive power and a lens unit having negative refractive power.

Abstract: An operating microscope has a main objective (1) that extends along an objective plane and is penetrated by a binocular main observer beam path and a binocular co-observer beam path. The binocular main observer beam path has two main observation pupils (3a, 3b) in the objective plane with centers on a first straight line (7). The binocular co-observer beam path has two co-observation pupils (5a, 5b) in the objective plane with centers on a second straight line (9). The first and second straight lines (7, 9) intersect. The co-observer beam path can be displaced with respect to the main observer beam path so that the angle between the second and first straight line (9, 7) changes. The center point (6) between the co-observation pupils (5a, 5b) in the objective plane displaces when there is a change in the angle between the second and first imagined straight lines (9, 7).

Abstract: A device for controlling a surgery microscope during a surgery intervention. The surgery microscope control device is embodied in the form of a bent holder which is arranged, during the use thereof, along a surgeon head from the parietooccipital area through the facial area to a chin area, is provided with means for fixing it to the microscope eye lenses and with supports for interacting with the surgeon head in the nasal bridge, chin, frontal and parietooccipital areas. The support interacting with the chin is provided with an electric switch. In addition, a joystick is mounted on the holder. The device makes it possible to rigidly secure a microscope on the surgeon head during movement, to duplicate the control members mounted directly on the microscope and to not divert the surgeon hands from a surgery for controlling the microscope. The surgery microscope is controlled by means of the head, mouth (lips) and chin of the surgeon.

Abstract: A stereomicroscope of the telescope type includes a first beam path and a second beam path, wherein in the first beam path a first telescope system and in the second beam path a second telescope system are provided, wherein the magnifications of both telescope systems are equal and can be changed synchronously to each other, and wherein a common main objective is allocated to both beam paths. In order to increase the resolution without loss in depth of field, it is proposed that at least one optical element of the first telescope system has, compared to at least one corresponding optical element of the second telescope system, a different optically effective diameter.

Abstract: The surgical microscope system includes a first binocular microscope and a first display device. The first binocular microscope includes an objective lens, a first right ocular lens which provides a first image based on a light flux transmitted through the objective lens, and a first left ocular lens which provides a second image based on a light flux transmitted through the objective lens. The first display device can be disposed opposite to or in alignment with the first binocular microscope, and includes a first right-eye image display surface for displaying the first image and a first left-eye image display surface for displaying the second image. The first display device can be reversed about a horizontal axis extending in a direction along which the first right-eye image display surface and the first left-eye image display surface are located in alignment.

Abstract: An optical gadget is disclosed which in one embodiment is fixed at a location in an orthogonal position on the central optical axis of an operating system, such as a microscope, that may not be truly orthogonal. The gadget includes a hollow tube and a mount for attaching the tube to a control optical axis of an intended orthogonal system such as a microscope.

Abstract: The invention relates to an apparatus and a method for a scanning probe microscope, comprising a measuring assembly which includes a lateral shifting unit to displace a probe in a plane, a vertical shifting unit to displace the probe in a direction perpendicular to the plane, and a specimen support to receive a specimen. A condenser light path is formed through the measuring assembly so that the specimen support is located in the area of an end of the condenser light path.

Abstract: An apparatus for pupil distance adjustment for a binocular tube (22) has two eyepiece carriers (1, 2), at least one of which is mounted rotatably about a rotation axis (3, 4), a threaded spindle (7) being provided which is actuatable for pupil distance adjustment and by way of whose threads (12) the spacing of the two eyepiece carriers (1, 2) is adjustable. The apparatus can be implemented in mechanically simple and compact fashion, and permits accurate adjustment of the pupil distance.

Abstract: Provided is a microscope lens barrel including a collecting lens and a deflecting optical system. The collecting lens emits observation light toward the deflecting optical system. The deflecting optical system includes a first reflecting plane, a second reflecting plane, a third reflecting plane, and a fourth reflecting plane, and deflects the observation light emitted from the collecting lens. The first reflecting plane transmits the observation light incident from one direction and reflects the observation light incident at an angle from another direction. The second reflecting plane reflects the observation light transmitted through the first reflecting plane and makes the reflected observation light incident on the first reflecting plane at an angle. The third reflecting plane reflects the observation light reflected by the first reflecting plane in a direction of the second reflecting plane.

Abstract: A binocular slit lamp microscope for observing a patient's eye, comprises: an objective lens; binocular eyepieces; and a mechanism that includes a plurality of optical systems and is arranged to switch the optical systems to be selectively placed in a predetermined position between the objective lens and the binocular eyepieces on an observation optical path, the mechanism including a variable magnification optical system for changing observation magnification and a viewing angle changing optical system for changing a viewing angle between a right viewing path and a left viewing path.

Abstract: An adjusting device (3) is suitable especially for use on a stand (1) for a surgical microscope (2). The adjusting device (3) makes it possible to move the surgical microscope (2) in a plane (9) perpendicular to the optical axis (8) of the surgical microscope (2). For this purpose, a transmission is provided in the adjusting device (3) which includes a coupling plate which is operatively connected to two force-transmitting elements. When this transmission is moved, at least one of the force-transmitting elements rolls off on the coupling plate. Alternatively, this transmission can be built up as a four-point linkage chain or contain a rhombic mechanism or lever mechanism. It is also possible to configure the transmission with belt elements or to configure the same as an eccentric arrangement having two offset rotation centers.

Abstract: A mouth switch arrangement comprises a mouth switch operable by a mouth of an operator and attachable by a holding device to a base part. The holding device comprises a mouth switch support having a locking member shiftable in a longitudinal direction of a rod of the holding device and a pivot member pivotable about the locking member. The mouth switch is provided for use on a surgical stereo microscope.

Abstract: The invention relates to an apparatus and a method for a scanning probe microscope, comprising a measuring assembly which includes a lateral shifting unit to displace a probe in a plane, a vertical shifting unit to displace the probe in a direction perpendicular to the plane, and a specimen support to receive a specimen. A condenser light path is formed through the measuring assembly so that the specimen support is located in the area of an end of the condenser light path.

Abstract: In an illumination incoupling system for an optical viewing device, illumination incoupling is provided simultaneously into main observer beam paths and assistant observer beam paths using two semitransparent and two fully reflective deflection elements arranged crosswise and symmetrically with respect to the optical axis of the main objective. Homogeneous illumination of the specimen field may thereby be achieved for both the main observer and the assistant observer.

Abstract: A three dimensional microscope system having a microscope and an image processing apparatus for displaying an image by processing an image signal obtained by the microscope, comprises reflecting units which is provided so that first optical paths from an object are approximately symmetric, and objective lens which is provided so that second optical paths from the reflecting units are approximately symmetric, wherein shading data of each part of an image is measured when focal distance of the objective lens to an imaging surface is changed, focal position of the each part being detected, an all-in-focus image about depth of the object being formed in parallel with respect to time based on a pixel having a focused pixel value, contour images of the object being recognized and formed based on each all-in-focus image, and a three dimensional image being formed by synthesizing the recognized contour images.

Abstract: Binocular luminous fluxes are formed by an objective lens and a pair of relay lenses and go through a splitting optical system, which allows an assistant to observe the same stereoscopic view as the surgeon by using an assistant's binocular eyepiece optical system at a location across from the surgeon via a splitting optical system. Part of at least one of the binocular luminous fluxes is incident on a pupil splitting optical system, forming a binocular luminous flux that has undergone pupil splitting, which allows stereoscopic observation by pupil splitting even when the assistant's binocular eyepiece optical system is rotated to the surgeon's side.

Abstract: A microscope, which may be a stereomicroscope, includes: at least one objective; at least one eyepiece; at least one optical component configured to form a beam path from the objective to the eyepiece, where each optical component includes a lens, mirror, or deflection prism; and a tube configured to enclose a portion of the beam path, including at least one region of modifiable length configured to connect to at least one optical correction element and configured so that the optical correction element may be inserted into or removed from the portion of the beam path. The microscope may include a linkage between the tube and the correction lens configured to pivot or slide the correction lens as a function of a length of the region of modifiable length.

Abstract: A flashing dot is alternately shown in the left image and right display of a binocular device at short intervals so as to allow a user to detect the misalignment in the displays. If misalignment occurs, the user sees a dot moving between two locations. The user uses a device or a software program to move the dot for minimizing the apparent movement until a single stationary dot is observed.

Abstract: A stereomicroscope has an objective system, a zoom system, and an eyepiece system. The zoom system consists of two systems that are juxtaposed at the same height. This arrangement reduces the vertical size of a body (2) of the stereomicroscope, allows an observer to easily see a target below the stereomicroscope with the naked eye as and when required, and improves workability when an assistant microscope (7) is attached to the stereomicroscope.

Abstract: A confocal microscope is provided including a confocal imaging system having an objective lens, and a device which can be an attachment to the confocal imaging system, or a part thereof. The device has a housing with an interior cavity and two opposite ends, where one end of the housing receives the objective lens, and at the other end of the housing which is attached to, or is a part of, the housing which forms that other end. The chamber has first and second plates presenting two opposing sides of the chamber, where the first plate lies adjacent the tissue to be treated, and the second plate is attached to the housing. The interior cavity of the housing has a window defining a first volume between the window and the objective lens, and a second volume between the window and the chamber. The first volume has an immersion liquid optically matched to the objective lens, and the second volume is approximately evacuated.

Abstract: The invention provides an objective system for use on a single objective type binocular stereomicroscope which, albeit having a parfocal length thereof shorter than a focal length thereof, can reduce various aberrations as much as possible, and a single objective type binocular stereomicroscope system which can be well manipulated while the viewing position is invariable even when objective lenses are interchanged. The objective system for use on a single objective type binocular stereomicroscope comprises an objective lens for converting light from an object into an afocal light flux and two viewing optical units for receiving light emanating from the objective lens to form left and right images, which satisfies condition: 1.0<FL/L<1.6 where FL is a focal length of the objective system, and L is a distance from a first lens surface of the objective system on an image point side to a sample surface.

Abstract: An operating microscope having an image projecting optical system (9) for introducing an image derived from an endoscopic optical system, which is provided separate from an operating-microscopic optical system, into an eyepiece optical system (18) of the operating microscope so that the operating-microscopic image and the endoscopic image can be simultaneously observed. The image projecting optical system (9) includes a collimating optical system (10), which collimates a beam of rays emergent from the image derived from the endoscopic optical system, and an imaging optical system (13), which forms an image on an image surface of the operating-microscopic optical system provided for observation via eyepiece using the beam of parallel rays emergent from the collimating optical system (10). The imaging optical system (13) is constructed to be movable at least in such a range that its entrance aperture can receive the beam of parallel rays.

Abstract: An optical device and a viewing method having a higher magnification viewing area located substantially centrally in a lower magnification area, whereby the structure facilitates locating viewing object within in higher magnification viewing area.

Abstract: A lens system for a microscope having a variable angle lens-barrel. The lens-barrel includes an afocal optical system lying along an optical path extending from an infinite correction type objective lens to an ocular lens and comprises a first lens group which has positive refractive power, a second lens group which has negative refractive power, and a third lens group which has positive refractive power. The lens system includes a reflective mirror positioned between the second lens group and the third lens group which is mounted for rotation a out a pendular axis. Light through the infinite correction type objective lens becomes a parallel light beam which is passed to the third lens group from the reflective mirror.

Abstract: Disclosed is an optical device with at least one lens and at least one swiveling observation tube, exhibiting the following characteristics: The observation tube comprises a base section fixedly connected to the optical device, and an eyepiece carrier which rolls along an arc of a circle so that swiveling can occur on the base section; a first rotatable deflecting mirror whose rotational axis orthogonally intersects the optical axis of an objective lens of the optical device and which is forcibly rotated by the movement of the eyepiece carrier on the base section; a second rotatable deflecting mirror is arranged in the eyepiece carrier and whose rotational axis orthogonally intersects the optical axis as deflected by the first deflecting mirror and which is forcibly rotated by the movement of the eyepiece carrier on the base section.

Abstract: A stereo-endoscope, by which two perspective views of an objective field are viewed, is provided. A divergent optical arrangement, positioned between the object field and two objective lenses, each of which forms a respective image of the object field, reduces the disparity between corresponding points in the two image fields, where such disparity is caused by distortion of the image formed.

Abstract: A miniature microscope is extremely small, fitting in a palm of a user's hand while providing powerful magnification and enhanced brightness so that the details of an object which cannot be resolved by an unaided eye can be easily seen. The microscope includes a housing have a holder for supporting an object to be viewed. At least one light source is position in the housing off-axis with respect to the object to be viewed. A first prism includes a first prism surface for reflecting light from the light source to a beam splitter surface wherein the beam splitter surface reflects light from the first prism surface to the object to be viewed. The beam splitter surface also passes light reflected from the object therethrough to a second prism. The second prism is positioned with respect to the first prism to provide refraction correction.

Abstract: An observation lens barrel for use in a microscope, comprising a main body for receiving a light beam applied from the microscope and including an image to be observed, an observation optical system provided in the main body and extending at right angles to a direction in which the light beam from the microscope is focused, and optical elements provided in the main body, for receiving the light beam from the microscope and emitting a light beam to the observation optical system. The main body has a first port and a second port. The first port is provided on a side opposing the microscope, with the optical elements located between the first port and the microscope. The second port is provided on a side opposing the observation optical system, with the optical elements located between the second port and the observation optical system.

Abstract: An operating microscope having an image projecting optical system (9) for introducing an image derived from an endoscopic optical system, which is provided separate from an operating-microscopic optical system, into an eyepiece optical system (18) of the operating microscope so that the operating-microscopic image and the endoscopic image can be simultaneously observed. The image projecting optical system (9) includes a collimating optical system (10), which collimates a beam of rays emergent from the image derived from the endoscopic optical system, and an imaging optical system (13), which forms an image on an image surface of the operating-microscopic optical system provided for observation via eyepiece using the beam of parallel rays emergent from the collimating optical system (10). The imaging optical system (13) is constructed to be movable at least in such a range that its entrance aperture can receive the beam of parallel rays.

Abstract: An inverting and reversing prism system for a stereo microscope having an optical longitudinal axis and left and right eye viewing systems having left and right longitudinal axes, respectively, along which left and right beam paths are transmitted, respectively, comprising: at least four reflecting surfaces (13, 15, 16, 13A and 13A, 15A, 16A, 13) in each beam path (14, 14A), two of the reflecting surfaces (13, 13A and 13A, 13) in each beam path comprising inlet and outlet surfaces, respectively, for deflecting the beam path by 90.degree., the inlet and outlet surfaces in each beam path being oriented 45.degree. relative to the optical longitudinal axis of the microscope and 90.degree. relative to each other, with a line of intersection (26) of planes containing the inlet and outlet surfaces in each beam path defining an angle of 45.degree.

Abstract: A stereo microscope arrangement includes an objective used in common, at least a first and a second pair of stereoscopic observation beam paths and an illuminating unit with at least one deflecting element that deflects illuminating light in the direction of the object plane. The illuminating unit is arranged so that it can be mounted in at least two different positions relative to the stereoscopic beam paths. Accordingly, optimized illuminating conditions can be selectively placed at the disposal of the main observer or the co-observer.

Abstract: An apparatus for adjusting a viewing angle of a microscope is disclosed. In a preferred embodiment thereof, a bent eyepiece tube includes a prism on a first optical axis thereof for redirecting an object image to a second optical axis of the tube on which a magnifying eyepiece is aligned. The eyepiece tube is mounted on the microscope for rotation about the first optical axis by a collar, and a spring plunger carried by the tube is biased for respective engagement with a pair of opposing recesses in the collar to releasably secure the eyepiece tube in predetermined rotational positions corresponding to a pair of different viewing angles.

Abstract: An illuminating device for a stereo microscope having an objective with variable imaging focal intercept includes first coupling mechanism, which effects a coupling between the imaging focal intercept of the objective and the likewise adjustable focal intercept of the illuminating optical system, separate from the observation optics, in such a manner that the illuminating focal intercept is in agreement with the imaging focal intercept of the objective. Moreover, adjusting mechanism is provided for the defined adjustment of the diameter of the illuminated field. In particular, the illuminating device is suitable for a surgical microscope.