An improved ophthalmoscope / [Henry Rosborough Swanzy].

  • Swanzy, Henry Rosborough.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: An improved ophthalmoscope / [Henry Rosborough Swanzy]. Source: Wellcome Collection.

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    Date of Application, 9th Nov., 1892 Complete Specification Left, 8th Aug., 1893—Accepted, 4th Nov., 1893 PROVISIONAL SPECIFICATION. An Improved Ophthalmoscope. Henry Rosborough Swanzy A.M. M.B. F.R.C.S.I. Examiner in Ophthalmic Surgery to the University of Dublin and to the Royal University of Ireland 23 Merrion Square Dublin, and George Prescott 9 Merrion Row Dublin, Electrical Engineer and Optician do hereby declare the nature of this invention 5 to be as follows :— The indention is an improved ophthalmoscope in which is combined various mechanical and optical contrivances some of which have been used in other instruments but have here been simplified in detail in such a manner as to produce an instrument of the highest efficiency at a low price. The instrument consists of two 10 reversible mirrors attached to one side of a plate, on the other side of which is a disc with lenses circumferentially arranged, the high efficiency of the instrument is attained by having the lenses as close as possible to the mirrors, the accentuation of the position of each lens is attained by a simple pin without any separate spring, additional lenses are provided in a small rotatable piece moving concentrically with the disc. 15 The handle of ebonite is attachable without any metallic terminal, and the case is of vulcanite. Dated this 5th day of November 1892. HENRY ROSBOROUGH SWANZY. GEORGE PRESCOTT. 20 COMPLETE SPECIFICATION. An Improved Ophthalmoscope. Henry Rosborough Swanzy A.M. M.B. F.R.C.S. Examiner in Ophthalmic Surgery to the University of Dublin and to the Royal University of Ireland 23 Merrion Square Dublin, and George Prescott 9 Merrion Row Dublin 25 E.E. and Optician, do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement:— Our invention is an improved ophthalmoscope in which is combined various mechanical and optical contrivances some of which have been used on other 30 instruments but have here been simplified in detail in such a manner as to produce an instrument of the highest efficiency at a low cost. The instrument consists of two mirrors of the usual reversible order attached to one another by cementing them back to back to an intermediate plate, and secured in the usual manner to one side of another plate screwed to the handle of the instrument. On the other side 35 of this plate is a rotatable disc with lenses circumferentially arranged so that each in its turn may be brought opposite the hole in the mirrors. The high efficiency of the instrument depends upon the reduction of the diffraction to a minimum, and this is chiefly attained by eliminating the usual spring catch, for holding each lens in its turn opposite the hole in the ophthalmoscope, and using instead a simple 40 projecting pin, without any projecting spring, for accentuating the positions of the lenses, thus allowing the plate between the lenses and the mirrors to be as thin as the strength of the material will allow and so bringing the lenses and mirrors close together. The drawing shews at Fig. 1 the disc A with the lenses circumferentially arranged. 45 a one of the lenses, h small countersinkings or c nicks, into which a catch, shewn \Price 8d.]