Abstract: A specific value for the magnification factor to be achieved for a specimen image is input to observe the specimen through a microscope. An optical system magnification factor and an electronic zoom magnification factor are calculated so as to achieve this specific value. When there are a plurality of optical systems with varying magnification factors, the optical system that achieves the calculated magnification factor is inserted at an observation optical path. When outputting image signals by capturing an image of the specimen formed by the optical system, the specimen image is obtained at the electronic zoom magnification factor that has been calculated. As a result, it is possible to obtain an image of the specimen which achieves a magnification factor determined in conformance to the product of the magnification factor of the optical system and the electronic zoom magnification factor.

Abstract: An inverted microscope of the present invention comprising a microscope main body including a relay optical system which forms a primary intermediate image of a sample by a light from the sample irradiated with an irradiation light via an objective lens and an image forming lens, and which relays a light flux from the primary intermediate image, and a light path switch unit which is disposed in the microscope main body to be attachable/detachable, and which branches the light flux relayed by the relay optical system.

Abstract: Focusing systems for which variation of magnification with focus is either inherently compensated, or is calibrated and corrected. The required conditions for inherent compensation are determined, and the desired state is called constant relative magnification. It is shown that telecentricity does not guarantee constant relative magnification. Both telecentric and non-telecentric accessory cameras for endoscopes are disclosed that have constant relative magnification, as are additional optical systems for general metrological purposes. Methods for calibrating change in relative magnification and deviation of the optical axis with focal shift are disclosed, as are methods for incorporating these changes into perspective dimensional measurements. Embodiments are disclosed in which only a single quantity need be measured to perform the correction, and these embodiments require only a low-resolution position transducer to provide accurate measurements.

Abstract: In order to provide a microscope episcopic illumination device and a microscope therewith having simple structure, having an aperture diaphragm and a field stop, and being capable of setting optimum light source magnification in accordance with change of an image surface size required for from eyepiece observation to TV observation. The microscope episcopic illumination device has a light source, a collector lens, an aperture diaphragm, a light source image forming lens portion for forming an image of the light source in the vicinity of the aperture diaphragm, pupil relay lens groups for re-forming the image of the light source formed in the vicinity of the aperture diaphragm in the vicinity of a pupil surface of an objective lens, and a field stop. The lens portion is a lens system with a variable finite focal distance, and varies a projection magnification of a ratio of the re-formed image of the light source in the vicinity of the pupil surface to the light source by changing the focal distance thereof.

Abstract: A specimen of transparent living material is covered over with a cover glass while being observed. An optical image of this specimen captured by an objective lens includes spherical aberration due to the cover glass. The spherical aberration included in the optical image is corrected by a correction optical system. Imaging is performed while varying this spherical aberration correction amount. From the plurality of images which have been imaged, an image is selected whose spherical aberration is the least, according to increase and decrease of contrast. Imaging is performed while driving the correction optical system so as to bring the spherical aberration correction amount to be equal to that when the selected image was imaged.

Abstract: There is disclosed an inverted microscope comprising an objective lens disposed under a sample, a tube lens which is disposed in a light path of an observation light emitted from the objective lens and which forms the observation light into an image, an incident light illumination optical device which is disposed between the objective lens and the tube lens, and which introduces incident light illumination into the light path of the observation light, and an input/output port which is disposed between the incident light illumination optical device and the tube lens, and which splits a light flux from the light path of the observation light or introduces the light flux into the light path of the observation light.

Abstract: A microscope is disclosed that includes: a light source that emits light in a wavelength range that includes both visible and infrared wavelengths, an illuminating optical system for illuminating a specimen with the light from the light source, an objective lens for gathering light from the specimen and causing it to converge, a light beam dividing unit that divides the beam of light from the objective lens into plural divided light paths such that the wavelength ranges in the divided light paths differ from one another, a magnification conversion optical system in one of the divided light paths which converts the magnification of images formed by light in that divided light path, and an imaging device located in each of at least two of the divided light paths, wherein the objective lens has a magnifying power less than or equal to 32 and a numerical aperture greater than or equal to 0.80.

Abstract: A variable dark-field illumination method and apparatus to produce microscopic and macroscopic images with a variable dark-field effect thereby making best use of various detector response characteristics. The variable dark-field of the invention is particularly characterized by an adjustable object contrast which optimizes the use of the various detectors dynamic range. The invention is particularly useful when coupled with a video camera and for macroscopic systems having a large depth object field. The dark-fields of the art have geometries which are objectionable because those geometries have very limited depths of field. The invention is particularly distinguished from the art as the dark-field methods and apparatuses of the art are generally geometrically restrictive and they do not provide variable contrast control for input images.

Abstract: A durable, heat treatable layer coating system of at least 10 layers including from the substrate outwardly: SnOx wherein x is <2.0, TiOx wherein x is <2.0 (or NiOx wherein x is less than 1.0), silver, NiOx wherein x is less than 1.0, SnOx wherein x is <2.0, TiOx wherein x is <2.0 or NiOx wherein x is less than 1.0, silver, NiOx wherein x is less than 1.0, SnOx wherein x is <2.0, and Si3N4 as an overcoat.

Abstract: An optical element change-over control apparatus comprises an optical element change-over member capable of holding a plurality of optical elements and rotating alternatively to locate a specific optical element on an optical path. A driving element serves to rotate the optical element change-over member. A positioning detecting element detects the selected optical element being positioned so that the optical element stays in a predetermined position on the optical path, and outputs positioning signals. An origin detecting element detects the point of origin of the optical element change-over member.

Abstract: The stereoscopic microscope includes a common close-up optical system that faces an object, a pair of zoom optical systems that form a pair of primary image, a pair of field stops, a pair of relay optical systems that relay the primary images to form a pair of secondary images, an inter-axis distance reducing element, an image taking device and an illuminating optical system. The object light rays incident on the close-up optical system form the primary images having predetermined parallax at the field stops through the zoom optical systems. The inter-axis distance reducing element reduces the inter-axis distance of the right and left light rays. The primary images are re-imaged by the relay optical systems as the secondary images on the adjacent regions on the single image taking surface of the image taking device, respectively.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: The invention relates to a changeover system for optical components such as filters, reflectors, polarizers and lens systems in optical equipment, particularly microscopes, a so-called reflector revolving nosepiece. The elements carrying the optical components, the so-called reflector blocks, are held by spring force against precision stops on the revolving nosepiece. For this purpose, the reflector blocks have lateral flanges that are respectively held against precision stop surfaces on the revolving nosepiece, by two respective leaf springs. The direction of the spring forces is mutually inclined, so that an outer edge of the flange is pressed into the interior edge formed on the revolver by two mutually perpendicular surfaces. The invention makes possible a rapid and simple fitting and changeover of reflector blocks without the use of tools.

Abstract: An inverted microscope comprises an image output port that forms an image of an observation sample to the external surface facing to an observer, at the front side of a microscope main body, below an observation tube to which eyepieces are attached, and photographing devices configured that one of at least two kinds of photographing devices is selectively attachable/detachable to the image output port.

Abstract: The observation apparatus of the present invention has a basic structure as a normal microscope with an objective system constituted by an interchangeable objective unit attached to a revolver and a tube lens unit fixed at a position to which a light beam is guided from the objective unit. Particularly, the observation apparatus has a mechanism capable of setting a special optical system (auxiliary lens unit) constituting part of the objective unit on the optical axis of the objective system between the revolver and the tube lens unit. A partial objective unit constituting part of the objective unit is attached to the revolver to constitute the objective unit by the partial objective unit and the auxiliary lens unit. In this manner, the objective unit for a very low magnification whose total length is larger than the parfocal distance for the objective in this apparatus can be constituted.

Abstract: An infrared imaging microscope, particularly of the type used to carry out FT-IR measurements, is provided with an assembly (40) which can be moved into or out of the beam propagating to the microscope detector (32) in order to change the magnification provided by the optical elements of the microscope. The assembly (40) can be located between the objective Cassegrain mirror (18) and the intermedite focus position (42) of that mirror. In one example the assembly includes first and second spherical mirrors (44, 45). The assembly can be mounted so as to be rotatably movable between its positions in or out of the beam.

Abstract: A microscope is disclosed that includes: a light source that emits light in a wavelength range that includes both visible and infrared wavelengths, an illuminating optical system for illuminating a specimen with the light from the light source, an objective lens for gathering light from the specimen and causing it to converge, a light beam dividing unit that divides the beam of light from the objective lens into plural divided light paths such that the wavelength ranges in the divided light paths differ from one another, a magnification conversion optical system in one of the divided light paths which converts the magnification of images formed by light in that divided light path, and an imaging device located in each of at least two of the divided light paths, wherein the objective lens has a magnifying power less than or equal to 32 and a numerical aperture greater than or equal to 0.80.

Abstract: The apparatus for objective changing comprises an inventory of at least one objective (5) which defines a longitudinal axis (6). The objective change between an objective storage position (22) and a reference objective position (5a) is made possible by the apparatus, and the reference objective position (5a) lies within an optical beam path that defines an optical axis (3). A retaining element defines the reference objective position (5a), and during the objective change, the objective (5) with its longitudinal axis (6) is movable, in the vicinity of the retaining element (26), substantially coaxially with the optical axis (3). The objective change is accomplished along a guide rail (17).

Abstract: A microscope with an exchangeable intermediate tube that is inserted between the microscope objective and an ocular eyepiece instead of the tube lens and which is adjustable in a defined manner with respect to its height and has relay or transfer optics with an essentially constant intersection length, comprising, in the observation direction, a first lens group with a long focal length, preferably greater than 10 m, and a second lens group with a short focal length whose common focal length corresponds to the focal length of a standard tube lens, preferably approximately 164 mm, wherein the distance between the first and second lens group is adjustable.

Abstract: A stereoscopic microscope comprising a uniaxial optical system consisting of an objective lens system and a vari-focal optical system which is coaxial with the objective lens system, and at least a pair of observation optical systems, wherein right and left optical axes of the observation optical systems pass through locations different from that of an optical axis of the uniaxial optical system and wherein the uniaxial optical system comprises a positive lens component made of an extraordinary dispersive optical material.

Abstract: A microscope apparatus includes an objective lens, an imaging lens, a pupil relay lens, and an image relay lens. The primary image of a specimen is formed between the imaging lens and the pupil relay lens, and the image of the pupil of the objective lens is projected between the pupil relay lens and the image relay lens so that a pupil modulator is disposed at the position of the projected pupil image. This arrangement makes it possible to produce pupil modulation, observe various specimens, and set the optimum position of an eyepoint.

Abstract: An afocal zoom lens comprising, in order from an object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power and a fourth lens group having a negative refractive power; the second lens group being movable in a fixed direction from the object side to an image side and the third lens group being movable in a fixed direction from the image side to the object side at the time of the zooming of from the low magnification end state to the high magnification end state. The afocal zoom lens fulfills specific conditions. The afocal zoom lens has a zoom ratio of 14 magnifications or higher and has a good optical performance. Also disclosed is a microscope having such a lens.

Abstract: A video-type stereoscopic microscope is composed of a close-up optical system which emits object light rays from an object as parallel rays, a pair of zoom optical systems which converges the object light rays having passed through different parts of the close-up optical systems and a relay optical system which relays images formed by the respective zoom optical systems to a CCD. Zoom lens barrels which hold the respective zoom optical systems individually are fixed in a zoom housing such that the position thereof can be adjusted in the axial direction. This zoom housing is fixed in a casing of the stereoscopic microscope such that the position thereof can be adjusted in the direction of the optical axis of the close-up optical system.

Abstract: A microscope suitable for use together with MRI, and a support stand for the microscope are provided. A microscope 1 is a non-magnet type where any electric motor is not used, and hence does not induce fluctuations of magnetic field having effects on image quality of an MRI 3 by focusing or zooming. Hence, the microscope of the invention is suitable for use together with MRI 13. Since a clutch C is of non-magnet type, a support stand 2 does not induce changes in the surrounding magnetic field environments if the clutch is operated, and hence it is suitable for use, for example, in proximity to the MRI.

Abstract: An adapter lens for a Greenough-type stereomicroscope (SM1), the adapter comprising a negative lens group (4) and a positive lens group (5) along an optical axis (AX3). The adapter lens attaches to the objective lens side of the Greenough-type stereomicroscope. Variation of the distance (D54L, D54H) between the positive and the negative lens group allows an operator of the stereomicroscope to position the eye pieces (8 and 8′) of the stereomicroscope to a comfortable height for ease of use.

Abstract: A microscope with incident light input coupling, wherein the light provided for the incident illumination is directed onto the partially reflecting layer of a beam splitter cube and is directed from there through the objective onto the specimen, while the light reflected and/or emitted by the specimen travels back to the partially reflecting layer and passes through the latter into the imaging beam path. In a microscope of this type, the beam splitter cube is provided with a negative spherical curvature at its outer surface facing the objective. Further, instead of the conventional tube lens, there is a combination formed of a converging lens and a diverging lens, wherein the surface curvatures of the converging lens and the diverging lens and the negative spherical curvature effected at the beam splitter cube are adapted to one another in such a way that the back-reflections of the incident illumination in the intermediate image plane are limited to a minimum.

Abstract: A stereoscopic microscope comprising an objective lens system and a variable magnification optical system which are disposed coaxially with each other in addition to an eyepiece optical system, and configured so as to permit stereoscopic observation of an image of an object by leading, to right and left eyes of an observer by way of the eyepiece optical system, rays having passed through portions apart from optical axes of the objective lens system and the variable magnification optical system. This stereoscopic microscope has a length as measured from the observer's eyes to the object to be observed which is shortened by disposing at least two reflecting members in the variable magnification optical system for bending an optical path in the variable magnification optical system.

Abstract: An inverted microscope has a microscope base, a stage, an observation optical system having an objective lens, a stage support member which is arranged on the microscope base and supports the stage at two ends, and a change member which can change the level position of the stage with respect to the microscope base.

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: 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 computerized control and display system for a stereo microscope is disclosed. The objective lens is selected for a minimum and maximum magnification range and then two sets of movable lenses within the stereo module are positioned through computer control to achieve a precisely desired magnification. In the preferred embodiment, a lookup table is used to smoothly select the proper position of the two movable lenses in relationship to one another as the magnification is either increased or decreased. A stereoscopic image is transmitted by cameras to a computer screen with the use of a wireless eyewear/shutter system cycling at 120 cycles per second for viewing.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: A stereomicroscope is capable of interchangeably fitting low- and high-magnification objective lenses. A transmission illumination unit thereof includes a light source, a shield element for cutting off partially light beam, first and second condenser lenses for converging the light beam passing the shield element, and a mechanism for selecting one of the first and second condenser lens and disposing the selected lens on the optical axis. The first condenser lens sets a position conjugate to an entrance pupil of the low-magnification objective lens in a position of the shield element. The second condenser lens sets a position conjugate to an entrance pupil of the high-magnification objective lens in the position of the shield element.

Abstract: A high-magnification objective optical system for binocular stereomicroscopes, each having two observation optical systems for forming light from an object into left and right images through an objective lens, is provided with an optical member placed to be removable or replaceable between the object to be observed and the objective lens and satisfies the following condition: 0.2<|NA·m|<1.2 where NA is a numerical aperture on an object side of the objective lens and m is the magnification of the objective lens. In this way, a stereoscopic observation is obtained, holding good performance of image formation at high magnification and NA.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: A variable optical delay element that is physically compact introduces time delays to an applied optical signal. The variable optical delay element includes a pair of substantially parallel members, each having a linear reflective surface facing the reflective surface of the other member. An input lens secured to a first end of the first linear member collimates an optical beam launched by an input fiber while an output lens secured to a second member focuses the collimated optical beam onto an optical output fiber. A first actuator adjusts the offset relationship between the members in a direction parallel to the pair of members to designate the number of reflections of the collimated optical beam by the reflective surfaces before being received by the output lens. A second actuator adjusts the distance separating the linear reflectors. The optical signal is delayed by a predefined time interval by adjusting the offset positions of the members and the distance separating the members.

Abstract: In a microscope such as for the examination of specimens in specimen vessels, a device for changing objectives is provided. The microscope includes at least a first objective. The device comprises an arrangement for providing an operating control so that the at least first objective can be raised and lowered vertically and is displaceable horizontally vertical to an optical axis of the microscope.

Abstract: An observation optical apparatus includes an objective unit; the first path splitting member placed on the optical axis of the objective unit for splitting an optical path from the objective unit into two; the first optical system situated on one of two optical paths split by the first path splitting member, for forming an image at least twice; the first observation device-located at the imaging position of the first optical system; the second optical system situated on the other of the two optical paths, having a higher total magnification and a larger numerical aperture than the first optical system; the second observation device located at the imaging position of the second optical system; and a stop for low magnification, placed at the pupil position of the first optical system, for reducing the numerical aperture.

Abstract: For focusing an operation microscope within a defined focusing range, a main objective and parts of an illuminating device are arranged in a focusing module that is separate from the microscope body. The focusing module is movable along the optical axis in a defined manner by means of manual or motor drives, so that focusing on a desired object detail is possible. Desired fine focusing can thus take place, in addition to coarse focusing by spatial positioning of the operation microscope by means of a stand. The advantages are a compact design, prevention of reflections through the main objective, and widely varied possibilities for filling of additional accessories.

Abstract: In a microscope with an objective, a variable magnification system and an autofocus arrangement, the autofocus arrangement produces a projection beam path for the projection of an autofocus marking onto an observation object, and an imaging beam path which passes through an objective, for imaging on a detector the autofocus marking projected onto the observation object. The projection beam path and/or the imaging beam path then passes through the variable magnification system outside its optical axis.

Abstract: A revolver assembly of a microscope, for switching a current objective lens to one of a plurality of lenses by manual rotary operation of the revolver assembly, includes a revolver main body and a revolver rotary section rotatably coupled to the revolver main body for removably mounting thereon a plurality of objective lenses of the microscope. A holding member extends in a direction crossing a rotary axis of the revolver rotary section, and is immovable with respect to the revolver main body. A manually operable rotary operation section is arranged approximately parallel to the rotary axis of the revolver rotary section, and is coupled to the holding member so as to be manually rotatable around an axis which is separated from the rotary axis of the revolver rotary section by a predetermined distance.

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: A stereoscopic microscope comprising an objective lens system and a variable magnification optical system which are disposed coaxially with each other in addition to an eyepiece optical system, and configured so as to permit stereoscopic observation of an image of an object by leading, to right and left eyes of an observer by way of the eyepiece optical system, rays having passed through portions apart from optical axes of the objective lens system and the variable magnification optical system. This stereoscopic microscope has a length as measured from the observer's eyes to the object to be observed which is shortened by disposing at least two reflecting members in the variable magnification optical system for bending an optical path in the variable magnification optical system.

Abstract: A microscope apparatus includes an objective lens, an imaging lens, a pupil relay lens, and an image relay lens. The primary image of a specimen is formed between the imaging lens and the pupil relay lens, and the image of the pupil of the objective lens is projected between the pupil relay lens and the image relay lens so that a pupil modulator is disposed at the position of the projected pupil image. This arrangement makes it possible to produce pupil modulation, observe various specimens, and set the optimum position of an eyepoint.

Abstract: A wide-angle viewing attachment for an ocular microscope includes a first lens attached to the microscope and a second lens independently mountable with respect to the microscope. The second lens is positionable proximal to an eye of a surgical patient and is maintained in the proximal position by an attachment system including a support member coupled in a fixed position to an operating table on which the patient is reclined. A first support rod extends vertically from the support member and a clamp member is adjustably mounted on the support rod. A horizontally extending second support rod is adjustably coupled to the clamp member and terminates at one end in a generally flat plate. A lens carrier includes a spring clamp for holding the second lens and a support arm extending generally horizontally with respect to the first support rod. The carrier terminates in a magnet assembly which holds the lens carrier to the flat plate.

Abstract: A confocal microscope equipped with a light source, a rotary disk having holes, a highly sensitive image receiver or camera, an immersion lens, and a contact endpiece for contacting the skin and in which is engaged at least a lower part of the lens. The endpiece includes a central opening and abuts the skin about the central opening. The microscope allows for relative axial displacement of the contact endpiece relative to the lens.

Abstract: A super wide-angle variable magnification viewfinder includes an objective lens group of a positive refractive power. The objective lens group further includes a fixed first lens unit of a negative refractive power, a movable second lens unit of a negative refractive power for compensating the change of a view angle, a movable third lens unit of a positive refractive power for changing the magnification of the optical system, and a fixed fourth lens unit of a positive refractive power. Also included in the finder is a prism for erecting an image and an eyepiece lens group of a positive refractive power. The objective lens group forms an actual image of an object, and the actual image can be observed through the eyepiece lens group. The view finder satisfies the condition:1.75<L.sub.t /f.sub.T <1.87where f.sub.T is the focal length of the objective lens group at the telephoto position, and L.sub.t is the distance from a first lens surface of the objective lens group to a focus.

Abstract: An automatic focus detection device for microscopes includes an optical system for forming an image of a sample; an image sensor for photoelectrically converting an optical image derived from the optical system; a device for storing image data such that an electric signal obtained from the image sensor is converted from analog to digital form and for processing the image data to compute contrast values; a device for comparing the contrast values; a device for moving an objective lens or a stage for the sample; and a device for storing the position of the objective lens or the stage.

Abstract: A microscope lens guide system is disclosed wherein a plurality of lens carriers are magnetically biased to guide rods to ensure rectilinear motion of lenses held by the carriers along an optical axis of the microscope. In a first embodiment, each lens carrier includes a first portion having a passage for slidably receiving a guide rod and a second portion having a magnet for biasing the second portion for engagement with another guide rod formed of magnetic material. In a second embodiment, additional magnets are provided to bias the passage for engagement with the guide rod received by the passage.

Abstract: A microscope includes an objective lens and 1st, 2nd, 3rd and 4th magnification-varying optical systems of a same power, having optical axes parallel to the optical axis of the objective lens and positioned behind the objective lens and around the optical axis thereof. An objective unit houses the objective lens and the 1st, 2nd, 3rd and 4th magnification-varying optical systems. A deflection optical system directs two specified light beams, among the light beams transmitted by the 1st, 2nd, 3rd and 4th magnification-varying optical systems, to a first direction and also directs the remaining two light beams to a second direction. A first observation optical system respectively forms images, for observation, by the two light beams directed to the first direction. A second observation optical system respectively forms images, for observation, by the two light beams directed to the second direction. First and second observation units are detachably mountable alternatively to the objective unit.