Ophthalmologic examination and/or treatment apparatus including illuminator and magnifier assembly

Ophthalmologic apparatus includes a light source for obliquely directing light beams into an eye to be examined to illuminate a region of interest therein, a lens system for viewing the region of interest, an optical magnifier assembly for magnifying the viewed region of interest, and an image intensifier for intensifying the image of the viewed region of interest. The light source directs light into the eye from opposite sides thereof to intersect in the plane of the region of interest in the eye.

FIELD AND BACKGROUND OF THE INVENTION 
The present invention relates to ophthalmologic apparatus particularly 
useful for eye examination and/or for treatment of various eye disorders. 
Studies show that some of the leading causes of blindness are accompanied 
by pathologic development of the vascular net in the retina. One of these 
pathologies is a vascular net in the chorio-retinal complex. This net is 
supplied by only a few feeding vessels. Generally speaking, the 
presently-available ophthalmologic apparatus is capable of only regional 
examination and regional treatment, and is incapable of examination and/or 
treatment at the capillary level. As a result, the use of such apparatus 
does not enable detailed examination of the capillary blood vessels in the 
pathologic vascular net nor accurate location of the few vessels feeding 
the pathologic vascular net. These limitations limit the usefulness of the 
known apparatus for eye examination and/or treatment. 
OBJECTS AND BRIEF SUMMARY OF THE INVENTION 
An object of the present invention is to provide ophthalmologic apparatus 
having advantages in the above respects, particularly in enabling an 
accurate examination and/or treatment of the vascular net at the capillary 
(retinal and choroidal) level. 
According to the present invention, there is provided ophthalmologic 
apparatus comprising: illuminating means for directing light into an eye 
to be examined to illuminate a region of interest therein; a lens system 
for viewing the region of interest of the eye to be examined; an optical 
magnifier assembly for magnifying the viewed region of interest; and an 
image intensifier for intensifying the image of the viewed region of 
interest. 
According to one feature of the present invention, the illuminating means 
comprises an annular light source; and an annular reflector coaxial with 
the annular light source for reflecting the light into the eye from all 
sides thereof to intersect in the plane of the region of interest in the 
eye. 
According to another aspect of the present invention, the apparatus further 
includes an endoscope adapted to penetrate the eye for viewing a selected 
region thereof. 
Such an apparatus is useful when a fluorescent material is injected into 
the patient to enable viewing the blood flow in the eye. The provision of 
the image intensifier (which may be a known light amplifier) minimizes the 
intensity of the light required for illumination, thereby producing less 
light toxicity and less interference from scattered light. It also 
minimizes the amount of fluorescent material required to be injected, 
thereby not only saving on the cost of such material, but also minimizing 
leakage of the material to surrounding tissue and background noise, 
thereby producing better resolution. 
Apparatus constructed in accordance with the foregoing features enables the 
apparatus to view under magnification blood vessels at the capillary level 
and thereby to assess the condition of the eye, as well as other health 
conditions of the subject which may be indicated by the condition of the 
eye. The apparatus may also be used for treatment of the eye, at the 
capillary level, by means of a laser beam. 
Further features and advantages of the invention will be apparent from the 
description below.

DESCRIPTION OF PREFERRED EMBODIMENTS 
The apparatus illustrated in FIGS. 1 and 2 is a non-invasive type of 
apparatus for examining the eye with respect to various types of eye 
disorders, and also for treating the eye if necessary by means of a laser 
beam. The apparatus includes a housing, generally designated 2, comprising 
a main section 2a, a front section 2b, and two rear sections 2c and 2d. 
The housing 2 is mounted to any suitable support by a bracket 4 integrally 
formed with the front housing section 2b. 
The front housing section 2b includes an annular light source 6 coaxial 
with the optical axis OA of the apparatus and adapted to illuminate the 
eye (shown at E) to be examined or treated by the use of the apparatus. 
The annular light source 6 is in the form of a circular array of point 
light emitters, or LEDs (light emitting diodes), projecting light beams 
forwardly of the apparatus and parallel to its optical axis OA. The 
annular array of light beams are reflected by an annular lens 8 out 
through an opening 9 in the front end of the housing covered by a contact 
lens 10 which is brought into direct contact with the eye E being examined 
or treated. Annular lens 8 is a catadioptric or mirror lens having a first 
annular reflector surface 8a (FIG. 2) on its forward side and a second 
annular reflector surface 8b on its rear side for reflecting the light 
through the housing opening 9 obliquely to the optical axis OA and to the 
eye E being examined via the contact lens 10. 
It will thus be seen that in the arrangement illustrated in FIGS. 1 and 2, 
the light enters the eye from a plurality of sides of the eye obliquely to 
the optical axis OA of the apparatus and of the eye. The oblique angle of 
the light entering the eye is selected so that the light from a plurality 
of sources intersects in the plane of the region of interest in the eye, 
to thereby provide intense illumination of that region of interest. To 
permit preselecting the plane of intersection of the light beams, the 
annular lens 8 and contact lens 10 are mounted on a head 12 which is 
movable axially of the apparatus, towards or away from the eye, by a motor 
M. Motor M is carried by the head 12 and drives a pinion 14 which meshes 
with a gear hub 16 carried by the forward housing section 2b. The 
arrangement is such that rotation of pinion 14 moves head 12, and with it 
the annular lens 8 and contact lens 10 towards or away from the eye. 
The light reflected from the interior of the eye E passes through the 
contact lens 10, through a lens system 20 also carried by the front 
housing section 2b, and then through the main housing section 2a and the 
two rear housing sections 2c, 2d. The main housing section 2a includes a 
magnifier assembly, generally designated 22, in the form of a rotatable 
turret which may be rotated in order to select a desired magnification. 
The main housing section 2a further includes a beam-folding prism 24 for 
reducing the total length of the housing in order to focus the light 
emitted from the eye E at the rear end of the housing, i.e., at the end of 
the rear housing section 2d. 
Housing section 2c houses an image intensifier 26 which intensifies the 
image of the eye. The rearmost housing section 2d houses a lens system 28 
for focussing the light, and also a coupling collar 30 at the end of the 
housing section for attaching an eyepiece 32 to enable eye viewing the 
image. Coupling 30 may also be used for attaching thereto a video camera 
(as shown in FIG. 9), e.g., a CCD array, for displacing the eye image at 
another location, and/or for recording it. 
The front housing 2b further includes a connector 34 for attaching thereto 
a laser 36 adapted to project a laser beam into the eye E, e.g., for 
treating the eye. The laser attachment 34 aligns the laser 36 with an 
opening 38 in the front housing section 2b substantially perpendicular to 
the optical axis OA. A beam splitter 40 reflects the laser beam out 
through the front housing opening 9 into the eye E via the contact lens 
10. Beam splitter 40 also transmits therethrough the light reflected from 
the viewed region of the eye entering the housing via contact lens 10 to 
the opposite end of the housing occupied by eyepiece 32. 
Annular lens 8 also serves as a zoom lens to enable the size of the viewed 
region of interests of the eye to be rapidly changed. For this purpose the 
mirror lens 8 is mounted on a lens collar 42. Collar 42 is fixed to a zoom 
sleeve 44 (FIG. 2) by a pin 46 and meshes with the hub of a gear 48 which 
may be manually rotated driving a pinion 50 meshing with gear 48. Annular 
lens 8 may thus be moved in the axial direction, parallel to the optical 
axis OA, with respect to its annular light source 6. 
Contact lens 10 is floatingly mounted by a coiled spring assembly 52 to the 
front end of the front housing section 2b so that it may be brought into 
direct contact with the eye E being examined, without applying undue 
pressure to the eye. A pressure control unit 53 (FIG. 2) cooperable with 
spring assembly 52 provides accurate measurement of the pressure applied 
on the eye, and can be used for either controlling motor M and/or an 
indicator (not shown) to prevent excessive pressure from being applied to 
the eye, and/or for providing an indication if excessive pressure Should 
be applied to the eye. 
The distance between the contact lens 10 to the relay system 20 may be 
adjusted by means of a threaded fastener 56 (FIG. 2) to compensate for 
variations in the RPE (retinal pigment epithelium) location 54 which 
varies with the eye size. 
The manner of using the apparatus illustrated in FIGS. 1 and 2 will be 
apparent from the above description. Thus, the apparatus is positioned to 
bring the contact lens 10 into direct contact with the subject's eye E, 
while the coiled spring 52 carrying the contact lens, and the pressure 
sensor 53, prevent undue pressure on the eye. Compensation for variations 
in the location of the RPE 54 because of the eye size may be made by the 
use of threaded fastener 56. 
The interior of the eye is illuminated by the annular series of light 
sources 6 projecting the light through the annular lens 8 within the 
housing 2 into the eye E via the contact lens 10. As described earlier, 
the light entering the eye obliquely from many sides is preset to 
intersect in the plane of the region of interest in the eye. Such an 
arrangement provides relative intense illumination at the region of 
interest, and at the same time minimizes interference with the light 
reflected from the eye and to be observed during the examination. 
The light reflected from the eye E is passed through the relay lens 20 and 
the magnifier assembly 22, the beam folding prism 24, the image 
intensifier 26 and the lens system 28, and may be viewed through the 
eyepiece 32 (or a video camera) at the opposite end of the apparatus. 
Magnifier assembly turret 22 may be rotated to select any desired 
magnification, e.g., from 20.times. to about 250.times.. If the size of 
the viewed region of interest of the eye is to be changed, gear 48 may be 
manually rotated to move the lens collar 42 of the annular mirror lens 8 
forwardly or rearwardly with respect to the contact lens 10. 
If the eye is also to be treated by a laser beam, laser 36 is attached via 
the attachment 34 to project its laser beam through opening 38 into the 
interior of the housing. Beam splitter 40 reflects the laser beam along 
the optical axis OA into the subject's eye E via the contact lens 10. The 
light emitted from the eye E passes through the relay lens 20, beam 
splitter 40, magnifier assembly 22, beam folding prism 24, image 
intensifier 26, and eyepiece 32 at the opposite end of the apparatus. If 
it is desired to transmit the image of the eye to another location or to 
record it, this can be done by replacing the eyepiece 32 with a video 
camera unit, such as a CCD a shown in FIG. 9. 
FIG. 3 illustrates an implementation of the invention in another type of 
ophthalmologic apparatus for examining and/or treating an eye disorder. 
The apparatus illustrated in FIG. 3 includes a housing 102, of similar 
construction as in FIGS. 1 and 2, enclosing a turret-type magnifier 
assembly 122, a beam folding prism 124, and an image intensifier 126. 
Housing 102 in FIG. 3 also includes an attachment 134 for attaching a 
laser to project a laser beam to a beam splitter 140 which reflects the 
laser beam along the optical axis OA of the apparatus into the eye being 
examined, and passes the image reflected from the eye through the relay 
lens assembly 120, magnifier assembly 122, beam folding prism 124, and 
image intensifier 126 to the eyepiece 132 at the opposite end of the 
apparatus. 
However, the apparatus of FIG. 3 does not include a contact lens, 
corresponding to contact lens 10 at the front part of the apparatus for 
contact with the eye being examined; rather, it includes an endoscope 150 
adapted to penetrate the eye, as shown in FIG. 4. As further shown in FIG. 
4, the interior of the eye is illuminated by a separate illuminator, 
generally designated 160, which is placed into contact with the eye, and 
not by an illuminator within the housing 102, as in the FIGS. 1 and 2 
apparatus. 
The endoscope 150 may contain an irrigation/aspiration port 152, and fiber 
optics for illumination. In that case, the illuminator 160 is not needed. 
Since the space in the endoscope is limited, using part of it for 
illuminating fibers would be on the account of the image quality achieved 
by the system. 
Illuminator 160, for illuminating the eye being examined and/or treated, is 
illustrated in FIGS. 4-7. This illuminator is also of annular shape. It 
includes an annular-shaped lens 162, and an annular array of light sources 
164 supported around the outer periphery of the annular lens 162 and 
oriented such that the lens reflects the lens from the light sources into 
the eye. For this purpose, the annular lens 162 includes an annular 
reflector surface 162a (FIG. 7) on the front face of the lens in contact 
with the eye, and an annular reflector surface 162b on its rear face, such 
that the light is directed by the two reflector surfaces inwardly of the 
eye along an annular array of converging paths as illustrated by arrows 
166 in FIGS. 5 and 7, while the eye is observed via the window 168 in the 
illuminator as indicated by arrow 169 in FIG. 7. 
As shown particularly in FIG. 4, the light enters the eye obliquely from a 
plurality of sides and intersects at the plane of the region of interest 
in the eye. As described above with respect to the FIGS. 1 and 2 
embodiment, such an illumination system maximizes the intensity of 
illumination of the region of interest and also minimizes the interference 
with the light reflected back out of the eye to enable viewing the region 
of interest. 
The annular array of light sources 164 may be point light emitters, such as 
LEDs, optical fibers, or the like. Each light source 164 is pivotally 
mounted by a pin 171 to a pair of posts 172 formed on a ring 174 extending 
around the periphery of the annular lens 162, to vary the angle of the 
light sources with respect to the optical axis of the illuminator, and of 
the eye, in order to change the plane of the point of intersection of 
their light beams within the eye. For this purpose, each light source 164 
is formed with an ear 176 at its upper end adapted to receive a common 
adjusting ring 178 of variable diameter, such that increasing the diameter 
of adjusting ring 178 pivots all the light sources 164 simultaneously in 
one direction, and decreasing the diameter of ring 170 pivots the light 
sources simultaneously in the opposite direction. 
Annular illuminator 160 is provided with a knob 180 (FIG. 5) which may be 
manually rotated in order to increase or decrease the diameter of 
adjusting ring 178. This is more particularly illustrated in FIGS. 5 and 
8, wherein it will be seen that the two ends of adjusting ring 178 are 
formed with teeth, as shown at 178a, 178b, engageable with a toothed wheel 
182 fixed to knob 180, such that rotation of the knob in one direction 
draws the ends 178a, 178b of the adjusting ring together to decrease its 
diameter, whereas rotating the knob in the opposite direction moves the 
two ends apart to increase the diameter. 
When using the apparatus illustrated in FIG. 3, the annular illuminator 160 
illustrated in FIGS. 5-7 is placed over and in direct contact with the 
eye. The variable-diameter ring 178 is then adjusted by rotating knob 180 
to pivot all the point light sources 164 such as to illuminate the region 
of interest of the eye, as illustrated in FIG. 4. The endoscope 150 (FIG. 
3) is then inserted into the eye in alignment with the region of interest. 
While the interior of the eye is illuminated by the annular illuminator 
160, the region of interest may be viewed via the endoscope 150, relay 
lens system 120, magnifier assembly 122, beam-folding prism 124, image 
intensifier 126, and the eyepiece 132 (or video camera if used), in the 
same manner as described above with respect to FIGS. 1 and 2. The area of 
interest in the eye may also be viewed directly, or by a microscope, 
through the central window 168 in the annular illuminator 160. If the 
interior of the eye is also to be treated by a laser beam, the laser is 
energized and its beam is directed by beam splitter 140 via the endoscope 
150 into the eye, in substantially the same manner as described above with 
respect to FIGS. 1 and 2, except in this case that the laser (not shown) 
is mounted to pass its beam through the endoscope 150 rather than through 
the contact lens 10. 
FIG. 9 illustrates a variation wherein the coupling collar 30 in FIGS. 1 
and 2 is used for coupling thereto both an eyepiece 200 and a video camera 
202, e.g., a CCD camera, to enable the area of interest of the eye being 
inspected also to be viewed from a remote location and/or to be recorded. 
It will be appreciated that the video camera attachment illustrated in 
FIG. 9 could also be applied to the apparatus illustrated in FIG. 3. 
FIG. 9 also illustrates another method of illumination using an external 
light source, in this case an optical fiber 204 leading to a light source 
205. The optical system in this case includes a barrier filter 206, a 
condensing lens system 208, and an annular mask 209 having a circular 
array of openings 210, which produces an annular array of light beams. 
These light beams are reflected from a beam splitter 210 within the 
housing onto the eye being examined so as to enter the eye also obliquely 
from a plurality of sides, and thereby to intersect at the plane of 
interest within the eye, as described above with respect to the 
embodiments of FIGS. 1, 2 and 3-8. 
In all other respects, the apparatus illustrated in FIG. 9 is similar to 
that described above particularly with respect to FIGS. 1 and 2.