Abstract:
An optical assembly comprising a microscope (1) including a binocular (3) with a pair of oculars (4, 5), an optical body (8) and an objective lens (9) and an optical path; and an endoscope (2) provided with an extension (10), an outlet ocular (16) and an optical path. A commutating modulus (12, 13, 14; 18, 19, 14) is disposed between the binocular (3) and the optical body (8) of the microscope, and the outlet ocular (16) of the endoscope (2) as to enable an observer whose eyes are located at each ocular (4, 5) of the microscope (1) to observe selectively either: (a) the optical path of the microscope (1), or (b) the optical (or electronic) path of the endoscope (2), or (c) both optical paths simultaneously to scan an object to be investigated.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a microscope-endoscope assembly which is especially useful in surgery. 
     Considerable developments have been made during the last years in many fields of surgery. Surgeons have to use increasingly sophisticated devices for either diagnostic or therapeutics purposes. 
     In certain fields, those skilled in the art use two kinds of devices, i.e. on the one hand a microscope and, on the other hand an endoscope, each having its own unique function. For instance, a typical example wherein these two devices are used is ophthalmic surgery. 
     Typically, the microscope provides a user with a plan view determined by the intra-ocular members without any possible views of angular areas; i.e. a profile view cannot be provided. 
     The endoscope allows both angular areas to be viewed and therapeutic means to be introduced. 
     The use of one device, e.g. the microscope, followed by the use of the other, i.e. the endoscope, does not facilitate accurate determinations or orderly surgical procedures which, of course, are desired. When the microscope and endoscope are used in sequence, the surgeon must alternately look through both oculars of each device. But, this is not easily done and does not enable certain operations to be carried out. 
     There is a need for a device which enables a surgeon to observe and work while keeping his eyes on the oculars of a single device. 
     OBJECTS OF THE INVENTION 
     It is an object of the present invention to satisfy the aforesaid need. 
     Another object is to provide a compact assembly which enables a surgeon to perform those operations which may be required while keeping his eyes on the oculars of a microscope. 
     A further object is to facilitate three kinds of observations to be carried out by means of the inventive apparatus: 
     In a first position, the surgeon or the user uses the optical path of the microscope. 
     In a second position, the surgeon uses the optical path of the endoscope while looking through the microscope oculars. He does not have to move about and his free hands may be used as necessary. This is important in certain particular fields, such as in ophthalmic surgery where it is known that the endoscope is manipulated in a manner analogous to that of a pencil to orient it in any particular direction needed to obtain a desired good observation. 
     In a third position, the surgeon looks through the oculars of the microscope along both respective optical paths of the microscope and of the endoscope, and both paths are merged as to provide a single superposed image. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention relates to an assembly comprising, on the one hand, a microscope having a binocular, an optical body and an objective, and, on the other hand, an endoscope provided with an extension and an outlet ocular, the assembly including a commutating modulus placed between the binocular and the optical body of the microscope and the outlet ocular of the endoscope to enable an observer whose eyes are located at each ocular of the microscope to selectively observe either the optical path of the microscope or the optical or electronic path of the endoscope (if the endoscope is of the electronic type) or simultaneously both the optical path of the microscope and the optical or electronic path of the endoscope to scan the object to be investigated. 
     As an aspect of the present invention, the commutating modulus is removable and is comprised of at least one optical separator and a reflecting device having their respective normals aligned with the bisectrix between the incident beam and the direction of the respective optical axes; 
     the distance between the separator and the reflecting device is equal to 1/√2a is the axis gap, i.e. the distance between the optical axes of both optical paths of the microscope; 
     the separator is a glass slab having one face subjected to a semi-reflecting treatment and the reflecting device is a mirror; 
     the optical means of the endoscope are adapted to that of the microscope by using a dioptric or catadioptric optical system which dimensionally and positionally brings into accord both images formed by the endoscope and the microscope; 
     the endoscope comprises an outlet ocular providing an image focused for infinity and the microscope provides an image focused for infinity, these images being projected in the space gap between the optical body and the binocular; 
     the commutating device comprises an internal reflecting prism, a separating cube formed of two prisms and an opaque screen, all being retracted by means of a driving motor; 
     in one embodiment the dioptric or catadioptric optical system is formed of an air medium; 
     in another embodiment the dioptric or catadioptric optical system is a mirror; 
     and in a further embodiment the dioptric or catadioptric optical system is a combination of convergent and divergent lenses of a reflecting prism; 
     the opaque screen is a metal sheet painted to be light-opaque. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various advantages and features of the present invention will appear from the following detailed description with reference to the accompanying drawings in which: 
     FIGS. 1A and 1B are a general diagrammatic view of the assembly of the invention; 
     FIG. 1C is a schematic representation of the position relation of the optical members of the commutating modulus; 
     FIG. 2 shows an embodiment comprising a relatively small number of optical members; 
     FIG. 3 is an alternative embodiment of the device shown in FIG. 1A; 
     FIG. 4 is another alternative embodiment of the assembly of the invention; 
     FIG. 5 is a vertical cross-section of an embodiment adapted to retract the commutating modulus; and 
     FIG. 6 is a partial plan, partial cross-sectional view of the device shown in FIG. 5. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     In the accompanying drawings, wherein identical parts are indicated by the same reference symbols and numerals, the microscope is designated by 1 and the endoscope by 2. 
     As is conventional, the microscope comprises a binocular 3, an optical body 8 and an objective 9. The subject to be investigated is represented by reference numeral 15. The microscope 1 has two oculars 4 and 5 and internal prisms 6 and 7. The endoscope comprises an extension 10 which transmits an outlet image of the endoscope to the inlet of an adapting optical device, i.e. to an outlet ocular 16 of the extension. A supporting ring 11 holds the outlet ocular 16 of extension 10 of endoscope 2 at a desired position. 
     On FIGS. 1A, 1B, a commutating modulus comprises a mirror 12, a separator 13 and an opaque screen 14. The separator 13 is a glass slab having a surface which has been previously subjected to a semi-reflecting treatment as represented by dotted lines. The distance between the separator 13 and the mirror 12 is related to the gap a which is the distance between the optical axes of the two optical paths of the microscope leading to oculars 4 and 5. The distance between the separator 13 and the mirror 12 is preferably equal to 1/√2a. Generally, the mirror is a plan mirror and the separator is a dioptric slab with parallel sides. 
     In addition to the distance parameter between the mirror and separator, the orientation thereof comprises a second parameter. 
     As illustrated in FIG. 1C, the mirror 12 and the separator 13 are so oriented that each of their respective normals 28 and 29 constitutes the bisectrix of the respective angles α and β between the incident optical beam i coming from the endoscope 2 and the direction of the respective optical axes AOG and AOD leading to oculars 4 and 5. The optics of endoscope 2 and of its extension 10 are adapted to the optics of the microscope 1. To this end, use is made of a dioptric or catadioptric optical system which positionally and dimensionally brings into accord the images provided by endoscope 2 and microscope 1. 
     In the example shown in FIGS. 1A and 1B, this optical system merely consists of an air medium. In this configuration, the air medium is an optical system having a focal magnitude of 1. The endoscope 2 includes an outlet ocular 16 which provides an image focused at infinity whereas the microscope 1 also provides an image focused at infinity within the space gap between optical body 8 and binocular 3. FIG. 1B differs from FIG. 1A in that extension 10 in FIG. 1B includes an optical fiber 10&#39; and does not consist solely of lens and prism assemblies as in FIG. 1A. 
     The supporting ring 11 may be adjusted as desired by the user under the particular conditions of use. 
     On FIGS. 1A and 1B, the opaque screen 14 is deliberately located under the separator 13 to mask the right optical path, i.e. that of the separator. With the modulus in the illustrated position, the surgeon may observe subject 15 via the endoscope. Alternatively, when the commutating modulus assembly is retracted, the surgeon can observe subject 15 via the optical path of the microscope. Movement of the modulus to provide this masking effect is preferably provided by any suitable means and may be actuated by means of a pedal to enable the surgeon to use his hands for any other useful operation. 
     FIG. 2 illustrates a practical embodiment of the present invention. Here, the commutating modulus comprises an internal reflecting prism 18, a separating cube 19 formed of two prisms 20 and 21 and the opaque screen 14. 
     Prisms 18, 20 and 21 are reflecting prisms. Both prisms 20 and 21 are, for example, secured to each other to form the cube, and have undergone a semi-reflecting treatment. This commutating modulus is driven by an electric motor 17 for retracting some or all of the members 18, 19, 14. When the entire assembly is retracted, the user who looks through the oculars 4 and 5 is able to observe the subject by way of the microscope. If desired, the opaque screen 14 may also be retracted separately. 
     The position of extension 10 of endoscope 2 with respect to microscope 1 shown in FIG. 2 is facilitated by the use of a divergent lens 23, a convergent lens 24 and a reflecting prism 22 mounted between lenses 23, 24. By way of example, the divergent lens 24 is provided with a -50 focus, the convergent lens 23 is provided with a 100 focus and the assembly is afocal with a magnitude of 0.5. 
     In the embodiments shown in the drawings, these positions are provided: 
     In the first position, the commutating modulus is not retracted and the user looks through both oculars 4 and 5 of microscope 1 along the optical path of the endoscope. 
     In the second position, the commutating modulus assembly is retracted, and the user looks through both oculars 4 and 5 along the optical path of the microscope. 
     In the third position, only the opaque screen 14 is retracted, and the user may observe through both the microscope path and the endoscope path which coincide to provide a single image, as in a mixed image. 
     On FIG. 3, an alternative embodiment is illustrated, wherein use is made of a mirror 25 located in front of the outlet ocular 16 of the extension 10 of endoscope 2. This permits outlet ocular 16 to be disposed in the illustrated configuration. 
     FIG. 4 illustrates the provision of photographic fittings 26 and video apparatus 27 which may be mounted upwards of the optical body 8. 
     A displacement operation of the commutating device of the present invention is described with reference to FIGS. 5 and 6, wherein the commutating apparatus includes internal reflecting prism 18 and the separating cube comprising two prisms 20 and 21. The reflecting prism and separating cube are mounted on a carriage 34 which is adapted to slide transversely with respect to a frame 35 on which are secured two parallel columns 36, 37. Guiding on column 37 is ensured by means of co-axial sleeves 38, 39 (FIG. 6) rigidly fixed to the base of carriage 34; and guiding on column 36 is ensured by a bracket 40 (FIG. 5) also rigidly fixed to the base of carriage 34. 
     A rack mechanism 41 is secured to a side of carriage 34 above sleeves 38, 39 and column 37 and in parallel to the axis of column 37. A reversible electric motor 17 affixed to frame 35 at one side of carriage 34 rotatably drives an output shaft 42 on which is fixed a pinion 43 whose teeth mesh with those of the rack mechanism 41. Thus, when pinion 43 is rotatably driven in either direction by motor 17, the carriage 34 and the optical members supported thereon are moved in a corresponding direction along columns 36 and 37 and between two locations: one being in the optical path of the endoscope and the other being retracted from the optical path of the endoscope. The carriage 34 has a window 44 at the side opposite to the motor 17. 
     The opaque screen 14 is slidably mounted on gliders provided in the base of the carriage 34 and may be retracted at will when it is desired to look through the optical paths of the microscope. 
     The electric supply to the motor is switched off when the carriage 34 reaches either of its extreme positions on the frame 35. Either sleeve 38 or sleeve 39 actuates an end-of-travel switch comprising a lug 46 or 47 mounted at the end of a resilient arm 48 or 49 sidely projecting from the motor 17. The deformation or motion of the resilient arm actuates a micro-switch 50 or 51 coupled to the motor to control current supplied thereto.