US1158187A - Ophthalmological instrument. - Google Patents

Ophthalmological instrument. Download PDF

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US1158187A
US1158187A US9903A US990315A US1158187A US 1158187 A US1158187 A US 1158187A US 9903 A US9903 A US 9903A US 990315 A US990315 A US 990315A US 1158187 A US1158187 A US 1158187A
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reflector
light
lens
instrument
eye
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US9903A
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Henry L De Zeng
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/02Subjective types, i.e. testing apparatus requiring the active assistance of the patient
    • A61B3/028Subjective types, i.e. testing apparatus requiring the active assistance of the patient for testing visual acuity; for determination of refraction, e.g. phoropters
    • A61B3/04Trial frames; Sets of lenses for use therewith

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  • ZuNc at tate of New Jersey, have invented a new and useful Ophthalmological Instrument, of which the following is a specification.
  • M invention relates to a new and useful opht almological instrument and consists in providing a plurality of reflectors suitably arranged for directing the light from the objective lens to the eye piece with means for increasing or decreasing the focal range and the power of the instrument.
  • Fig. 4 is a sectional view on line w:v Fig. 3.
  • Fig. 5 is a sectional view on line y-gy Fi '3.
  • Fig. 6 is a sectional view of a portion 01: the device in detached position.
  • Fig. 8 is an elevation on a reduced scale
  • Fig. 9 represents a side elevation of a prism or reflector which may be employed.
  • 1 designates the casing of any suitableform or constructlon, forming the body portion or the support for the operating mechanism, and 1 which is adapted, when applied to an ophthalmoscope, to be connected with the tube 2 thereof, which latter is adapted to be mounted upon the handle 3, which carries a source of l ght 4, such as an electric lamp, the said tube 2 carrying a lens 5.
  • a sight opening 6 which may or .may not be provided with a lensor eye plece, and, as here shown, the said sight opening 6 is located adjacent the upper portion of the casing 1 and at one side of the center thereof.
  • a reflector 7 designates a reflector of any suitable construction, here shown as a'prism, which is suitably mounted in the casing with respect to the sight opening 6 in order to direct light thereto.
  • the, said lens 8 is located ad- Jacent the upper'portion of the casing at one side of the center thereof.
  • a reflector here shown as a I prism, suitably mounted within the casing with respect to the objective lens 8, in order to receive the light therefrom and to direct thesame in a suitable manner.
  • a third reflector here shown as a double reflecting prism, which is suitably positioned within the casing in order to receive the light from the reflector 9 and to directthe same to the reflector 7 whereby it will be understood that the light from the objective lens 8 will be in a suitable and proper manner directed by the reflectors to the sight opening 6 or eye-piece of the instrument.
  • the reflector 9 will direct the central incident ray at right angles to the central incident ray from the object, while the reflector 10 will direct the light first at right angles with its central incident ray and then parallel with its primary incident'ray to the reflector 7 which willdirect its central incident ray at right angles therewith to the sight opening 6 or eye-piece of the instrument.
  • ab e means is provided for increasing or decreasing the focal range of the instrument by increasing or decreasing the distance over which the light will travel in passing from the objective lens to the eye-piece, and, as here shown, I have mounted the double reflector 10 in a suitable support '11, which is adjustable or movably mounted within the casing 1 in any suitable or desired manner, and has a pointer or indicating mechanism -12 connected therewith, here shown as ex tending through the slot 13 in a wall of the casing 1, to be suitably positioned with re spect to a series of indications 14, in order that an indication may be had of the adjustment'made of the focusing of the instrument upon objects at various distances.
  • the said reflector 10 is movably mounted with respect to the other two reflectors, in order that by moving the same toward or away from the said reflectors 7 and 9, the distance over which the light'will travel in its transit or passage .from the objective through the instrument to the eye-piece, will be increased oidecreased, thus adjusting the focal rangeof the instrument, it being understood, however, that any suitable means for ac'c-oinplishing this adjustment, may .be employed.
  • disk I mount a disk'15 in suitable relation with respect to the sight opening 6, in which disk I are mounted a suitable number of lenses 16,
  • the instrument when used as-an eye testi'ng'device, it may be provided "with an objective lensand an ocular lens of substan'. tially the same power, and for the purpose one of the ocular lenses of the disk 15 may 'beemployed orthe ocular lens may be mounted at the sight opening, as previously ployed' for yieldingly h0ld%?7% stated. Any suitable means may be emthe desired lens in operative position.
  • I provide a reflecting device, such as a mirror 17 suitably mounted or carried upon the. casing lin proper position to receivethe light from the light source I 4 and direct the same to the object. Any
  • suitable form of reflecting device may be employed, and as here shown, I have provided a construction, wherein the reflecting device is provided with the two reflecting surfaces 18 and 19 offset with respect to each Suitother in order to provide the sight opening 20, through which the object may be viewed.
  • the operator places his eye in line with the sight opening 6 and with the reflecting device 17 directing the light upon the object.
  • the casings may be moved toward or away from each other,.in the direction indicated by the arrows in Eig. 8, .to-properly locate the sight opening with respect to the eyes'of the operator, after which the set screws may be tightened to. hold the casing in proper position.
  • the reflectors 10 of eachcasing may be suitably connected bymeans of a rod 23 which has suitable connection therewith, in order to allow for the adjustment of the casings 1, and which rod 23 is in threaded engagement with an adjusting screw 24, whereby the adjustment of the said reflectors 10 is accomplished.
  • Fig. 9 I have shown a form of prism which may be employed, if desired, wherein instead of mounting the lens 8 as shown in Fig. 1, independent of the prism or reflector, a lens 25- is carried thereupon and may be located upon either face of the prism, if desired, but in either case, the operation and effect will be substantially the same since the objective 8 may be positioned, so that the light will pass it before reaching the reflector 9 or after being reflected therefrom.
  • the scale 14 isgraduated in ophthalmic lens or dioptric measurements, and willtherefore indicate any lens equivalent which may be necessary for the correction of errors of refraction in the eye under examination. It
  • I have devised'a new and useful optical instrument embodying an objectiveflens and an alternate eye-piece, and a plurality of re-1 fiectors, with means for increasing or decreasing the focal range and the magnifying power of the instrument
  • I have mounted the objective lens and eye-piece in suitable relation to each other, and have provided means adapted to direct the light from one lens to the other in a manner which erects the image and gives an upright position to the object when viewed through the instru ment.
  • an objective lens In an ophthalmological instrument, an objective lens, a reflector coiiperating therewith, an eye lens, a reflector eoiiperating therewith, a third reflector lcot'iperating with the first and second mentioned reflectors, means for increasing or decreasing the distance which the light will travel in passing from the objective lens to the eye lens, and means for indicating theincrease or decrease of light travel in ophthalmic lens values.
  • an objective lens In an ophthalmological instrument, an objective lens, a reflector suitably positioned with respect thereto, an ocular lens of substantially the same focal power as said ob-' jective lens, a reflector suitably positioned with respect thereto, and a third reflector suitably positioned to reflect the light from the first-mentioned reflector to the secondmentioned reflector and movably mounted to increase or decrease the distance the light will travel in passing from the objective to theiocular lens, and means for indicating the" increase ordccrease of light travel in ophthalmic lens values.
  • an indicating means coiiperating with a dioptric scale for indicating the nature of the light rays emanating from the eye-piece.
  • a support In an ophthalmologicalinstrument, a support, a reflecting device carried thereby for directing light to the object, an objective lens suitably supported with relation to said reflecting device, a reflector for said objective lens, a sight opening, a reflector for said sight opening, means for directing the light from one reflector to the other redoctor, said means being adjustable with respect thereto, an ophthalmic lens-scale for determining the amount of adjustment of the light directing means, and a series of lenses suitably mounted tovbe brought into alinement with said sight opening.
  • a body portion a source of light, a reflector adapted to direct light from said light source to the oba source of light, a reflector adapted to direct light from said light source to the object, a lens and a reflector enacting therewith, a second lens and a reflector coacting therewith, a third reflector for-directing the light from the first to the second mentioned reflector, and movable means carrying the third reflector for focusingthe instrument for the correction of errors in the refraction of the observed eye, said means indicating substantially the required corrective lens values.
  • a source of light a reflector adapted to diltd rect light from said light source to the object, a lens and a reflector coacting therewith, 'a second lens and a reflector coacting therewith, a third reflector for directing the light from the first to the second mentioned reflector, means movably supported by the body portion and carrying the third reflector for focusing the instrument, and means for indicating the amount of the focusing adjustment in ophthalmic lens values.

Description

H. L. DE ZENG. OPHTHALMOLOGICAL INSTRUMENT.
APPLICATION FILED FEB. 23. I915.
Patented Oct WITNESSES HENRYL. DE znne, or MAPLE snaps, new JERSEY.
OPHTHALMOLOGIG-AL INSTRUMENT.
1,158,187. original application filed January 11,
To all whom it may concern: Be it known that I, HENRY I1. DE
a citizen of the United States, residin Maple Shade, county of Burlington,
ZuNc, at tate of New Jersey, have invented a new and useful Ophthalmological Instrument, of which the following is a specification.
This applicationis a division of the application for Letters Patent No. 1562, filed by me January 11, 1915, for an optical instrument. l
M invention relates to a new and useful opht almological instrument and consists in providing a plurality of reflectors suitably arranged for directing the light from the objective lens to the eye piece with means for increasing or decreasing the focal range and the power of the instrument.
It further consists of other novel features of construction, all as will be hereinafter fully set forth.
It will be understood that my invention I is adapted for use with any ophthalmological ranges are necessary or desired, so that the 1 same is equally adapted for such instruments as an ophthalmoscope,- binoculars, range finders, telescopes, optometers, or other similar instruments. In the drawings, I have shown the same as particularly applied to an ophthalmoscope and I have shown a construction of one form of a binocular, but it will'be evident that, as
I above stated, the invention is adapted to other instruments and that the arrangement of the parts may be varied, other lnstru' casing with oneplate removed. Fig. 4 is a sectional view on line w:v Fig. 3. Fig. 5 is a sectional view on line y-gy Fi '3. Fig. 6 is a sectional view of a portion 01: the device in detached position. Fig. diagrammatic view, showing the passage of the light from one reflector to the other.
instrument wherein difi'erent focal- 7 is a man:-
Specification of Letters Patent.
Patented Unit. 2%, 1915.
1915, Serial No. 1,562. Divided and this application filed February at, 1915. &ria1 No. 9,903. v
Fig. 8 is an elevation on a reduced scale,
showing the invention in the form of a b nocular. Fig. 9 represents a side elevation of a prism or reflector which may be employed.
lmilar numerals of reference indicate corresponding parts in the figures.
Peferring to the drawings, 1 designates the casing of any suitableform or constructlon, forming the body portion or the support for the operating mechanism, and 1 which is adapted, when applied to an ophthalmoscope, to be connected with the tube 2 thereof, which latter is adapted to be mounted upon the handle 3, which carries a source of l ght 4, such as an electric lamp, the said tube 2 carrying a lens 5. In the rear face of the casing 1 and at a suitable point therem, I provide a sight opening 6, which may or .may not be provided with a lensor eye plece, and, as here shown, the said sight opening 6 is located adjacent the upper portion of the casing 1 and at one side of the center thereof.
7 designates a reflector of any suitable construction, here shown as a'prism, which is suitably mounted in the casing with respect to the sight opening 6 in order to direct light thereto. i
8 designates an objective lens suitably mounted upon the side of the casing 1 opposite to that of the sight opening 6 and preferably out of alinement therewith, and, g
as here shown, the, said lens 8 is located ad- Jacent the upper'portion of the casing at one side of the center thereof.
9 designates a reflector, here shown as a I prism, suitably mounted within the casing with respect to the objective lens 8, in order to receive the light therefrom and to direct thesame in a suitable manner.
10 designates a third reflector, here shown as a double reflecting prism, which is suitably positioned within the casing in order to receive the light from the reflector 9 and to directthe same to the reflector 7 whereby it will be understood that the light from the objective lens 8 will be in a suitable and proper manner directed by the reflectors to the sight opening 6 or eye-piece of the instrument.
As will be understood more particularly from the diagrammatic view of Fi 7, the reflector 9 will direct the central incident ray at right angles to the central incident ray from the object, while the reflector 10 will direct the light first at right angles with its central incident ray and then parallel with its primary incident'ray to the reflector 7 which willdirect its central incident ray at right angles therewith to the sight opening 6 or eye-piece of the instrument. ab e means is provided for increasing or decreasing the focal range of the instrument by increasing or decreasing the distance over which the light will travel in passing from the objective lens to the eye-piece, and, as here shown, I have mounted the double reflector 10 in a suitable support '11, which is adjustable or movably mounted within the casing 1 in any suitable or desired manner, and has a pointer or indicating mechanism -12 connected therewith, here shown as ex tending through the slot 13 in a wall of the casing 1, to be suitably positioned with re spect to a series of indications 14, in order that an indication may be had of the adjustment'made of the focusing of the instrument upon objects at various distances. .From the above, it will be understood that the said reflector 10 is movably mounted with respect to the other two reflectors, in order that by moving the same toward or away from the said reflectors 7 and 9, the distance over which the light'will travel in its transit or passage .from the objective through the instrument to the eye-piece, will be increased oidecreased, thus adjusting the focal rangeof the instrument, it being understood, however, that any suitable means for ac'c-oinplishing this adjustment, may .be employed.
gIn order to focus or increase or decrease the magnifying powersof the instrument,
' when used as an opthalmoscope or otherwise,
I mount a disk'15 in suitable relation with respect to the sight opening 6, in which disk I are mounted a suitable number of lenses 16,
of different power, and whereby said lenses maybe successively brought into alinementwith said sight opening, as'wlll be evident. -"When the instrument is used as-an eye testi'ng'device, it may be provided "with an objective lensand an ocular lens of substan'. tially the same power, and for the purpose one of the ocular lenses of the disk 15 may 'beemployed orthe ocular lens may be mounted at the sight opening, as previously ployed' for yieldingly h0ld%?7% stated. Any suitable means may be emthe desired lens in operative position. en employed 7 as'an ophthalmoscope, I provide a reflecting device, such as a mirror 17 suitably mounted or carried upon the. casing lin proper position to receivethe light from the light source I 4 and direct the same to the object. Any
suitable form of reflecting device may be employed, and as here shown, I have provided a construction, wherein the reflecting device is provided with the two reflecting surfaces 18 and 19 offset with respect to each Suitother in order to provide the sight opening 20, through which the object may be viewed.
In the operation of the device as an ophthalmoscope, it will be understood that the operator places his eye in line with the sight opening 6 and with the reflecting device 17 directing the light upon the object. The
light therefrom will pass through the opening 20 to the objective lens 8 to the reflector 9, will pass downwardly to one face of the lar manner to that just described, and adjustably connected by a bar 21 and a set screw 22. By turning the latter, the casings may be moved toward or away from each other,.in the direction indicated by the arrows in Eig. 8, .to-properly locate the sight opening with respect to the eyes'of the operator, after which the set screws may be tightened to. hold the casing in proper position. In this construction, the reflectors 10 of eachcasing may be suitably connected bymeans of a rod 23 which has suitable connection therewith, in order to allow for the adjustment of the casings 1, and which rod 23 is in threaded engagement with an adjusting screw 24, whereby the adjustment of the said reflectors 10 is accomplished.
In Fig. 9 I have shown a form of prism which may be employed, if desired, wherein instead of mounting the lens 8 as shown in Fig. 1, independent of the prism or reflector, a lens 25- is carried thereupon and may be located upon either face of the prism, if desired, but in either case, the operation and effect will be substantially the same since the objective 8 may be positioned, so that the light will pass it before reaching the reflector 9 or after being reflected therefrom.
' From the foregoing description, it will be understood that when this instrument is used as an optometer or eye testing device,
' any adjustment of the reflector or light directing means 10 from normal position, as
at zero, will indicate an error in the refraction of the eye under examination, as well as its character, and the scale 14 and pointer 12 are employed for the purpose of mdicatin the nature and strength of the lens require for the correction of the existing refractive error in the eye under examination. The scale 14 isgraduated in ophthalmic lens or dioptric measurements, and willtherefore indicate any lens equivalent which may be necessary for the correction of errors of refraction in the eye under examination. It
will also be seen from the foregoing descrip- 1 1 til 'tli
insane? I tion that the instrument .is provided with an. objective lens and an-eye lens of substantially the same focal power, and that in consequence thereof, the object when viewed through the instrument will not be ainpliv and the cotiperationtherewith of the pointer and scale. It will also be seen that in this form of optometer neither the eye-piece nor the objective are necessarily adjusted for the purpose of determining the refraction of the eye under examination, and in addition to the image being erected, by reason of the novel construction of the instrument, a positive eye piece may be em loyed and a ergo and well illuminated" eld obtained thereby.
From the above, it will be understood that I have devised'a new and useful optical instrument embodying an objectiveflens and an alternate eye-piece, and a plurality of re-1 fiectors, with means for increasing or decreasing the focal range and the magnifying power of the instrument In the construction illustrated, I have mounted the objective lens and eye-piece in suitable relation to each other, and have provided means adapted to direct the light from one lens to the other in a manner which erects the image and gives an upright position to the object when viewed through the instru ment.
Having thus described my inventiomwhat I claim as new and desire to secure by Letters Patent, ,is:-
1. In an ophthalmological instrument, an objective lens, a reflector coiiperating therewith, an eye lens, a reflector eoiiperating therewith, a third reflector lcot'iperating with the first and second mentioned reflectors, means for increasing or decreasing the distance which the light will travel in passing from the objective lens to the eye lens, and means for indicating theincrease or decrease of light travel in ophthalmic lens values.
2. In an ophthalmological instrument, an objective lens, a reflector suitably positioned with respect thereto, an ocular lens of substantially the same focal power as said ob-' jective lens, a reflector suitably positioned with respect thereto, and a third reflector suitably positioned to reflect the light from the first-mentioned reflector to the secondmentioned reflector and movably mounted to increase or decrease the distance the light will travel in passing from the objective to theiocular lens, and means for indicating the" increase ordccrease of light travel in ophthalmic lens values.
3. In an ophthalmological instrument, the combination of an objective lens and an eye piece of substantially the same focalpower as said objective lens, whereby the object when viewed through the said lens and eyepiece will appear of substantially normal size, with reflecting means for erecting the image and for increasing and decreasing the distance which the light will travel in passing from the objective lens to the eye-piece,
and an indicating means coiiperating with a dioptric scale for indicating the nature of the light rays emanating from the eye-piece.
4. In an ophthalmological instrument, the combination with an objective lens having a positive focal point, and an eyepiece also having a positive focal point substantially the same as said objective lens, of reflecting means for erecting the image and for varying the distance of the'light travel between said objective and said eye-piece, and means for determining the amount of said variations in said distances in ophthalmic lens equivalents. 5. In an ophthalmologicalinstrument, a support, a reflecting device carried thereby for directing light to the object, an objective lens suitably supported with relation to said reflecting device, a reflector for said objective lens, a sight opening, a reflector for said sight opening, means for directing the light from one reflector to the other redoctor, said means being adjustable with respect thereto, an ophthalmic lens-scale for determining the amount of adjustment of the light directing means, and a series of lenses suitably mounted tovbe brought into alinement with said sight opening.
6. In an ophthalmoscope, a body portion, a source of light, a reflector adapted to direct light from said light source to the oba source of light, a reflector adapted to direct light from said light source to the object, a lens and a reflector enacting therewith, a second lens and a reflector coacting therewith, a third reflector for-directing the light from the first to the second mentioned reflector, and movable means carrying the third reflector for focusingthe instrument for the correction of errors in the refraction of the observed eye, said means indicating substantially the required corrective lens values.
8. In an ophthalmoscope, a body portion, I
a source of light, a reflector adapted to diltd rect light from said light source to the object, a lens and a reflector coacting therewith, 'a second lens and a reflector coacting therewith, a third reflector for directing the light from the first to the second mentioned reflector, means movably supported by the body portion and carrying the third reflector for focusing the instrument, and means for indicating the amount of the focusing adjustment in ophthalmic lens values.
9. In an optical instrument, a support, a reflecting device carried thereby for directing light to the object, a light opening, a
reflector for the light opening, an eye-piece, a reflector for said eye-piece, means for directing the light from one reflector to the other, said means being adjustable with respect thereto, an ophthalmic lens-scale for determining the amount of adjustment of the light directing means, and a seriesof lenses suitably mounted to be brought into visual alinement with the instrument.
HENRY L. DE ZENG.
Vitnesses:
M. GANER WIEDERSEIM, K. M. BROPHY.
US9903A 1915-01-11 1915-02-23 Ophthalmological instrument. Expired - Lifetime US1158187A (en)

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US156215A US1152152A (en) 1915-01-11 1915-01-11 Optical instrument.
US9903A US1158187A (en) 1915-01-11 1915-02-23 Ophthalmological instrument.

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2882789A (en) * 1953-08-18 1959-04-21 Mathew R Wilson Dual retinoscope
US5757460A (en) * 1996-09-16 1998-05-26 Cockley; Thomas D. Combination ophthalmic device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2882789A (en) * 1953-08-18 1959-04-21 Mathew R Wilson Dual retinoscope
US5757460A (en) * 1996-09-16 1998-05-26 Cockley; Thomas D. Combination ophthalmic device

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