Artificial tears
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to devices for applying fluid to biological tissue and more particularly to apparatus which instills an aqueous solution to the surface of the eyeballs. The invention introduces artificial tear fluid to relieve the discomfort and potential ocular damage caused by chronic dry-eye condition, which is especially uncomfortable in elderly people. The invention also provides a corresponding method to treat eye dryness. 
     Many people suffer from a lack of eye moisture. Even though artificial tear solutions increase eye moisture and relieve discomfort, the application of such artificial tear solutions provides only temporary relief and therefore dry-eye sufferers commonly apply artificial tear solution to their eyes several times within the course of a day. The burden and interruption caused by frequent applications of eye drops is not conducive to maintain a proper moisture level and to apply the required dosages. 
     The present invention also finds use in applying an active medicinal agent dissolved in a volume of fluid administered to the eye. Fluids with active medical ingredients require careful control of the quantity of fluid administered. It generally is difficult, with manual application of the fluid using an eyedropper, to control the number of drops introduced to the eye. 
     Some eyedroppers exist with a fluid chamber having a threaded piston that screws within a correspondingly threaded cylinder. When the piston is advanced within the cylinder and held in a particular position, a predetermined volume of fluid is expelled from the chamber. However, due to the complicated structure of these devices, their bulkiness make them more cumbersome than typical eyedroppers. 
     Other devices have been developed to deliver fluid to an eyeball. These devices typically work by pumping fluid from a reservoir through a tube that has a distal end positioned adjacent to the eye. In some instances, the tube is surgically implanted under the skin. It begins at a fluid reservoir positioned, for example, at the lumbar region and ends adjacent the eye. These devices are cumbersome and invasive and the mechanism needed to pump the fluid through the tube is bulky and requires a heavy and bulky power source. Furthermore, control problems result from having to pump fluid to the eye through a relatively lengthy tube. Furthermore, fluid flow can easily be disrupted by patient movement and by inadvertent pinching or collapsing of the delivery tube. 
     In summary, the prior art has been characterized by apparatus that applies fluid droplets at a rapid and nonuniform localized flow so that such treatment/characteristic of the prior art causes non-uniform flooding on the exposed eyeball with damage to the eyeball resulting from the rapid, non-uniform application of moisture to the dry eyeball requiring treatment. 
     2. State of the Prior Art 
     U.S. Pat. No. 2,527,947 to Loos, issued Oct. 31, 1950, discloses a laminated eye protector comprising a flexible multiple ply pad consisting of an outer layer of relatively thick fabric which is relatively impervious to sun rays and moisture and is heat absorptive, an intermediate layer of absorbent material and an inner layer of relatively loosely woven fabric. The inner layer is porous to permit medication or water in the intermediate layer to travel through the inner layer to the eyeball surface. This patented device does not evaporate eye protecting moisture into a chamber immediately outside and surrounding the eyeball. 
     U.S. Pat. No. 3,826,258 to Abraham, issued Jul. 30, 1974, shows eye treatment apparatus that comprises a very small number of gradually released medicine carriers in a saline or antiseptic solution. The invention defined in this patent discloses a prepackaged ampoule-like dropper and does not provide means for evaporating an eye treating fluid within a chamber formed between an eyeglass frame on one hand and the eye and cheek of a user on the other hand. 
     U.S. Pat. No. 3,902,486 to Guichard, issued Sep. 2, 1975, relates to a portable nasal diffuser and is mentioned because this patent was reported in a novelty search. It would not be obvious to use a portable nasal diffuser to apply moisture to a dry eyeball surface. 
     U.S. Pat. No. 4,573,982 to Forbes, et al., issued Mar. 4, 1986, discloses an eyeglass frame constructed and arranged to apply a unit dose ophthalmic drug in liquid form. The liquid is applied directly to the eye as discrete droplets that treat the eyeball surface non-uniformly. A portion of the eyeball so treated remains dry after such treatment so that the dry eyeball problem is not fully corrected. 
     U.S. Pat. No. 4,908,024 to Py, issued Mar. 13, 1990, discloses an ocular treatment apparatus that is formed by a frame worn by a patient to support one or two light-deviation apparatus. The patient rotates his eyes upward and the light-deviation apparatus permits him to observe the lower ocular area to apply ocular treatment material in a location normally not seen by the wearer. 
     U.S. Pat. No. 5,171,306 to Vo, issued Dec. 15, 1992, discloses an eye drop delivery system for administering eye drops to at least one eye of a user and comprises a fluid reservoir for holding a supply of eye drop fluid, a tube for conducting eye drop fluid from the fluid reservoir to at least one eye of the user and fluid driving apparatus for continuously urging eye drop fluid from the fluid reservoir to at least one distal end of the tube and fluid control apparatus for successfully permitting eye drop fluid to flow freely from the tube. The fluid control means causes individual drops of eye drop fluid to be applied to the eye of the wearer. 
     U.S. Pat. No. 5,368,582 to Batera, issued Nov. 29, 1994, discloses a spectacle-like device that mounts a system of pump elements that can project droplets of liquid onto a wearer&#39;s eye. The use of pump elements complicates the structure of the device and does not suggest the slow, uniform application of evaporated fluid into a chamber adjacent to and surrounding the eyeballs. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present invention provides means for providing a &#34;dead space&#34; in front of the eyes. Moisture absorbed by a moisture absorbing material such as a cotton plug carried by a fluid impervious eyeglass frame is evaporated and released through a fluid pervious surface of a hollow frame when evaporated from the absorbent material or through apertures in an apertured cartridge reservoir fitted to the inside structure of a spectacle frame or within a slide-on passive reservoir attached to the temple of the spectacle frame. 
     The constant passive evaporation of the eye treating fluid from the absorbent material reservoir supported directly within the spectacle frame or on a replaceable apertured cartridge reservoir fitted to the spectacle frame causes the environment in contact with the eye to develop a high humidity environment of fluid moving more slowly than prior art devices to which the eyeballs are exposed. This slow fluid flow in the so-called &#34;dead space&#34; in front of a person&#39;s eyes counteracts the tendency of the eyeballs to become dry in response to the flow of air that is of relatively low humidity in contact with the outer surface of the eyeballs. 
     The present invention applies moisture to the surfaces of the eyeballs by a slower, more uniform and constant flow of evaporated moisture rather than pulses of pumped moisture or discrete drops applied to spaced areas of the eyeballs undergoing treatment of dry eye. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings that form part of the description of preferred embodiments of this invention, 
     FIG. 1 is a fragmentary perspective view of a first embodiment of an eyeglass frame showing how a fluid absorbing member in the form of a porous plug may be supported by an eyeglass frame for storing said fluid within a cylinder which is removably attached to interior surface portions of said frame, which interior surface portions are apertured to permit evaporated liquid to be delivered through said apertures into a so-called &#34;dead space&#34; chamber formed between the eyeglass frame on one hand and the eyes and cheeks of a wearer on the other hand. 
     FIG. 2 is a perspective view of a plug storing cartridge that is apertured to permit a constant low pressure outflow of evaporated fluid into the &#34;dead space&#34; chamber and is included in the eye treatment embodiment of FIG. 1. 
     FIG. 3 is a cross-section view taken along the line 3--3 of FIG. 2. 
     FIG. 4 is a side view of an eyeglass frame showing an alternate embodiment of this invention wherein the moisture absorbing member forms a side barrier so that the moisture absorbed within the moisture absorbing medium such as the cotton plug may be evaporated through a series of apertures in a side wall of the eyeglass frame that face said &#34;dead space&#34; chamber. 
     FIG. 5 is a cross-section view taken along the line 5--5 of FIG. 4. 
     FIG. 6 is a top view of the eyeglass frame of FIGS. 4 and 5. 
     FIG. 7 is a perspective view of a third embodiment wherein the inner walls of the opposite temples are hollow and have fluid pervious inner walls to permit ocular treatment fluid to seep into the so-called &#34;dead space&#34; chamber behind the lenses of the eyeglass frame from a moisture-impregnated member within the hollow temples. 
     FIG. 8 is a sectional view taken along the line 8--8 of FIG. 7. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     The drawings depict various illustrative embodiments of this invention. 
     Referring to the drawings, FIGS. 1, 2 and 3 show an eyeglass frame 10 having a left temple 12 and a portion of a right temple 14. Left temple 12 widens to form an enlarged left front temple portion 16 and right temple 14 enlarges to form an enlarged right front temple portion 18 seen in FIG. 1. 
     Eyeglass frame 10 forms a substantially horizontal front roof portion 20 and substantially horizontal lower lens holding portion comprising subportions 21 and 22 which latter are separated to form a nose opening 23 to separate the lower lens holding portion into two subportions 21 and 22 that support left lens 24 and right lens 26, respectively. Nose opening 23 extends generally in a vertical plane and includes a pair of diverging lens holding portions 27 and 28 which extend downward from roof portion 20 toward the bottom lens holding subportions 21 and 22. 
     The inner end of the horizontally extending front roof portion 20 is arranged to conform to the shape of the forehead of a wearer of the eyeglass frame 10. Thus the front roof portion 20 serves as a roof of a so-called &#34;dead space&#34; chamber and the lens holding portions 21 and 22 cooperate with lenses 24 and 26 to serve as a vertical front wall of the &#34;dead space&#34; chamber. The nose of the wearer fits into the recess of nose opening 23 and the enlarged left and right front portions 16 and 18 of left temple 12 and right temple 14, respectively, cooperate with the cheek and eyes of the wearer to provide side walls for the chamber within which a relatively stagnant atmosphere is located. 
     The inner surface of enlarged left front portion 16 and enlarged right front portion 18 support a plurality of vertically aligned sets of flexible clips 30 which are readily distorted to receive an apertured cartridge 32 at each front inner corner of the eyeglass frame 10. The apertured cartridges 32 are filled with a plug 34 of fluid absorbent material such as a cotton plug. Apertures 36 in the walls of the apertured cartridge 32 provide passageways for the removal of evaporated water or other liquid from the plug 34 of fluid absorbent material into the chamber formed between the upper face and eye portions of the wearer and the eyeglass frame 10. 
     In the first embodiment of FIGS. 1, 2 and 3, apertured cartridges 32 are insertable in a set of vertically aligned clips 30 near each front corner of the eyeglass frame 10 to provide ready insertion into each set of clips 30 of an apertured cartridge 32, each containing a different plug 34 of fluid absorbent material. Moisture absorbed within the plug 34 is gradually evaporated over a period of time without requiring any pumping means and the evaporated fluid escapes through apertures 36 of the apertured cartridges 32 into the chamber formed between the eyeglass frame 10 and the face and eyes of the wearer. The bottom lens holding subportions 21, 22 are of arcuate shape so that they form the bottom of the chamber between the eyeglass frame 10 and the portion of the face of the wearer that includes the wearer&#39;s eyes. 
     Referring to FIGS. 4, 5 and 6, it is noted that a left temple 112 extends alongside an enlarged left front portion 116 and a right temple 114 extends alongside an enlarged right front portion 118 of the frame. Enlarged portions 116 and 118 have fluid pervious inner surfaces 117 and 119, respectively that serve the same purpose as apertures 36 of apertured cartridges 32 facing inward toward the &#34;dead space&#34; chamber of the embodiment of FIGS. 1, 2 and 3. Large front portions 116 and 118 are shown as hollow with the interior facing fluid pervious surfaces of the hollow large front portions 116 and 118 serving the purpose of apertures 36 of cartridges 32 of the first embodiment. In addition, plugs 134 of fluid absorbent material within hollow large front portions 116 and 118 serve the same purpose as plugs 34 of the first embodiment, and apertures 136 of the FIGS. 4, 5 and 6 embodiment serve the same purpose as the inwardly facing apertures 36 of the first embodiment. Left temple 12 extends through a tunnel 137 exteriorly of enlarged left front portion 116 of left temple 12 and a tunnel 138 is attached to the exterior surface of enlarged right front portion 118 of temple 14 so that left temple 12 extends through left tunnel 137 and right temple 14 extends through right tunnel 138. 
     In the embodiment of FIGS. 7 and 8, a hollow body 232 serves the purpose of apertured cartridge 32 of the first embodiment or hollow cartridge 132 of the second embodiment and a plug 234 filled with fluid absorbent material contains fluid which evaporates and escapes as a slow gentle fluid flow through apertures 236 to increase the humidity within the atmosphere or environment in the &#34;dead space&#34; chamber between the eyes and face of the wearer on one hand and the eyeglass frame on the other hand. 
     The frame of any of the foregoing embodiments may be vented by applying vent holes to any wall of the frame facing away from the &#34;dead air&#34; space chamber when necessitated by hyper-humidity within the chamber. Under such circumstances, the vent holes prevent fogging of the lenses. 
     Conforming to the provisions of the patent statutes, applicant has provided an explanation of the principle, preferred construction and mode of operation of this invention and has illustrated and described what is now considered to be its best embodiments. It is understood, however, that within the scope of the claimed subject matter that follows, the invention may be set forth otherwise than as specifically illustrated and described in this specification.