Patent GB-880708-A (GB)
Title: Apparatus for microscopic examination
IPC: G21F7/06
Filed: 1958-01-17
Abstract: 880,708. Viewing equipment for radioactive environment. REICHERT OPTISCHE WERKE A. G., C. Jan. 17, 1958 [Jan. 19, 1957], No. 1715/58. Class 39(4) [Also in Group XX] In apparatus for the microscopic examination of specimens emitting radio active radiation a microscope is mounted within a protective chamber while an illuminating device consisting of a lamp and a condenser, and a device for viewing the image formed by the microscope objective are located outside the chamber. Also outside the chamber are means for electrically and/or mechanically operating microscope control elements disposed within the chamber. The inverted microscope 1 is mounted within a protecting lead chamber 7 and includes an objective changer 58, carrying several objectives 4a, and a specimen stage 2 for a specimen 3. This specimen is illuminated by a lamp 11 and condenser 12 disposed outside the chamber 7, and via afocal systems 15 an image of the lamp 11 is formed at 9. An image of the specimen 3 formed by the operative objective is relayed by an afocal system 17 to an eyepiece, projection screen, or camera disposed at 19 outside the chamber 7. The microscope stage 2 is rotatable by an electric motor 22, which is coupled to a shaft 25 geared at 26 to the stage 2. This stage is also mounted on cross slides so as to be movable in orthogonal directions by electric motors 21, 21a. Control of these motors is effected via a switchbox 28, Fig. 2, disposed outside the chamber 7 and, for each movement, three pairs of contacts are provided which are successively closed to light signal lamps indicating that the stage has reached the initial, midway and final positions in its movement. On reaching the final position, the operative motor is automatically switched off. Fine and coarse adjustment. Rotation of a spindle 33 from outside the chamber 7 operates a drive shaft 35, Fig. 1, having a pinion engaging a rack on the stage support so that the stage is raised and lowered. Fine adjustment is effected by rotating a spindle 36 geared to a shaft 38 which serves to raise and lower the support carrying the objective which is in use. Diaphragm adjustments. The aperture diaphragm, field diaphragm, and bright and dark -field diaphragm are operated by pulleys 39, 40 and 41 respectively driven by belts from pulleys on parallel shafts 44, 45 and 46 which extend outside the chamber 7. A slide for an annular diaphragm is controlled by a push rod 43a. The shafts 44, 45, 46 and the push rod 43a are mounted in a bracket 47, Fig. 1, secured by a support 48 on the base plate. This support also carries a bracket 49 having a dovetailed guide 50 in which is slidable a member 51 carrying a rotatable polariser, the member 51 being movable by a push rod 52. Rotation of this push rod operates a rack to rotate the polariser. Objective changer. In a guide in a support 53, fixed to the base. a slide 55 is movable by a push rod 56. This slide 55 carries an orthogonal guide 57 in which is provided a slide 58 movable by rotating a shaft 59, having a pinion meshing with a rack on the slide. Slides 60 are accommodated in the slide 58, these slides 60 carrying alternative objectives 4a. A change of objective is effected by first pushing the rod 56 to bring the slide 58 close into the microscope. The rod 59 is then turned to bring a free space in the slide 58 into alignment with a guide on the objective holder of the microscope. A rod 62 is then moved axially until a bayonet joint thereon engages the slide 60 of the objective then in use. When such engagement is complete the movement of the rod 62 is reversed so as to bring this objective into the free space on the slide 58. The shaft 59 is then again rotated to bring the slide 60 carrying the objective next to be used into line with the guide on the objective holder of the microscope. This objective is then pushed into this guide by means of the rod 62.