GB439979A - Improvements relating to means or apparatus to be employed in testing or investigating and in maintaining or correcting or remedying and/or developing the power of humanvision - Google Patents

Abstract

439,979. Sight testing and exercising apparatus. SIMPKINS, R. B., 13, Holly Road, Edgbaston, Birmingham. June 21, 1934, No. 18321. [Class 81 (ii)] Apparatus for testing, remedying, or exercising the power of human vision comprises a pair of rectilinear tubes 7, 7a, devoid of optical reflecting or refracting systems, which are capable of movement towards or away from each other whilst remaining parallel and are capable of being set in convergent or divergent planes. In addition, the tubes are capable of being independently elevated or depressed whilst their axes are parallel or at angle to each other. The tubes are mounted on base members 8, 8<a> formed with base plates 8<b> sliding on the upper surface of a box member 9 provided with angle-pieces 10 engaging webs formed on the plates 8<b>. Both the members 8, 8<a> may be movable, or, as shown, the member 8 is fixed, and the transverse movement of the member 8<a> is facilitated by a slotted handle 12 with which a screw 12<c> is associated to lock the member 8<a> in its adjusted position, indicated on a scale 11. Each of the tubes is mounted on its associate base plate by means of an arm 14 rotatable about a pivot 15 which is carried on an arm 16 rotatable about a vertical axis in a member 17 secured to its associated member 8, 8<a>. Additionally each tube carries a screwthreaded member 18 engaging an internally threaded collar 18b mounted on an arm 18<c> secured to a member which slides on a segmental member 8<c> secured to the box and carries a pointer 19 which moves over a scale 9<d>. The pointer carries a slotted arm 19<a> engaged by a screw 19b to secure the tube in its adjusted position. The elevation or depression of a tube is effected by the threaded collar 18b and the adjustment in the vertical direction is indicated by a pointer 14a secured to the arm 14 and moving over a scale 20. The rear end of each tube is fitted with an eye-piece 21 with which may be associated leather or like masks secured to the head of the wearer. Adjacent the eye-pieces 21 are positioned diaphragms 24 formed with holes of varying sizes. The distant end of each tube which telescopes into the tube 7 carries a lamp 27 and is formed with slits in which are placed diaphragms 25 carrying apertures of circular, linear or other shape, and whose angular positions in the tube may be ascertained by graduations 7<g> on the tube. The diaphragms may carry coloured glass, and the apparatus may be mounted in a telescopically adjustable standard.