GB594373A - Improvements in and relating to low power magnifying apparatus - Google Patents

Abstract

594,373. Magnifying - apparatus. HARRISON, G. A. June 12, 1945, No. 14887. [Class 97 (i)] The apparatus comprises a lens mount movable relatively to a support for focusing on an object carried by the support on a stage, which is provided with a mask to prevent direct illumination of the object by a light source positioned below it, the internal surfaces of said mount and support above the object being reflecting, preferably diffusely. As shown the support is a cylinder 1 mounted on a base 2 and apertured for access to a lamp 5, supported on the base and operated by a switch 6. The cylinder has mounted, in a bezel 3a at its upper end, a transparent stage 3, which has painted thereon or secured thereto opaque discs 3b, 3c preventing direct illumination of the object carried thereby, which is viewed through a lens 9, having a dome-shaped mount 8 terminating in a cylinder 7, which telescopes on to the cylinder 1 to facilitate focusing. A cloth 1b around the cylinder 1 stabilizes the focusing position frictionally. Focusing may alternatively be provided for by forming co-operating screw threads on the cylinders 1 and 7. In another embodiment, the mount 8 may be provided with rods slidable for focusing in tubes on the cylinder 1, one rod being displaceable in its tube by a rack-and-pinion or friction disc driving means. The lens mount may be fixed on the base and the support 1 moved for focusing. In each case, the stage 3 may be provided with a projecting lug to facilitate its removal or rotation, and the opaque discs may be replaced by a single disc, which has one black and one white surface and which rests loosely on the stage, or by a translucent sheet when direct illumination is required. Instead of the enclosed lamp 5, daylight or an external lamp may be used, the light from which is reflected on to the stage 3 by a mirror, which may be provided with a lamp socket on a slider so that one or the other may be used as desired. Part of the support may also be cut away to facilitate manipulation of the object on the stage and hand rests may be provided.