Abstract: An improvement in a method for closed-chest, video-assisted diagnostic or surgical treatment of a patient is provided. The improvement comprises draping a video monitor with a transparent sterile surgical drape and positioning the draped monitor within the surgical field so that a surgeon can perform an internal surgical or diagnostic procedure and view it on the monitor to provide improved visual alignment for the surgeon. A flexible, sterile drape for covering the video monitor is disclosed. An apparatus for assisting the surgeon in performing closed-chest, video-assisted surgical or diagnostic treatment of a patient is disclosed which comprises a movable cabinet having an adjustable arm to which is affixed a video monitor that can be extended into the surgical field of an operating room to improve the visualization of the surgery performed by the surgeon.

Abstract: An endoscope assembly consisting of an endoscope 622, a light source, 626 and a camera 552 with display 558. The endoscope contains a memory 670 with data that describes the endoscope and its operating characteristics. When the light source is connected to the endoscope with a fiber optic cable 628, the data in the memory are read into a control processor 538a internal to the light source. The control processor, based on the endoscope data configures the light source so that it emits an appropriate amount of light for that endoscope. The light source also sends a control unit 556 of the camera data indicating the type of endoscope to which the camera is attached. Based on this endoscope type data, the control unit processes the image signals generated by the camera head in an appropriate form for the attached endoscope so as to produce appropriate signals for presenting an image on the display.

Abstract: A connector assembly for an endoscope apparatus, which includes a plug removably insertable in a receptacle, is disclosed. The plug has a molded body incorporating a light cable and an electrical connector in a fixed spatial relationship within the molded body.

Abstract: An autoclavable endoscopic optical coupler includes the capability to optically couple an endoscope and a camera, so that a focused image will be communicated to the camera head. Furthermore, the coupler has the capability of withstanding multiple autoclave sterilization treatments without allowing moisture to penetrate the interior. The coupler includes a lens holder assembly that has an endobody on one portion and a second portion that is inserted into and coupled to a coupler body. The coupler body has a camera attached at one of its ends. A focus ring is physically coupled to the coupler body, which is coupled to the lens holder assembly. Turning the focus ring causes a translation motion of the lens holder assembly and endoscope with respect to the camera head.

Abstract: In an organ-region-indication system incorporated in an electronic endoscope system in which an endoscope image is displayed as a motion image on a monitor in accordance with a video signal produced therein, an organ-region-image data base is formed based on an organ map. A plurality of reference data indicating organ-regions and a plurality of image data representing the organ-region are correspondingly stored in the data base. Still image data is retrieved as referential image data from the video signal at suitable regular time intervals. The data base is searched for image data which coincides with the referential image data after the retrieval of the still image data. Corresponding reference data is displayed on the monitor only when the image data, which coincides with the referential image data, is found by the searching.

Abstract: Endoscopes comprise image pickup elements for picking up images and transmission circuits and the like for transmitting the picked up images with radio waves of different frequencies. In addition, bar codes to code the frequencies used for transmission are provided to the respective endoscopes, the bar code provided to the endoscope used in endoscope inspection is read on a receiver side, and a reception frequency of a station selection unit is set to the read frequency, so that a signal obtained by a desired endoscope can be easily received and imaged even in case a plurality of endoscopes are used.

Abstract: A combination laryngoscope and video display for providing images of the area ahead of the laryngoscope to facilitate insertion without damaging the surrounding tissue; the laryngoscope having a detachable blade and a rigid, detachable light and image guide attachment device for providing illuminating light ahead of the blade and for detecting the reflected light.

Abstract: A coupling device for a light and image guiding system that is keyed to prevent incorrect attachment of light and image guides and an interlock that lockingly engages the light and image guides together in an engaged position, the coupling device attached to a portable camera unit that translates optical signals into an electronic format for display.

Abstract: An endoscope to perform non-tethered macroscopy and microscopy at the same time is provided. An electromagnetic source is used to deliver electromagnetic energy through a first optical pathway to a tissue inside a body. An image detector is used to detect the reflected electromagnetic energy from the tissue through a second optical pathway as real-time images. A macro-to-micro lens set is used to change the magnification of the reflected electromagnetic energy before it reaches the image detector with two or more different magnification levels. A filter set is used to filter the reflected electromagnetic energy before it reaches the image detector. Furthermore, the endoscope includes a flexible shaft. The distal end of the shaft includes a spread and spot means to spread and spot the electromagnetic energy at the tissue. A processing means is also included for processing the detected images.

Abstract: An autoclavable endoscope suitable for attachment to a camera while hot. The structure of the endoscope adapted for attachment to the camera lens adapter presents a flat, co-planar proximal face, substantially devoid of grooves and crevices, and minimizes the space between the scope optics and the camera optics, thereby minimizing the volume of hot air that might be trapped between the endoscope and the camera.

Abstract: Endoscopes comprise image pickup elements for picking up images and transmission circuits and the like for transmitting the picked up images with radio waves of different frequencies. In addition, bar codes to code the frequencies used for transmission are provided to the respective endoscopes, the bar code provided to the endoscope used in endoscope inspection is read on a receiver side, and a reception frequency of a station selection unit is set to the read frequency, so that a signal obtained by a desired endoscope can be easily received and imaged even in case a plurality of endoscopes are used.

Abstract: An endoscope is connected optically removably to a TV camera through an adapter. A plurality of fixing pins is arranged on both sides of an insertion axis of an insertion part of the endoscope. A fixing unit to fix the endoscope removably is provided at the front end of an arm unit of an endoscope holder which supports the endoscope movably. The fixing unit has a claw and a movable claw, and grips the fixing pins of the endoscope releasably between the claw and the movable claw.

Abstract: A pill inserted into a body of a patient acquires in-vivo information on the body of the patient. The in-vivo information on the body of the patient is input to a receiver from the pill through a receiving antenna. The pill receives a power-supply signal from the receiver through a power receiving antenna, and a power recovering circuit recovers power from the power-supply signal. A level determining circuit compares the power recovered with a predetermined value to determine the strength of the power-supply signal, and wirelessly transmits the determination result signal to the receiver.

Abstract: An imaging system includes: an optical-system holding member for holding an optical system to form an optical image of a subject; an imaging-device holding member for holding an imaging device to obtain the optical image formed by the optical system; a case for hermetically enclosing the optical-system holding member and the imaging-device holding member; a hermetic connector for hermetically sealing the case, the hermetic connector being electrically connected to the imaging device; a power generator for generating a driving force to move either of the optical-system holding member and the imaging-device holding member; and a driving-force transfer member for connecting the power generator and either the optical-system holding member or the imaging-device holding member to transfer the driving force of the power generator to either the optical-system holding member or the imaging-device holding member.

Abstract: An imaging unit for endoscopes including optical elements for forming an optical image; an imaging device for photoelectrically converting the optical image; a hermetic seal member having at least said optical element and the imaging device incorporated therein; and an imaging device driver making it possible to arbitrarily adjust the position of the imaging device relative to the optical element from outside the hermetic seal member.

Abstract: An operating mechanism for a medical device comprises a photo-interrupter that can designate specified functional operations, an air-tight unit that can accommodate this photo-interrupter air-tightly, a moving member which is disposed inside the air-tight unit, and which moves between a position in which the photo-interrupter designates an operation and a position in which the photo-interrupter does not designate an operation, a coil spring which directly or indirectly biases the moving member to the position in which no operation is designated, an operating member which is disposed on the outside of the air-tight unit, and which can be operated by an operator, and a pair of magnets which transmit a magnetic force that moves the moving member into the position in which an operation is designated against the elastic force of the coil spring in accordance with the operation of the operating member.

Abstract: An endoscopic system for internal inspection of an object includes an endoscope extending along a longitudinal axis between a distal end to be inserted into the object and a proximal end and an illumination assembly attached to the proximal end of the endoscope. The illumination assembly includes a solid-state light source. The endoscopic system also includes an optical system positioned distally from the solid-state light source to receive and convey light to the distal end.

Abstract: A dental camera is provided which is capable of operating in a wireless mode and a wired mode. A handpiece includes circuitry for generating a signal representing a video image and a first connector. A wireless adaptor module includes a power supply for supplying power to the handpiece, a transmitter for transmitting the signal representing a video image, and a second connector that mates with the first connector when the dental camera is being operated in the wireless mode. A cable has a third connector that mates with the first connector when the dental camera is being operated in the wired mode. With this system, clinical flexibility is afforded to a dental practitioner.

Abstract: A coupling device for a light and image guiding system that is keyed to prevent incorrect attachment of light and image guides and an interlock that lockingly engages the light and image guides together in an engaged position, the coupling device attached to a portable camera unit that translates optical signals into an electronic format for display.

Abstract: An endoscope for eye surgery incorporates a handle having a camera and an electric motor driven lens assembly for enabling a user to focus the camera during surgery without manually adjusting the focus. The endoscope includes a probe attached by a rotatable bayonet type connector with a simple pivoting lever to release the probe from the handle. The motor drive system incorporates spring biasing to compensate for overruns of a drive nut on a lead screw when the user attempts to exceed the focal range of the lens assembly.

Abstract: The invention relates to a magnetic drive focusing device with at least one lens within a chamber and an adjuster with magnets outside the chamber. Positioned between the lens and the chamber is a second sleeve with helical guide paths. As the adjuster is moved outside the chamber, the magnetic field within the chamber causes the lens within the chamber to move. As the lens rotates, non-magnetic guides which ride in the helical guide paths force the lens to move axially within the device.

Abstract: A device for positioning components within endoscopic systems includes a hermetically sealed housing. An outer ring element is mounted to rotate about the outer side of the housing and carries on its circumference at least one outer magnet. Further, an inner ring element is mounted inside the housing and carries likewise at least one inner magnet, the magnets being aligned in such a way that any rotation of the outer ring element has the effect to move the at least one inner magnet by magnetic coupling, such movement serving the purpose to position the respective components. In order to achieve a simple, relatively small and functionally safe structure it is proposed that both the outer and inner ring elements be configured as axially displaceable rings carrying the oppositely arranged magnets, and that the inner ring be mechanically connected with the component to be positioned.

Abstract: Endoscopes comprise image pickup elements for picking up images and transmission circuits and the like for transmitting the picked up images with radio waves of different frequencies. In addition, bar codes to code the frequencies used for transmission are provided to the respective endoscopes, the bar code provided to the endoscope used in endoscope inspection is read on a receiver side, and a reception frequency of a station selection unit is set to the read frequency, so that a signal obtained by a desired endoscope can be easily received and imaged even in case a plurality of endoscopes are used.

Abstract: An endoscope system with an endoscope, a TV monitor, and a peripheral device separate from the endoscope and the TV monitor is provided. The endoscope includes an objective optical system and an image pickup device that converts an image formed by the objective optical system into a video signal which can be indicated in the TV monitor. The endoscope also includes a signal generator that generates a control signal to be supplied to the peripheral device so as to control the peripheral device. Additionally, the endoscope includes a transmitter that transmits the video signal to the TV monitor while no control signal is generated by the signal generator. The transmitter also transmits, as a radio signal, both the video signal and the control signal to the TV monitor and the peripheral device upon the control signal being generated by the signal generator.

Abstract: An adaptable, portable hand-held fiber optic camera for producing video images of an object having all of the necessary components for performing fiber optic procedures comprises a power source, a lens system, a light source, and a video camera assembly. The portable fiber optic camera is adaptable to a wide variety of lens systems. The lens system is electrically, removably coupled to the video camera assembly and the light source.

Abstract: The invention provides an endoscope having a scope that takes an image enlarged by driving a movable lens of an optical zoom mechanism by a CCD and displays an image of an object to be observed, wherein a multiplier multiplies RGB color signals by a coefficient set in view of light distribution of illumination light depending on focusing distances of the movable lens, thus eliminating uneven brightness resulting from varying light distribution depending on the focusing distances in enlargement photography. A red component cut filter for cutting a long wavelength side in a red band of the illumination light is provided in a light source unit to improve redness. Further, a coefficient for averaging a brightness signal for a predetermined number of pixels for each horizontal line is calculated, and this coefficient calculation may eliminate unevenness.

Abstract: An endoscope with a coupling device for the connection of a video camera, wherein the endoscope has, at its needle-shaped tube, a distal end which is provided for insertion into the body and a lens system and has a proximal end provided for looking into the endoscope and having a field diaphragm, the coupling device being attached to the proximal end, and wherein a lens system is arranged following the field diaphragm and, like the lens system at the distal end, is sealed off from the outside completely and tightly and is constructed so as to be non-adjustable and non-focusable. The coupling device has no lenses and is adjustable with respect to its axial length in the manner of a telescope.

Abstract: A trocar sleeve capable of holding an endoscopic camera system and an associated endoscopic camera system are provided. When integrated with the trocar sleeve, the endoscopic camera can be used to provide a panoramic overview of the surgical area to supplement the view provided by a main endoscopic camera. The trocar sleeve includes a tube and a base coupled to the tube. The tube includes a channel for accommodating a surgical tool, such as a trocar. The tube further includes a receptacle separate from the channel, for allowing removable attachment of an endoscope to the trocar sleeve. The base includes a fastener for allowing removable attachment of an endoscopic camera head to the trocar sleeve. The camera head has a corresponding fastener for mating with the fastener of the base.

Abstract: The invention relates to a magnetic drive focusing device with at least one lens within a chamber and an adjuster with magnets outside the chamber. Positioned between the lens and the chamber is a second sleeve with helical guide paths. As the adjuster is moved outside the chamber, the magnetic field within the chamber causes the lens within the chamber to move. As the lens rotates, non-magnetic guides which ride in the helical guide paths force the lens to move axially within the device.

Abstract: A stereoscopic endoscope includes a primary optical system for transmitting a luminous flux, reflected by an object located near a first end of the optical system, to a second end of the optical system. A first image forming system forms a first image of the object in accordance with a first area of the luminous flux, and a second image forming system forms a second image of the object in accordance with a second area of the luminous flux, the second area not overlapping the first area. An imaging device detects the first image and the second image, the image detecting system outputting an image signal.

Abstract: An imaging apparatus in which an imaging head having an observation hole for intaking images of an object to be observed formed at a top end is exchangeably mounted to a main body having an imaging device and an illumination light source wherein the imaging head is provided with a plurality of optical fibers for guiding a light from the illumination light source and illuminating the same to the object, light incident ends of respective optical fibers are disposed at positions opposing to emission ends of the illumination light source, and the light emission ends are circularly disposed around the image pick-up optical axis, whereby an appropriate illumination light in accordance with a magnifying ratio can be illuminated without disposing an illumination light source such as of LEDs to an imaging head such as an exchangeable lens unit.

Abstract: An autoclavable endoscope suitable for attachment to a camera while hot. The structure of the endoscope adapted for attachment to the camera lens adapter presents a flat, co-planar proximal face, substantially devoid of grooves and crevices, and minimizes the space between the scope optics and the camera optics, thereby minimizing the volume of hot air that might be trapped between the endoscope and the camera.

Abstract: A coupling provides mechanical, light-guiding, and image-guiding connection of an endoscope to a camera module. It is proposed that a first cylindrical stem, in whose interior a proximal end segment of the light guiding system is received, project in the coupling direction from a coupling end of the endoscope. Also projecting from the coupling end in the coupling direction is a second approximately cylindrical stem whose length and diameter are greater than the length and diameter of the first stem, a proximal end segment of the image guiding system being received in the interior of the second stem. The second stem coacts with an interlock arranged on the camera module, for mechanical interlocking of the coupling. The first and second stems extend at a distance next to one another, and the coupling end of the camera module has receptacles, complementary to the two stems, into which the two stems penetrate.

Abstract: According to a remote operation support system, a physician present in a remote place can view endoscopic images displayed in an operating room over a communication line, and change an image area or a viewing direction represented by endoscopic images in a desired manner by performing manipulations. The physician present in the remote place can thus support an operator present in the operating room. An endoscope system installed in the operating room and a remote control system installed in a control room located in the remote place are linked using a public communication line. The endoscope system has a signal transmission apparatus installed in the operating room. The signal transmission apparatus in the operating room converts a video signal and a control signal or patient data, which are produced by a CCU and a system controller respectively, and outputs resultant signals over the public line. The remote control system has a signal transmission apparatus installed in the control room.

Abstract: An apparatus and technique for compensating the display of an image obtained from a video camera system associated with an endoscope as it is moved through various orientations are described. The received optical image is converted to an electrical signal with an image sensor that can be a CCD or a CMOS detector. The endoscope video camera system has an inertial sensor to sense rotations of the received image about the optical axis of the endoscope and the sensor's output signals are used to rotate either the image or the image sensor. In case of rotation of the image sensor the rotation sensor can be a gyroscope or a pair of accelerometers. In case of a rotation of the image obtained with the image sensor the inertial sensor, which can be an accelerometer or a gyroscope, the image is rotated within a microprocessor for subsequent viewing on a video display.

Abstract: An endoscope for eye surgery incorporates a handle having a camera and an electric motor driven lens assembly for enabling a user to focus the camera during surgery without manually adjusting the focus. The endoscope includes a probe attached by a rotatable bayonet type connector with a simple pivoting lever to release the probe from the handle. The motor drive system incorporates spring biasing to compensate for overruns of a drive nut on a lead screw when the user attempts to exceed the focal range of the lens assembly.

Abstract: An apparatus and technique for compensating the display of an image obtained from an endoscope as it is moved through various orientations are described. The endoscope received optical image is converted to an electrical signal with an image sensor that can be a CCD or a CMOS detector. The endoscope has an inertial sensor to sense rotations of the received image about the optical axis of the endoscope and the sensor's output signals are used to rotate either the image or the image sensor. In case of rotation of the image sensor the rotation sensor can be a gyroscope or a pair of accelerometers. In case of a rotation of the image obtained with the image sensor the inertial sensor, which can be an accelerometer or a gyroscope, the image is rotated within a microprocessor for subsequent viewing on a video display. The signal processing to achieve compensatory rotations of the displayed image as an operator of the endoscope moves it about is described.

Abstract: An apparatus is provided comprising a transmitter unit for detecting the position of a medical instrument with the aid of a CAS system, wherein the apparatus comprises the transmitter unit at a fixed position and wherein the medical instrument is attachable to the apparatus. To allow simple assembly and disassembly, the apparatus is formed as an adapter. A reception coupling is provided on one first side of the adapter at which the adapter can be releasably, however mechanically fixed and simply coupled to a predetermined coupling location on the medical instrument.

Abstract: An endoscope, in particular a video endoscope, has an endoscope shaft at the distal end and a mount at the proximal end for attaching an optical imaging device, for example a video camera, and an endoscope housing between said endoscope shaft and said mount, said mount being rotatable relative to said endoscope shaft, via a rotary joint, about the longitudinal axis of said endoscope an optically imaging arrangement, which is at least partially positionally displaceable by way of an adjusting device for focusing the image transmission, moreover being received in said endoscope housing. Said endoscope housing is configured in continuously hermetically sealed fashion, and said rotary joint is arranged outside said endoscope housing.

Abstract: A manual instrument for medical and dental diagnostics having an instrument housing (5). An examination sensor (3) is exchangeably mounted on the proximal end, and an image display device (4) is mounted on its distal end. The image display device (4) has a screen (9) and at least one lighting device (23) with a tension source (22) and light transfer means, as well as a means for image creation is located within the image display device (4). The image display device (4) is swivel-mounted on the instrument housing (5) around a vertical axis (8) extending perpendicularly to the longitudinal symmetrical axis (7) of the manual instrument (2).

Abstract: An endoscope having an autoclavable replaceable sealed optical assembly without moveable parts. The sealed optical assembly is placed into an insertion tube of the endoscope. A focusing device is attached to the proximal end of the sealed optical assembly. The opposite end of the focusing device may be connected to an appropriate image-receiving device such as a CCD camera. The endoscope differs from conventional optical devices of this type in that its focusing is performed by shifting the image-receiving plane of the CCD camera with respect to an immobile plane of a image produced by optical elements of the sealed optical assembly.

Abstract: A video camera head configured for use with an endoscope and having a conductive inner chamber for shielding the imager and imager electronics from electro-magnetic interference is described in which the inner chamber is substantially isolated from contact by a human or conductive fluid through a sealed outer non-conductive housing. Another aspect of the invention involves hermetically sealing the inner chamber, thus facilitating the use of steam autoclave sterilization, including flash sterilization, to sterilize the camera head.

Abstract: A method for producing an endoscopic drape includes positioning a portion of a sheath of flexible material (22) in abutment with a joining portion (23) of a first housing piece (14). A joining portion (24) of a second housing piece (16) is positioned close to joining portion (23) and the joining portions are then joined together, for example, by ultrasonic welding. This forms a housing (12) in which the portion of the sheath (22) is entrapped between the first housing piece (14) and the second housing piece (16). The portion of the sheath (22) may be joined to the first housing piece (14) by a thermoplastic gasket or o-ring (35) prior to joining the first and second housing pieces (14, 16) to improve the seal between the sheath (22) and the housing (12). The housing (12) includes a clear lens or window (27) that provides an optical pathway through the housing and also provides a sterility barrier.

Abstract: The present invention is an improved apparatus and method for providing variable-angle endoscopic views in a cavity, such as an internal cavity in a human patient. The apparatus includes an elongated tubular portion with a viewer at its proximal end and a reflector assembly at its distal end. The reflector assembly includes a first reflector and a second reflector, with the second reflector rotationally mounted to permit its rotation about an axis generally aligned with an optical path portion passing from the first reflector to the second reflector. The viewer is preferably a camera rotatably secured to the apparatus. A rotator controls rotation of the second reflector and the camera, so that rotation of the second reflector causes a corresponding rotation of the camera. The assembly thus permits near-spherical viewing of the cavity without requiring substantial movement of the endoscope.

Abstract: A stereoscopic endoscope system includes a combined system of a stereoscopic endoscope unit and a camera unit. The stereoscopic endoscope unit has an insertion part and an observation part. The insertion part includes an objective lens and a relay lens in order from an object side, where the objective lens has a pair of first optical system and a second optical system which are arranged in parallel in an insertion direction, and a third optical system arranged in the insertion direction. The first optical system and the second optical system are for a stereoscopic vision observation, and the optical system has a viewing angle larger than that of the first and the second optical systems for observing a wider range than a that of the stereoscopic vision observation. The relay lens is arranged on the camera unit side of the objective lens.

Abstract: In one embodiment, an imaging unit to be mated with an image-producing scope via a coupler includes at least one imaging unit body, and an image sensor disposed within the at least one imaging unit body. The imaging unit further includes a refractive lens movably disposed within the at least one imaging unit body, and at least one first component adapted to receive an output from a focusing mechanism disposed on a body of the coupler. The at least one first component is configured and arranged so that movement of the focusing mechanism with respect to the coupler body causes the lens to move within the at least one imaging unit body to focus an image produced by the scope onto the image sensor. In another embodiment, a method for operating an imaging system including an image-producing scope, a refractive lens, and an image sensor involves providing a coupler that is free of the refractive lens.

Abstract: The illuminating light transmitted by the light guide inserted through the elongate inserted section is projected out of the distal end surface of the inserted section. The illuminated objects pass through the respective non-superimposed pupils of the two objective lens systems arranged in parallel within the distal end section of the inserted section and their images, which are not equal to each other are formed on the focal surface. The respective images are transmitted to the rear side by one common relay lens system having a single optical axis. The transmitted final images are formed respectively on the image taking surfaces of the image taking devices. The respective images photoelectrically converted by the respective image taking devices are processed to be signals, are displayed in the monitor and are stereo-inspected through shutter spectacles.

Abstract: An improved focusing coupler device for coupling the image capturing portion of an endoscope to a video camera is disclosed. The coupler device includes a housing having an elongate internal chamber defining an optical pathway for connecting the optical image paths of the endoscope and the camera, first and second windows closing off the opposite ends of the chamber, a lens transport assembly disposed in the chamber for relative movement between the ends of the chamber, the lens transport assembly comprising a lens carrier that defines a longitudinal series of rack gear teeth and is movable between the opposite ends of the chamber, and at least one focusing lens mounted to the lens carrier in coaxial alignment with the longitudinal axis of the chamber.

Abstract: An improved adaptor for coupling a video camera to an endoscope, borescope, or the like includes a focusing mechanism and an independent zoom or magnification variation adjustment mechanism. The zoom mechanism will move two lens groups along an optical path simultaneously, but at different speeds. Each lens groups preferably includes a pair of lenses affixed together as a doublet. By controlling the position of the doublets relative to a pair of focusing lenses, the present adaptor provides an optically compensated zoom mechanism which allows changes in the magnification of the adaptor throughout a wide magnification range without having to refocus the adaptor.

Abstract: An adaptor for coupling a video camera to an endoscope, borescope, or the like includes a focusing mechanism and an independent zoom or magnification variation adjustment mechanism. The zoom mechanism will move two lens groups along an optical path simultaneously, but at different speeds. Each lens groups preferably includes a pair of lenses affixed together as a doublet. By controlling the position of the doublets relative to a pair of focusing lenses, the present adaptor provides an optically compensated zoom mechanism which allows changes in the magnification of the adaptor throughout a wide magnification range without having to refocus the adaptor.