WO1997036537A1

WO1997036537A1 - A camera adapter for an eye examination device

Info

Publication number: WO1997036537A1
Application number: PCT/US1997/000692
Authority: WO
Inventors: J. Curtis Creed
Original assignee: Creed J Curtis
Priority date: 1996-03-29
Filing date: 1997-01-22
Publication date: 1997-10-09

Abstract

The present invention provides a device including an adapter that converts pre-existing eye examination units, such as converging optics slit lamps, into visual recording eye examination units. One embodiment of the adapter comprises a body with a front and rear aperture. The front aperture (68) is formed to matingly receive an eye piece (5) of an eye examination unit and the rear aperture (71) is formed to receive a camera lens (70). An alternate embodiment of the adapter comprises a clamp member (12) and a camera frame member (38) pivotally connected to said clamp member (12) with a spacer and filter element (21) positioned between the clamp member (12) and frame member (38). Another embodiment of the adapter comprises a viewing tube (50) connected to a head portion (51) and having a first line of sight. A prism (53) positioned in the head portion directs said first line of sight to a second line of sight.

Description

A CAMERA ADAPTER FOR AN EYE EXAMINATION DEVICE

TECHNICAL FIELD

The present invention relates to ophthalmological devices and in particular devices for

photographing or video taping the eye as viewed through standard examining equipment, such

as a conventional ophthalmic slit-lamp or bio-microscope Furthermore, the present invention has unique application to the area of ocular angiography

BACKGROUND ART

The prior art contains numerous devices designed specifically for photographing and/or

video taping various parts ofa human eye undergoing examination These devices generally consist ofa senes of lenses producing the properly magnified and focused image of the eye and a camera device or video device to record this image A platform mounted version of such a device can be seen in U.S Patent 3,915,564 to Urban and a more modern, portable device can be seen in U S Patent 5,125,730 to Taylor, et al

While not the only use for devices as described above, some of these devices may also

be beneficial in the area of angiography Angiography generally consists of introducing a light excitable dye into the blood supply circulating through the eye As the dye carrying blood

flows through blood vessels in the eye, the eye is illuminated with a wavelength of light which excites the dye and causes the dye to emit light itself An "exciter filter" will be placed

between the light source and the eye which will filter out all wavelengths of light except the wavelength which excites the dye A second filter or "barπer filter" will be positioned between the eye and the observer The barrier filter will filter out all wavelengths of light except those emitted by the dye The angiography procedure will typically be fluorescein angiography, but

may also be indocyanine green (or ICG) angiography When employing fluorescein angiography, the exciter filter will be blue-green and the barrier filter will be yellow. When employing ICG angiography, the exciter filter and the barrier filter will be infra-red.

The angiography process allows the eye examiner to obtain a detailed image of the blood circulatory conditions in the eye. The image produced through fluorescein or ICG angiography is generally recorded by photographic or videographic devices such as described in the above mentioned patents.

However, while some prior art devices can perform angiography and other procedures, they also have numerous disadvantages. These devices typically require specialized training of the medical personnel using the camera rather than allowing personnel to use skills already developed for existing devices such as slit-lamps. The prior art devices typically use film that must be developed. This requires the eye care practitioner to have his own dark room or experience considerable delays by sending film to an out-of-house developing lab. Even with a dark room, it may be several hours (long after the patient has departed) before the results of the exam can be reviewed. Nor are the prior art devices typically portable, but rather because

of their size, are difficult to conveniently move to different locations. Although the above cited

Taylor patent discloses a portable device, it is still comparatively large and expensive. Also, because these devices employ both high grade optics and complex photographic or videographic equipment, they are necessarily expensive to produce. In view of these disadvantages, many eye care practitioners are forced to refer a patient to a specialist in this field, entailing more delays and expense for the patient. Often, the ophthalmologist or optometrist has need of such a specialized device for performing videographic or angiographic

procedures, but the considerable capital investment is prohibitive.

What is needed and what would be a great advance in the art is a device that would allow widely existing optical examining devices, such as converging optics slit lamps, to be adapted for photographic, videographic or angiographic recording. Converging optics slit lamps are one of the most common examination devices used by eye care practitioners. None of the prior art devices allow conversion of the pre-existing optics on a converging optics slit lamp into a videographic device for angiographic or other applications.

The present invention is not only a device capable of adapting converging optics slit

lamps to photographic, videographic or angiographic recording units, but also has numerous

additional advantages. The present invention is easily portable and may be moved to different locations or just as easily to different slit-lamps located in the same office building.

Additionally, the present invention can quickly be positioned on the slit-lamp when

videographic or angiographic recording is required and then quickly removed when the procedure is finished. This ease of transformation means that a slit-lamp does not have to be dedicated to only videographic use, but may also be quickly converted back to its traditional operation. Furthermore, by providing a method of interfacing a video camera with an existing slit-lamp, the present invention provides instantaneous, real time images of the eye being

examined. There are no delays or expenses associated with developing or dark rooms. Also,

because the image of the eye is reproducible on a video screen in the examination room, the

patient can immediately be shown the results of the eye examination. The patient does not have to come back at a later date. The present invention also provides high resolution imaging of not only the internal parts of the eye, but all aspects of ocular anatomy, such as the eye lids

and surrounding area. Finally, the present invention allows the eye care practitioner and his or her staff to employ their existing skills for using the conventional slit-lamp rather than having to master a whole new procedure such as found in prior art devices. It is clear that the present invention would render visual recording of eye examinations much more economical and therefore much more predominant, thereby greatly increasing the quality of care eye practitioners can offer their patients.

DISCLOSURE OF THE INVENTION

It is an object of this invention to provide a device which converts pre-existing eye

examination units such as converging optics slit lamps into visual recording eye examining

units that may be used for videographic and angiographic examination.

It is another object of this invention that the device be highly portable and that the device can be quickly attached to and removed from pre-existing eye examination units.

It is still a fiirther object of this invention that the device be able to provide instantaneous, real time, high resolution imaging of all aspects of ocular anatomy.

It is an object of this invention to provide a visual recording eye examining unit which

is far more economical than hereto known in the art.

Therefore, a device that converts pre-existing eye examination units such as converging

optics slit lamps into visual recording eye examining units is provided. The device generally comprises an adapter member attachable to the viewing element ofa slit-lamp and a camera

attached to said adapter member.

One embodiment of the adapter comprises a body with a front and rear aperture. The

front aperture is formed to matingly receive an eye piece ofan eye examining unit and the rear aperture is formed to receive a camera lens. An alternate embodiment of the adapter comprises a clamp member and a camera frame

member pivotally connected to said clamp member with a spacer and filter element positioned

between the clamp member and frame member. Another embodiment of the adapter comprises a viewing tube connected to a head

portion and having a first line of sight. A prism positioned in the head portion directs said first

line of sight to a second line of sight.

DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view ofa conventional slit lamp examination unit.

Figure 2 is an exploded view ofa preferred embodiment of the invention. Figure 2(a) is an illustration of how the embodiment ofFigure 2 may be rotated with

respect to the slit lamp.

Figure 3 is a side view and a partial cut-away view ofa second preferred embodiment of the invention.

Figure 4 is a schematic view of the second preferred embodiment of the invention, illustrating lenses and a penta prism.

Figure 5 is an cross sectional view of a third preferred embodiment of the present

invention.

Figure 6 is perspective view of the third preferred embodiment of the present invention.

Figure 7 is a side view and partial cut-away view ofa fourth preferred embodiment of the present invention.

Figure 8 is a cross sectional view of a fifth preferred embodiment of the present

invention.

Figure 9 is a perspective view of the exciter filter use in the present invention.

Figure 10 is a perspective view of a sixth preferred embodiment of the present invention.

Figure 11 is a front view of a sixth preferred embodiment of the present invention. Figure 12 is a side sectional view of a sixth preferred embodiment of the present invention.

Figure 13 is an exploded perspective view ofa seventh preferred embodiment of the present invention.

Figure 14 is a sectional side view of the adapter shown in Figure 15.

Figure 15 is an exploded perspective view ofan alternate embodiment of the adapter shown in Figure 13.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention provides an apparatus for converting a conventional eye examination unit 1 as seen in FIG. 1, into a novel and advantageous method of photographing

or video taping an eye under examination. A typical eye examination unit 1 which will be used

with the present invention is a slit lamp 2 similar to the apparatus shown in Fig. 1. However,

it is intended that the invention be employable with all eye examination devices having a

viewing element 3 which includes an eye piece 5 through which the examiner views the eye of

the patient. Besides slit lamp 2 seen in FIG. 1, such eye examination devices may include

operating microscopes, caratometers, or bio-microscopes.

In general, the invention (one embodiment of which is shown in FIG. 1 as 75) will

adapt a camera 7 for use with the eye examination unit 1. The term "camera" as used herein is intended to include all visual recording devices, including photographic cameras or still cameras, conventional video cameras, micro-video cameras, and digital cameras (such as

"CCD" cameras, "frame grabbers" or "computer cameras"). The use of digital cameras will

allow the invention to interface with existing software programs that aid in the examination of

the eye and the diagnosis of eye disorders. At present, the only way to interface with such software is to acquire very specialized and expensive videographic equipment specifically designed for this purpose.

It will be understood that since the term "camera" is being used in its broadest sense,

the invention is also intended to include whatever type oflcamera mount is needed to interface the camera with the rest of the invention. While specific embodiments may discuss "C-mount" or "CS-mount", those embodiments could comprise whatever camera mount is necessary to utilize the camera of interest.

Slit lamp 2 seen in FIG. 1 includes a light source 87 providing light which is reflected

off of mirror 88 into the eye of the patient. A viewing element 3 such as binocular unit 8,

allows the eye examiner to magnify and view sections of the eye in great detail. Binocular unit

8 includes an eye piece 5 positioned in eye piece receptacle 10. As shown in Fig. 1, eye piece

5 is removable from eye piece receptacle 10. Camera adapter 75 does not form part of

conventional slit lamp 2, but rather is part of the present invention which will be explained in

greater detail later in this specification. FIG. 2 illustrates a preferred embodiment of the present invention. Camera adapter

12 generally comprises a clamp member 14, a spacer element 21, and a camera frame member

38 which will be pivotally connected to spacer element 21 by way of pivot pin 23. Clamp

member 14 will have clamp aperture 15 which is sized to slide over the outer diameter of eye

piece receptacle 10. Rather than clamp member 14 forming a closed ring around clamp

aperture 15, clamp member 14 has two flanges 16 which provide a means for slightly opening and closing clamp aperture 15. In this manner, tightening screw 17 can be loosened to allow

clamp member 14 to slide over eye piece receptacle 10 and then tightening screw 17 can be

tightened such that clamp member 14 firmly grasps eye piece receptacle 10. Also positioned on clamp member 14 is threaded mounting aperture 18. Mounting aperture 18 will allow a small, typically 3 inch, liquid crystal display (LCD) screen (not shown) to be mounted on clamp member 14. When this embodiment is used with a video or digital camera 7, the LCD screen will allow the eye examiner to see what is being recorded by the camera 7. If the position of the patient's eye or the slit lamp 2 needs to be adjusted, the eye examiner has a ready visual reference by which to do so.

Spacer element 21 is generally of the same shape as clamp member 14 and will be

positioned against clamp member 14. Spacer element 21 will also have pinning aperture 22 for receiving pivot pin 23. Pivot pin 23 will engage frame member 38 as mentioned above and explained in greater detail below. Spacer element 21 includes spacer aperture 24 which will be positioned substantially in line with clamp aperture 15. Spacer aperture 24 is designed to

allow eye piece 5 to engage spacer element 21 while maintaining a clear line of sight through

spacer element 21. Spacer aperture 24 will be sized such that eye piece ring 6 will fit into spacer aperture 24 and rest securely in spacer element 21, eye piece ring 6 will be prevented from moving farther rearward by filter channel 30 (whose function is explained below).

Those skilled in the art will recognize that the combined thickness of spacer element

21 and clamp member 14 will be equivalent to the distance "a" that the eye piece 5 normally

extends from eye piece receptacle 10. In this manner, the eye piece 5 used in conjunction with

the invention will have the same focal distance as when the eye piece 5 is positioned directly in the eye piece receptacle 10 in the conventional manner as illustrated by eye piece 5 that has

not been removed in FIG. 2.

A filter element 28 will be removably positioned within camera adapter 12. Filter

element 28 will most typically be used in conjunction with angiography procedures such as previously described. In the embodiment shown in FIG. 2, filter element 28 comprises a filter

slide 31 having two filter lenses 32, with each filter lens 32 being ofa different color. Filter

lenses 32 will function as barrier lenses with one filter lens being yellow for fluorescein

angiography and one lens being black for ICG angiography. Filter slide 31 will slidingly

engage channel 30 which is formed in spacer element 21 and thereby allow filter lenses 32 to

be selectively inteφosed between camera lens 44 and eye piece 5. It will be understood that

while 2 filter lenses are shown, a single filter lens could also be employed in filter slide 31.

Additionally, while this embodiment of the invention discloses filter lenses 32 between camera

lens 44 and eye piece 5, it will be understood that filter lenses 32 could be positioned anywhere

between the patient's eye and camera 7 and still carry out its intended function.

A central bore hole 35 will be formed through clamp member 14 and continue into

spacer element 21, but not through spacer element 21. Central bore hole 35 in spacer element

21 will be threaded in order to engage screw 36 which passes through clamp member 14 and

terminates in spacer element 21. It will be seen from FIG. 2 that screw 36 holds clamp

member 14 and spacer element 21 securely together as a unit. When clamp member 14 and

spacer element 21 are secured with screw 36, eye piece 5 will be capable of being inserted

through aperture 15 with friction between eye piece ring 6 and the inner diameter of spacer

aperture 24 being sufficient to hold eye piece 5 in place. A plurality of pin holes 34 will also

pass through clamp member 14 and partially penetrate spacer element 21. Stabilizer pins 33

will be positioned in pin holes 34 to insure that there is no rotation between clamp member 14

and spacer element 21.

A frame member 38 will form the rearmost portion of camera adapter 12. Frame

member 38 includes a shell portion 39 which is sized to fit against clamp member 14 and enclose spacer element 21 and filter element 28. Frame member 38 will also have a plurality

of camera extension legs 40 which position camera ring 43 a fixed distance from shell portion 39. Extension legs 40 will have threaded ends 41 engaging shell portion 39 and screw driver

heads 42 on the opposite ends. A camera lens 44 will be positioned between shell portion 39

and camera ring 43 and a camera 7 will engage camera lens 44 such that camera 7 is securely

fixed to camera adapter 12. In the embodiment shown, camera ring 43 will have internal threads 47 to engage camera lens 44. Camera lens 44 will protrude somewhat beyond camera ring 43 such that camera 7 may be attached thereto. Typically, camera 7 will have a conventional "C-mount" or "CS-mount" for engaging camera lens 44. However, it is envisioned that the invention could be adapted for used with any type of camera mount.

Frame member 38 will also be pivotally connected to spacer element 21 by way of pivot pin 23 engaging pivot hole 45 such that frame member 38 may swing to the side in a 180° arc on spacer element 21. Frame member 38 will have bridge portion 46 which strengthens

frame member 38, but still allows frame member 38 to pivot without being obstructed by filter

element 28. As illustrated in FIG. 2(a), this configuration allows the frame member 38 (with

camera 7 attached thereto) to be easily pivoted to the side so that the eye examiner may look though spacer aperture 24 in spacer element 21 (when filter slide 31 is not inserted into filter element 28) and see directly into eye piece 5.

Those skilled in the art will understand the significant advantages of the present

invention when combined with conventional slit lamps 2. When an examiner desires to use slit lamp 2 in the conventional manner, frame member 38 may be pivoted to the side and the eye examiner views the eye through eye pieces 5 as in the typical examination. If the eye examiner

desires to record what he is viewing, he may simply pivot the frame member 38 (and thus camera 7) against clamp member 14. In this manner, shell portion 39 encloses spacer element

21 such that camera lens 44 is next to spacer element 21. Thus camera 7 is in line with eye

piece 5 and in a position to begin recording.

Additionally, when the camera 7 is pivoted away from clamp member 14, camera 7 can

be used for recording areas other than internal sections of the eye. For example, the entire slit

lamp apparatus 2 could be pivoted such that camera 7 could focus on the patient's face without

viewing through eye piece 5. This allows the eye examiner to record the external features of

the patient's eyes such as the condition of the eye lids and areas surrounding the eye. These

advantages are in addition to the angiography applications to which the present invention is

well suited. Those skilled in the art will appreciate the present invention, when employing filter lenses 32, allows a conventional slit lamp found in virtually every eye care facility to be cheaply and quickly converted into an angiography examination device.

An second embodiment of the invention is seen in FIG. 3. In this embodiment, camera

adapter 49 comprises a viewing tube 50, the outer diameter of which is sized to engage the

inner diameter ofan eye piece receptacle 10 (such as seen in FIG. 1), a head portion 51, and

a neck portion 52. While FIG. 1 illustrates an alternate adapter embodiment which is

discussed below, it will be understood that the present embodiment of FIG. 3 engages viewing

tube 50 with eye piece receptacle 10 in the same manner as shown in FIG. 1. The lens 61 in

viewing tube 50 will be positioned such that the image being viewed (a patients eye) will be

focused on a prism 53 inside of head portion 51.

Head portion 51 is a hollow structure in which prism 53 will be positioned. As best

seen schematically in FIG. 4, prism 53 is a penta prism which will serve to redirect a first line

of sight 54 parallel to viewing tube 50 to a second line of sight 55 running parallel to neck portion 52. Light will enter viewing tube 50 along first line of sight 54 and pass through front

face 64a of prism 53. Light will then be reflected off of rear face 64b to top face 64c of prism

53 and then exit through lower face 64d. These multiple reflections inside of prism 53 will

serve to avoid a right-left inversion or the production ofa mirror image as viewed from second

line of sight 55.

As the image being viewed is directed along the second line of sight 55, it passes

through a filter element 57, an iris 60, and two additional lenses 62 and 63 which are

positioned in neck portion 52. The lens arrangement in neck portion 52 insures that the image

will be properly focused on a camera 7 which will be positioned at the bottom of neck portion 52 (see FIG. 3). The spacing of the lenses in this embodiment can be seen in FIG. 4. Lens

61 will be a lens such as Edmond Scientific E32963 20D 60F. Lens 61 will be a distance b

from prism 53, which will be a prism such as Edmond Scientific E31051 20 FACE. Lens 62

will be a lens such as Edmond Scientific E32915 18D 80F and will be positioned a distance c

from prism 53. Lens 63 will be a lens such as Edmond Scientific E32913 18D 50F and will

be positioned a distance d from lens 62. In the embodiment shown if FIG. 4, b is equal to

23mm, c is equal to 52mm and d is equal to 28mm. While this embodiment has been described

in terms of specific lenses spaced at specific distances, those skilled in the art of optics will

understand that many different lenses can be used and the spacing will vary according to the

lens used. The spacing will vary to insure that the lens of camera 7 is the proper focal point

of second line of sight 55.

As previously mentioned, the camera adapter 49 shown in FIG. 3 will have a filter

element. Filter element 57 is illustrated as having black lens 58a for ICG angiography, yellow

lens 58b for fluorescein angiography, and clear lens 58c for non-angiographic viewing. Filter element 57 will slidingly engage neck portion 52 such that the lenses 58 can selectively be

moved into the line of sight 55.

To provided a convenient means for attaching and detaching camera 7, a conventional

CS-mount 59 will be positioned on the bottom of neck portion 52. An iris 60 and filter

element 57 are also positioned in neck portion 52. Iris 60 will regulate the amount of light

being received by camera 7 depending on the application in which the invention is being used. As with the previous embodiment, the function of filter element 57 in conjunction with angiography procedures is a great advantage over the prior art.

A third embodiment can be seen in FIG. 5. In this embodiment, camera adapter 66

comprises a body member 67 with front aperture 68 and rear aperture 71. Front aperture 68

is formed with shoulders 69 such that it may matingly receive conventional eye piece ring 6

such that eye piece 5 is held firmly in place in body member 67. It will be understood that the

embodiment of FIG. 5 is similar to that of FIG. 2 in that both embodiments employ the eye

piece 5 from a conventional eye examination unit. Rear aperture 71 is sized such that it may

receive a conventional camera lens 70. However, it is intended that rear aperture 71 could be

sized to accommodate any type of lens and camera combination. As best seen in FIG. 6,

adapter 66 will have a broken section 72 and tightening screw 73. This will allow adapter 66

to securely engage camera lens 70 and eye piece 5. Adapter 66 will also have a mounting

aperture 74 for receiving a small LCD screen as described in the first embodiment. When

adapter 66, eye piece 5 and camera 7 are joined as a unit as seen in FIG. 6, eye piece 5 may

be inserted into an eye piece receptacle and video recording of the eye examination may

proceed. While not shown in the figures, adapter 66 could also include a slidable filter

element. Such a filter element could be constructed similar to filter element 28 shown in FIG. 2. If the rear of adapter 66 is extended, a slot for the sliding filter element could be formed

therein such that the filter element would be positioned between eye piece ring 6 and lens 70.

This arrangement would allow adapter 66 to be used in angiography procedures.

A fourth embodiment ofan adapter member 75 can be seen in Fig. 7. As in the second embodiment seen in FIG. 3, the fourth embodiment illustrated in FIG. 7 has a viewing tube

76 attached to a head portion 77 and a prism 80 positioned inside of head portion 77. Viewing

tube 76 is substantially the same as viewing tube 50 disclosed in FIG. 3. However, prism 80 does not perform the same function as prism 53 disclosed in FIG. 3. Prism 80 is a beam

splitting prism that simultaneously directs the line of sight from viewing tube 76 in two

different directions. Beam splitting prism 80 directs a first line of sight 78 toward fixed eye piece 81 which is attached to the rear of head portion 77. Through fixed eye piece 81, the eye examiner is able to directly view the eye under examination. Simultaneously, beam splitting prism 80 directs a second line of sight 79 in the direction of camera 7. In this manner, the

invention allows the examiner to directly view the eye at the same time camera 7 records what

the examiner is viewing. Neck portion 82 will contain lenses spaced at intervals necessary to have second line of sight 79 focus on camera 7. Iris 83 will also be positioned on neck portion

82 in order to regulate the amount of light being received by camera 7.

A fifth embodiment of the invention, camera adapter 95, can be seen in FIG. 8.

Camera adapter 95 generally comprises viewing tube 96 and adapter body 100. Viewing tube

96 is again substantially the same viewing tube as disclosed in the embodiments of FIGS. 3 and

7. Adapter body 100 further comprises front section 102, mid-section 103, iris section 104, and rear section 105. Front section 102 will be threadedly connected to viewing tube 96 and mid-section 103. Mid-section 103 will also be connected to iris section 104, which will contain iris 101 which will adjust the amount of light reaching camera 7 as in the previously described

embodiments. Iris section 104 will engage rear section 105 which will have threads 106 for

attachment to conventional camera mount.

Front section 102 and rear section 105 will contain lenses 97 and 98 respectively. As

those skilled in the art will appreciate, lenses 97 and 98 may be any number of conventional

lenses whose spacing may vary depending on the particular lenses used. In the embodiment

shown, lenses 97 and 98 are 33 diopter achromatic and 37 diopter achromatic lenses

respectively. The present invention is not considered limited to any particular type or number

of lenses, the only requirement being that the lens arrangement focus the image viewed on the lens of camera 7.

A sixth embodiment of the present invention is illustrated in FIGS. 10-12. FIG. 10 shows an adapter member 110 which generally comprises a body member 111, a rear plate

120, a camera sleeve 121 and a filter slide 119. Camera 124 is shown in phantom just prior

to its insertion to camera sleeve 121. While the camera shown in FIG. 10 is a 17mm diameter,

V2" CCD micro-camera, numerous alternated camera's could be used with camera sleeve 121

being sized accordingly.

Body member 111 in turn further comprises a clamp ring 115, a block 113, a pair of

flanges 116 (only one of which is visible in FIG. 10), and a forward plate 112. As best seen

in FIG. 12, clamp ring 115 will be formed integrally with block 113 and flanges 116. A

tightening screw 117 will engage flanges 116 allowing clamp ring 115 to close on an eye piece

receptacle 10 (see FIG. 1 illustrating an eye piece receptacle 10).

FIG. 11 is a cross-sectional view of the present embodiment illustrating the manner in

which the camera adapter 110 will be mounted on eye piece receptacle 10. In FIG. 11, the eye piece receptacle 10, eye piece 5, and camera 124 are all shown in phantom. The sectional view

of FIG. 11 also illustrates how clamp ring 115 is not attached to forward plate 112 along the

entire length of forward plate 112. Rather clamp ring 115 is only attached to forward plate

112 along the upper portion of clamp ring 115. The lower portion of ring clamp 115 and

flanges 116 are not connected to forward plate 112. This configuration allows clamp ring 115

to collapse slightly and securely grip eye piece receptacle 10 as flanges 116 are brought together.

Viewing FIGS. 10 and 11, it can be seen that filter channel 118 is formed in block 114

and forward plate 112. Filter channel 118 is sized to allow filter slide 119 to be removably

positioned in filter channel 118. When filter slide 119 is positioned in filter channel 118, the

filter lens will be interposed between camera 124 and eye piece 5. As discussed above, filter

slide 119 will allow camera adapter 110 to be used in conjunction with fluorescein and ICG

angiography procedures.

As best seen in FIG. 10, rear plate 120 will be attached to forward plate 112 by screws 123. Also, a set screw 122 will engage camera sleeve 121 in order to securely hold camera

124 in place when camera 124 is inserted into camera sleeve 121. Block 113 will have a

threaded aperture 114 to accommodate various camera accessories, such as a "hot-shoe". In

a preferred embodiment, camera adapter 110 will be constructed of a light weight flexible

metal such as conventional "aircraft" aluminum. However, it is envisioned that camera adapter

110 could be constructed of a wide range of suitable materials.

A seventh embodiment of the present invention is illustrated in FIGS. 13-15. FIG. 13

shows an adapter member 130 which generally comprises a body member 132, a rear plate

134, a camera sleeve 135 and a filter slide 137. Camera 7 is shown just prior to its insertion to camera sleeve 135. While the camera shown in FIG. 13 is a 17mm diameter, V% CCD micro-camera, numerous alternated cameras could be used with an alternative camera sleeve 135 being sized accordingly or with an alternative camera mounting systems as described

below in conjunction with the description of FIG. 15.

Body member 132 in turn further comprises a back wall 136 in which a filter channel

138 is formed. Back wall 136 also contains aperture 144 which forms a line of sigh between

eye piece 143 and camera 7. Body member 132 further comprises an adjusting slot 133 which

will accommodate a tightening screw 141, while the tightening screw 141 will engage an eye

piece retaining member 140. As seen in FIG. 13, retaining member 140 is a ring shaped body

having a center aperture 142 which is sized to receive conventional slit lamp eye piece 143.

The cross sectional view of FIG. 14 best illustrates how retaining member 140 will securely

hold eye piece 143 against back wall 136. Returning to FIG. 13, it will be seen that when

tightening screw 141 is loosely threaded into retaining member 140, retaining member 140

(with eye piece 143 extending through aperture 142) may be positioned inside of body member

132 with tightening screw 141 engaging adjusting slot 133. When eye piece 143 is positioned

between back wall 136 and retaining member 140, tightening screw 141 is tightened against

adjusting slot 133 to securely maintain eye piece 143 inside body member 132. It can be seen

that adjusting slot 133 allows retaining member 140 to move forward or backward as needed

to accommodate eye piece rings 131 of various sizes such as shown on eye pieces 143a and

143b.

The embodiment of adapter 130 shown in FIG. 13 will also comprises a rear plate 134. Rear plate 134 will include camera sleeve 135 extending from rear plate 134 and camera sleeve

135 will have an internal passage sized to review camera 7. Rear plate 134 also has a threaded parameter which will engage a threaded surface of body member 132. However, any conventional method of attachment could be used to connect rear plate 134 to body member

132. Such methods could include but are not limited to attachment with screws or pins, welding, or simply forming rear plate 134 as an integral part of body member 132 through casting, milling or other means.

The cross-sectional view of FIG. 14 illustrates the manner in which the camera adapter

130 will be mounted on eye piece receptacle 10 of an eye examining unit such as a conventional slit lamp (see FIG. 1 illustrating an eye piece receptacle 10). Once eye piece 143

is secured in adapter 130, eye piece 143 is inserted into eye piece receptacle 10 and body member 132 slides over the outer shoulder of eye piece receptacle 10 and eye piece receptacle

10 is seated against the inner surface of retaining member 140. This manner of attachment will

be sufficient to maintain adapter 130 in connection with the slip lamp during the course of a

normal eye examination procedure.

FIG. 15 illustrates modification of the embodiment disclosed in FIGS. 13 and 14. This embodiment allows cameras significantly larger than the V2" CCD micro-camera discussed above to be employed with adapter 130. Body member 132 includes a retaining member (not

shown), adjusting slot 133, and tightening screw 141 similar to the embodiment of FIGS. 13

and 14. However, the embodiment of FIG. 15 differs in that it also comprises a lens support frame 148 which includes support frame back plate 153 and sliding frame leg 149. Sliding

frame leg 149 will have a somewhat arcuate shape which will conform to the shape of lens 147 in order to provide a more contoured platform on which lens 147 may rest. Support frame

back plate 153 will have a conventional camera mount 152 or other suitable means for securing camera 7 and lens 147 to lens support frame 148. Camera mount 152 will include threads 154 for engaging camera 7 and while not seen in FIG. 15, will include threads adapted to engage

threads 151 of lens 147. To position lens 147 properly against body member 132, support leg

149 will engage channel 150 which is formed in body member 132 and adapted to receive

support leg 149. Support leg 149 can then be inserted into channel 150 to the extent necessary

to position lens 147 against body 130. While not shown, a set screw or any other conventional

means may be used to secure support leg 149 inside of channel 150. In addition to the

adapter members disclosed above, FIG. 1 illustrates how the present invention includes a means of positioning a light filter 84 between the eye being examined and the light source 87

used in illuminating the eye. This filter 84 will act as an exciter filter for use in angiography

procedures. As previously described, filter 84 filters out all wavelengths of light except that

wavelength which excites the fluorescein or ICG dye traveling through the blood vessels of the patients eyes.

In the eye examination unit 1 shown in Fig. 1, exciter filter 84 is positioned between

light source 87 and light directing mirror 88. As seen in FIG. 9, exciter filter 84 comprises

filter clamp 89, pivoting arm 86 pivotally attached to filter clamp 89, and exciter filter lens 85.

By being positioned on pivoting arm 86, exciter filter lens 85 can be placed in the light path

when fluorescein or ICG angiography is being performed. Alternatively, exciter filter lens 85

can be removed from the light path when other conventional examinations are being performed

with the slit lamp 2. As previously discussed, fluorescein angiography will employ a blue filter

lens and ICG angiography will employ a infra-red filter lens. It can be seen that exciter filter

84, when used in conjunction with barrier filters positioned in the camera adapter, converts the

conventional slit lamp 2 into an expedient and useful device for performing angiography

procedures. While the present invention includes both embodiments utilizing beam splitting prisms

and embodiments not utilizing prisms, those embodiments not utilizing prisms may be more

advantageous when performing angiography procedures. The more light that is reflected from

the eye to the camera, the more distinct will be the image of the dye illuminated blood vessels. However, when a device uses a beam splitting prism to redirect the light path, a significant

fraction of the light will be directed away from the camera. Therefore it is expected that embodiments not utilizing a beam splitting prism will provide a superior image, particularly in low light angiography.

From the above described embodiments, those skilled in the art will recognize the present invention allows an eye examiner to record a straight on or an in-line view of the eye.

This in-line view of the eye will allow the retina or rearward area of the eye to be clearly recorded. A camera not positioned in-line with the eye, such as a camera positioned to one side of the eye, will seriously limit what, if any, rearward areas of the eye may be recorded.

Finally, while many parts of the present invention have been described in terms of

specific embodiments, it is anticipated that still further alterations and modifications thereof

will no doubt become apparent to those skilled in the art. It is therefore intended that the following claims be inteφreted as covering all such alterations and modifications as fall within the true spirit and scope of the invention.

Claims

CLAIMSI claim:

1. A portable visual recording eye examining unit comprising: a. an eye examination device having a light source and a viewing element; b. an adapter member connectable to said viewing element; and c. a camera attached to said adapter member.

2. A portable visual recording eye examining device according to claim 1, wherein said adapter member has a light filter element for use in angiography examination.

3. A portable visual recording eye examining device according to claim 2, wherein said filter element is removably positioned between the eye being examined and said camera.

4. A portable visual recording eye examining device according to claim 1, wherein said eye examination unit is a converging optics slit lamp.

5. A portable visual recording eye examining unit according to claim 1, wherein: a. said viewing element comprises an eyepiece receptacle for a removable eyepiece; - b. said adapter member has a viewing tube that is positioned in said eyepiece

receptacle; and c. said camera is attached to said adapter member.

6. A portable visual recording eye examining unit according to claim 1, wherein: a. said viewing element comprises a removable eyepiece; b. said removable eye piece is connected to said adapter member; and c. said camera is attached to said adapter member.

7. A portable visual recording eye examining unit according to claim 5, wherein a video camera is wired to a display screen allowing the examiner to indirectly view the eye being examined.

8. A portable visual recording eye examining unit according to claim 1, wherein said adapter member comprises:

a. a viewing tube having a line of sight from a fixed eye piece to the eye under examination; and

b. a neck portion having a line of sight from the eye under examination to a camera.

9. A portable visual recording eye examining unit according to claim 8, wherein said adapter further comprises a prism cube beam splitter in the line of sight of said viewing tube and neck portion, producing a simultaneous line of sight from the eye under examination to

said fixed eye piece and said camera.

10. A portable visual recording eye examining unit according to claim 1, wherein said

adapter member comprises:

a. a clamp member; and

b. a camera frame member pivotally connected to said clamp member.

11. A portable visual recording eye examining unit according to claim 1, wherein said

adapter member comprises: a. an viewing tube having a first line of sight; b. a prism directing said first line of sight to a second line of sight;

12. A camera adapter for an eye examining unit comprising: a. a body with a front and rear aperture; b. said front aperture being formed to matingly receive an eye piece of an eye

examining unit; c. said rear aperture being formed to receive a camera lens.

13. The camera adapter for an eye examining unit according to claim 12, wherein said front

aperture has a shoulder and said eye piece has an eye piece ring such that said eye piece ring

securely engages said shoulder.

14. The camera adapter for an eye examining unit according to claim 12, wherein said eye piece is the eye piece ofa conventional converging optics slit lamp.

15. The camera adapter for an eye examining unit of claim 13 wherein said rear aperture has a micro-camera attached thereto.

16. A camera adapter for an eye examining unit comprising.

a. a clamp member; and

b. a camera frame member pivotally connected to said clamp member.

17. The camera adapter for an eye examining unit according to claim 16, wherein said clamp member has an aperture to grasp the outer diameter of an eye piece receptacle and a

tightening member to close said aperture.

18. The camera adapter for an eye examining unit according to claim 17, having a spacer element connected to said clamp member, said spacer element having an aperture adapted to

receive an eye piece ofan eye examining unit.

19. The camera adapter for an eye examining unit according to claim 18, wherein said

spacer element has a pin aperture for receiving a pivot pin.

20. The camera adapter for an eye examining unit according to claim 16, further having a

filter element attached thereto.

21. The camera adapter for an eye examining unit according to claim 20, wherein said filter

is positioned between said clamp member and said frame.

22. The camera adapter for an eye examining unit according to claim 16, wherein said

frame member has a plurality of extension legs and a camera connecting ring attached to said extension legs.

23. A camera adapter for an eye examination unit comprising:

a. an viewing tube having a first line of sight; b. a prism directing said first line of sight to a second line of sight; c. a camera mount positioned along said second line of sight.

24. The camera adapter for an eye examination unit according to claim 23, wherein a filter

is positioned between said prism and said camera mount.

25. The camera adapter for an eye examination unit according to claim 23, having a fixed eye piece and said prism directing a line of sight simultaneously to said fixed eye piece and said

camera mount.

26. A camera adapter for an eye examination unit comprising.

a. a body member forming an aperture to grip an eye piece receptacle;

b. a rear plate connected to said body member; c. a camera sleeve extending from said rear plate.

27. The camera adapter for an eye examination unit according to claim 26, wherein said

body has a flange allowing said aperture to be tightened on an eye piece receptacle.

28. The camera adapter for an eye examination unit according to claim 26, wherein said

body has a filter channel formed therein.

29. The camera adapter for an eye examination unit according to claim 26, wherein said

body further comprises: a. a clamping ring; b. a block formed on said claiming ring; c. a forward plate connected to said block; and d. a filter channel formed in said block and forward plate.

30. The camera adapter for an eye examination unit according to claim 29, wherein said clamping ring has a flange attached thereto for tightening said clamping ring on an eye piece receptacle.

31. The camera adapter for an eye examination unit according to claim 29, wherein said

camera sleeve has a tightening device adapted for securing a camera in said camera sleeve.

32. A portable visual recording eye examining device according to claim 3, further having a second light filter element removably positioned in a light path between said light source and the eye being examined.

33. An angiography filter assembly for reversibly converting a conventional slit lamp into an angiography examining unit, said angiography filter assembly comprising: a. a filter lens; b. a filter arm adapted to removably position said filter lens between a light source on said slit lamp and an eye under examination; and c. a clamp adapted to secure said filter arm to said slit lamp.

34. An angiography filter assembly according to claim 33 further comprising a barrier filter positioned between an eye under examination and a viewing element of said slit lamp.

35. A camera adapter for an eye examination unit comprising: a. a body member forming an aperture sized to receive an eye piece of an eye

examination unit; b. a rear plate connected to said body member, said rear plate forming an aperture such that a camera may be operatively connected to said rear plate.

36. The camera adapter for an eye examination unit according to claim 35, wherein said body includes an eye piece retaining member.

37. The camera adapter for an eye examination unit according to claim 35, wherein said

rear plate has a camera sleeve attached thereto.

38. The camera adapter for an eye examination unit according to claim 36, wherein said eye piece retaining member is ring shaped and sized to be positionable inside said body.

39. The camera adapter for an eye examination unit according to claim 38, wherein said

body has an adjusting slot and a positioning device engages said slot and said eye piece retaining member.

40. The camera adapter for an eye examination unit according to claim 39, wherein said positioning device is a screw member.

41. The camera adapter for an eye examination unit according to claim 35, wherein said

body has a filter channel formed therein.

42. The camera adapter for an eye examination unit according to claim 35, wherein said

body has a wall positioned between said rear plate and an eye piece retaining member.

43. A camera adapter for an eye examination unit comprising: a. a body member having a means to receive an eye piece receptacle;

b. a camera connecting means such that a camera may be operatively connected

to said body.

44. The camera adapter for an eye examination unit according to claim 43, wherein said

body includes an eye piece retaining means.

45. The camera adapter for an eye examination unit according to claim 44, wherein said

eye piece retaining means is sized to be positionable inside said body.

46. The camera adapter for an eye examination unit according to claim 44, wherein said body includes a means for adjusting said eye piece retaining member.

47. The camera adapter for an eye examination unit according to claim 43, wherein said

body has a filter means connected thereto.

48. A camera adapter for an eye examination unit comprising:

a. a body member forming an aperture sized to receive an eye piece receptacle;

b. a lens support frame connected to said body member.

49. The camera adapter for an eye examination unit according to claim 48, wherein said lens support frame includes a back plate and a support leg connecting said support frame with said body.

50. The camera adapter for an eye examination unit according to claim 49, wherein said

back plate forms an aperture for receiving a camera lens.

51. The camera adapter for an eye examination unit according to claim 49, wherein said body has a support leg aperture for slidably receiving said support leg.

52. The camera adapter for an eye examination unit according to claim 49, wherein said

back plate contains conventional camera mount.

53. The camera adapter for an eye examination unit according to claim 49, wherein said

back plate has a threaded aperture sized to matingly receive the threads of a conventional camera lens.

54. A process for performing angiography using a conventional slit lamp having a light source, a eye piece, and an eye piece receptacle, said process comprising the steps of: a. positioning an exciter filter on said slit lamp between said light source and an eye under examination; b. positioning a camera adapter containing said eye piece to engage said receptacle

piece receptacle; and c. positioning a barrier filter between an eye under examination and a camera attached to said camera adapter.