Improvements in or relating to ophthalmoscopes / [Henry Lawrence De Zeng].

  • Zeng, Henry Lawrence De.
Date:
1901
Catalogue details

Licence: Public Domain Mark

Credit: Improvements in or relating to ophthalmoscopes / [Henry Lawrence De Zeng]. Source: Wellcome Collection.

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    ( 14,962 A.D. 1901 Date of Application, 23rd July, 1901—Accepted, 31st Aug., 1901 COMPLETE SPECIFICATION. Communicated from abroad by Henry Lawrence De Zeng, of tbe City and County or Philadelphia State of Pennsylvania United States of America. “ Improvements in or relating to Ophthalmoscopes y\ I, George Harrison, Chartered Patent Agent, of the Firm of I). Young & Co., of 11 & 12 Southampton Buildings, London, W.C., 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: — b % invention consists of a novel construction of ophthalmoscope which is adapted for viewing, magnifying, and if desired photographing, the interior of the eye and measuring its refraction by means of telescopic or microscopic, or other similar optical devices applied to an ordinary ophthalmoscope. To the above end my invention consists in the combination with an ordinary 2Q ophthalmoscope such as a reflector with an opening therethrough, of a telescope or microscope (depending upon the relative distance apart of the lenses) co¬ operating with said reflector. The invention also contemplates other features of construction hereinafter more particularly set forth. In the drawings, Figure 1 is a longitudinal section through my ophthalmo¬ scope ; Figure Z a sectional view of a variation; Figure 3 a sec¬ tional view of a portion of another variation, the construction illus¬ trated in Figures 1, 2 and 3 being provided with a source of light carried by the instrument; Figures 4, 5 and 0 illustrate variations where 2() extraneous light is used; and Figure 7 illustrates a portion of the tube showing the graduations whereby the refraction may be measured. In carrying out the invention, A (Figure 1) represents a suitable casing forming the tube of what may be termed a telescope ; B the eye piece prefer¬ ably mounted in a separate tube A1, which is adjustable with relation to the 2 ') tube A; C the objective; D the reflector of the ophthalmoscope, and d the opening therethrough in line with the optical axis of the telescope. The reflector, it will be observed, is placed at an angle of 45 degrees with said axis. Extending from the casing A of the telescope and either made integral there- 30 with or attached thereto is a casing E adapted to contain a suitable electric lamp F, or other suitable source of light. G is a lens located in the casing E, and between the light F and the reflector 1), and acting as a condenser. This lens may or may not be used as desired. Behind the light F is a reflector H, which may or may not be used as desired. 35 On the tube A1, may, if desired, be placed graduations A2 (Figure 7) to indicate the relative adjustment of the telescopic lenses. In Figures 4, 5 and 6, I have shown a variation in the form of the apparatus without departing from the spirit of my invention. In the figures, K represents a suitable plate provided with a handle Iv1. Mounted in this plate K is the 40 ophthalmoscope consisting of a casing M with a reflector X mounted therein, the two provided with an opening m; mounted in the plate K is the tube 0 of the telescope having the objective P (which corresponds with the objective C of . / |'Price 8c/.]