A trans scleral illuminator with retractable shaft

Abstract

A scleral depressor and illuminator is disclosed. The instrument includes a handle having a rechargeable battery, a rigid but flexible shaft, and a distal probe tip portion. The probe tip may be partially spherical in shape. The probe tip includes a transparent window that is arranged laterally to a long axis of the shaft, and is opaque in all other directions such that the probe tip launches a beam that is oriented transverse to the long axis of the shaft.

Description

[0001] Attorney Docket: 185288.00004

[0002] A TRANS SCLERAL ILLUMINATOR WITH RETRACTABLE SHAFT

[0003] Cross Reference to Related Applications

[0004] This application claims priority to U.S. Provisional Patent Application 63 / 720,512, filed on November 14, 2024 and entitled 'A Trans Scleral Illuminator With Retractable Shaft”. This application also claims priority to U.S. Provisional Application No. 63 / 709,277, Filed on October 18, 2024 and entitled “A Trans Scleral Illuminator”. The entirety of both aforementioned applications is incorporated by reference herein in their entireties.

[0005] Field of the Invention

[0006] This invention relates to a miniature, efficient and light weight solid state light source for trans scleral illumination of the eye. More particularly, the present invention provides for an untethered, handheld portable probe, which can be disposable, non-sterile, or of limited reuse. The probe may have a spherical, semi-spherical or other curved volume illumination housing placed in contact with the eye which can direct illumination into the eye, allowing a surgeon to view the vitreous and retina with an indirect ophthalmoscope.

[0007] Background

[0008] Conventionally, scleral depressors are used in conjunction with a binocular indirect (head worn) ophthalmoscope and a handheld condensing lens (+30-40 diopters) to visualize the peripheral retina in order to search for retinal holes, breaks and or tears. Holes, breaks and or tears are treated using a laser indirect ophthalmoscope (LIO). Scleral depressors distort the eye wall inward and put the peripheral retina in profile which helps in visualization, especially for small flap tears. Trans-scleral illumination (that is, illumination of the interior structures of the eye indirectly, through the sclera or white part of the eye) eliminates effects from coaxial inbound light from a slit lamp, microscope, or the binocular indirect, all of which can interact with cornea, lens, intraocular lens, and or vitreous humor producing scatter and making stereo visualization more difficult.

[0009] Patients who might benefit from such an exam include prematurely bom infants at risk of retinopathy of prematurity. ROP is one of the leading preventable causes of childhood blindness. Attorney Docket: 185288.00004

[0010] Such exams are ty pically performed on premature infants (generally <32 weeks gestational age or <1500 g birth weight). ROP occurs when immature retinal blood vessels grow abnormally, potentially leading to retinal detachment and vision loss.

[0011] Conventionally, several instruments have been suggested to provide trans scleral illumination. Several of these instruments are shown in FIG. 1. FIG. 1 A shows a passive, non-illuminated device, which has a ball appendage at one end and a hammer-like portion at an opposite end. This device provides no illumination itself, and instead relies on ambient illumination or a supplemental illuminator that must be directed at the sclera, making the device difficult to use. FIG. IB shows a trans scleral illuminator having a handle portion, a linear portion (e.g., a wide gauge hypodermic needle, or a polymer light pipe) topped with a transparent sphere that emits light. The handle portion connects the linear portion to some light source, such as fiber optic cable that is optically coupled to some remote light source. Generally, in illuminators of the type shown in IB, light is provided through fiber optics to a distal tip of the device, where it is emitted isotopically through a generally spherical distal tip, which may be used as a probe to deflect the sclera. The disadvantage of this device is the back scatter from the sphere; some of which is within the surgeon's field of view and makes subtle judgements in the eye more difficult.

[0012] There is an improved conventional device, the TID Pharos illuminated scleral depressor from Vortex Surgical. In this device there is a remote light source (located at the handle of the device or in some external illuminator connected to the device by fiber optics), which is coupled to a light pipe. A transparent sphere can be mounted to the distal end of the light pipe, thereby causing light to be radiated in all directions in all directions. In an alternative configuration of this illuminator, the transparent sphere includes an angled reflector or prism (e.g., a TIR prism or Brewster window)), which couples light out of the device in a sideways direction, i.e., perpendicular to the long axis of the light pipe and handle. While this device is a further improvement, there is still substantial back scattered light that escapes the transparent sphere in multiple directions, which may interfere with the physician’s observation. Further improvement over these conventional approaches is required, particularly for difficult patient populations.

[0013] For example, the small size and anatomy of infant patients presents challenges to conventional devices. For infant patients, a small infant eyelid speculum is used to hold the eye open and a scleral depressor helps visualize the peripheral retina. The ophthalmologist ty pically uses an indirect ophthalmoscope with a 20D or 28D condensing lens to obtain a Attorney Docket: 185288.00004 stereoscopic view of the retina. The examiner systematically inspects each eye from the posterior pole (optic disc and macula) outward to the periphery, noting: the zone of retinal vascularization (I, II, or III), the stage of disease (1 through 5, from demarcation line to total retinal detachment), and the presence or absence of plus disease (vessel dilation / tortuosity in posterior pole), or, any hemorrhages, fibrovascular proliferation, or traction.

[0014] In certain patient populations, particularly older individuals at risk for ocular disorders such as retinal tears, retinal detachments, and vitreoretinal interface abnormalities, anatomical changes within the orbit may present unique challenges to examination. With advancing age, orbital fat atrophy and tightening of periocular tissues often result in reduced orbital volume and limited space for instrumentation. These conditions can make conventional scleral depression uncomfortable and technically difficult, limiting visualization of the far peripheral retina.

[0015] A need continues to exist for an instrument that can provide illumination of internal eye structures, through the sclera, that minimizes stray light and provides a compact, comfortable probe configuration usable in tight spaces.

[0016] Brief Summan'

[0017] In one embodiment, the invention includes an instrument for deflecting and illuminating the sclera of a human eye. The instrument includes a handle, which may contain a battery and drive electronics for illuminating an LED. The handle may also include a switch for selectively electrically coupling the battery or drive electronics to an LED, as described below. The handle is coupled to a linear section or rod, which extends away from the handle in a direction parallel to a long axis of the handle. The rod may be substantially rigid or still slightly flexible. The linear section or rod may carry conductors that electrically couple the drive electronics to an LED light source. At an end, specifically a distal end of the rod, a spherical assembly is provided. The spherical assembly comprises a hollow portion that is a portion of a hollow sphere. The majority of the hollow portion is opaque or non-transmissive to light. Preferably, the majority portion of the hollow portion comprises metal such as stainless steel, but an opaque polymeric material may also be used. The hollow portion also has a spherical cap portion. The term “spherical cap” refers to a portion of a sphere cut-off from the sphere by one, single plane. The height of the spherical cap is defined as a distance equal to the largest value of thickness of the spherical cap measured perpendicularly to the Attorney Docket: 185288.00004 planar surface of the spherical cap. The spherical cap portion comprises a transparent material such as glass, quartz, sapphire, or preferably, an optical transparent polymeric material such as acrylic, polycarbonate, polystyrene, or COC. Together when the transparent spherical cap portion is assembled with the opaque portion, the distal tip of the instrument is substantially spherical, but is not completely spherical because there is a junction between the distal end of the rod and the spherical assembly.

[0018] Within the spherical assembly is an LED light source. Preferably, the LED light source is a "white" LED, i.e.. a blue-LED pumped phosphor, which emits light over a broad visible spectrum. Alternatively, the LED may be red, green, blue or some combination of these colors. The LED may include red, green and blue chips, and may be driven with the aid of a controller to emit combinations of those colors. The LED is preferably arranged behind the transparent spherical cap so that it emits light out of the transparent spherical cap, but such that light is blocked from emission by the remainder of the hollow spherical portion. The transparent spherical cap is located on a lateral side of the instrument such that light is emitted substantially perpendicularly relative to the long axis of the instrument, e.g., the long axis of the rod and handle.

[0019] An instrument according to the foregoing description has certain advantages. The spherical tip of the instrument enables the sclera to be comfortably and safely manipulated, and the side emitted light may be used to illuminate the sclera and structures within the eye. By placing the LED light source within a largely opaque distal tip, the instrument avoids backscatter and stray light that limits the usability of conventional instruments.

[0020] Additionally, inventive embodiments address the shortcomings of conventional instruments for challenging patient populations as described above. Those limitations are addressed by enabling indirect visualization of peripheral retinal structures without the degree of mechanical indentation typically required for scleral depression. The miniature distal light engine or other illumination probe may be configured for subsurface trans-scleral light delivery7, producing diffuse illumination that enhances peripheral retinal contrast while minimizing patient discomfort. In this manner, the device facilitates detailed examination of the retinal periphery in patients with tight orbits or diminished orbital fat, improving diagnostic capability in elderly or post-surgical eyes.

[0021] The foregoing and other aspects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred Attorney Docket: 185288.00004 embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention.

[0022] Brief Description of the Drawings

[0023] The figure labeled Prior Art shows several conventional scleral illumination instruments.

[0024] FIG. 1 illustrates two conventional scleral probes.

[0025] FIG 2 shows a face-on and side views of one embodiment of the invention.

[0026] FIG. 3 shows a cross section of a light engine and a cross section of the shaft of one embodiment of the invention, showing wiring in cross section view A and B.

[0027] FIG. 4 shows an alternative embodiment of an illuminated scleral probe, where the shaft portion is retractable into the handle.

[0028] FIG. 5 shows an alternative embodiment of an illuminated scleral probe having a flex cable assembly coupling the probe end to the handle.

[0029] FIG. 6 shows an alternative embodiment of the invention where a distal section of the instrument is detachable and / or disposable.

[0030] FIG. 7 shows an alternative embodiment of the invention where a distal section of the handle includes finger ridges for easier manipulation.

[0031] FIG. 8 shows another alternative embodiment of the invention having a modified light engine where the light source is located in the handle.

[0032] FIG. 9 shows an alternative arrangement of a scleral probe having a recharging cradle.

[0033] FIG. 10 shows a collar assembly supporting a disposable 3-mirror contact lens.

[0034] Detailed Description of the Preferred Embodiments

[0035] The present disclosure is illustrated by way of examples, embodiments and the like and is not limited by the accompanying figures, in which like reference numbers, letters, or names indicate similar, although in some cases not identical, elements. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. The figures along with the detailed description are incorporated and form part of the specification and sen e to further illustrate examples, embodiments and the like, and explain various principles and advantages, in accordance with the present disclosure. Attorney Docket: 185288.00004

[0036] Reference throughout this specification to “one embodiment,'’ “an embodiment,’' or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrase “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. The described features, advantages, and characteristics may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments.

[0037] In one inventive embodiment, an illuminating scleral probe is provided. The probe includes one or more miniature solid-state sources such as LEDs, which are located within a spherical-like (i.e., a closed body having a spherical surface, but which may not be a complete sphere) housing located at a distal end of the device. This spherical body may include a light engine itself having the solid-state light source, and electrical connections. The spherical body is positioned at the distal end of a hollow shaft, which is attached to a handle. The light engine is electrically connected to a battery compartment in the handle of the device. The illumination exiting the spherical like housing at the tip directs illumination more or less exclusively orthogonally to the axis of the shaft supporting the ball like tip. That is to say, the window (which acts as a lens), the position of the LED and the opaque housing act, together, to define a sideways pointing beam. The beam made be characterized in a conventional manner, in that it will have a central propagation direction, along which the LED will have peak intensity, and additional light emitted into a range of angles around the central propagation angle such that the beam is a diverging cone. The central propagation direction of the beam, which will also generally be the average propagation direction all light within the beam, is oriented to the side, or perpendicularly with respect to the long axis of the device or a central long axis of the shaft (an axis running along the long dimension of the shaft in its center). The angular extent about this central propagation direction of the cone may be defined by its full width, half max (FWHM), that is, the angle relative to the central direction where the intensity has dropped to 50% of the maximum intensity at the center. This is typically how symmetrical beams are characterized.

[0038] Referring to the beam generated by the inventive embodiments, they will preferably be symmetrical and conical in shape, but this is not a requirement. They may also be asymmetrical Attorney Docket: 185288.00004 having one side or the other obscured or cut off such that, their cross-sectional irradiance pattern is non-circular. Preferably, however, the beam will be circular in cross section and conical along the direction of propagation. Assuming this, various beam angles are acceptable, for example, any range less than 180 degrees is within the scope of the invention, however, a beam pattern that wide would not be preferred since it would include light that radiates directly back toward the eyes of the examining physician. A beam angle of no greater than 150 degrees is preferred, and tighter beams (e.g., 130 degrees, 120 degrees, 110 degrees, 100 degrees. 90 degrees, 80 degrees, 70 degrees, 60 degrees, 50 degrees 40 degrees, 30 degrees, 20 degrees orlO degrees) are better to achieve stray light control and glare minimization. Taking a 60 degree beam as an example, and working from a polar coordinate system where zero degrees elevation is the upward vertical direction of the central axis of the shaft, the beam would exist at between 60 and 120 degrees, with its central propagation axis at 90 degrees. The beam would be symmetrical and circular, so the azimuthal angles would be the same.

[0039] In use, the device tip, which is spherical in nature, allows for smooth repositioning of the illumination into the eye surface by the surgeon whose view is directed through the pupil of the patient eye.

[0040] In certain embodiments, a trans-scleral illuminator assembly is dimensioned and contoured to accommodate the anatomical constraints of smaller or tighter orbits. The probe tip may be formed with a reduced diameter and a low-profile curvature to permit comfortable insertion and manipulation along the scleral surface without exerting undue pressure on the globe or eyelids. The distal housing enclosing the light engine may assume a spherical or ellipsoidal form, optimized for both light dispersion and mechanical clearance within the orbital margins.

[0041] The handle assembly can be angled or ergonomically offset relative to the probe axis to enhance maneuverability in restricted spaces and to maintain a stable hand position during examination. In some variations, the handle includes textured or elastomeric grip surfaces and balanced mass distribution to minimize operator fatigue during prolonged procedures.

[0042] Thermal management is achieved by conduction through the probe body and handle, which may be fabricated from biocompatible metals or thermally conductive polymers, thereby dissipating heat from the solid-state light source while maintaining external surface temperatures within safe operating limits. These features collectively facilitate precise Attorney Docket: 185288.00004 illumination of peripheral retinal regions while accommodating anatomical variations across patient populations.

[0043] The present embodiments are directed to a trans-scleral illuminator incorporating a miniature solid-state light source, such as one or more light-emitting diodes (LEDs), integrated within a generally spherical or spheroidal housing. The illumination assembly, or light engine, comprises the light source together with associated electrically insulating and structural components.

[0044] In one embodiment, the light engine is positioned at the distal end of a hollow shaft coupled to a handle assembly, thereby permitting precise placement of the illumination source adjacent to the scleral surface. In another embodiment, the light source is disposed at the distal end of a flexible cable-like assembly that includes a mechanical stiffener to maintain positioning during use. In still another embodiment, the LED or other solid-state source is integrated directly within the handle assembly itself.

[0045] Collectively, the illumination-producing structures described herein constitute a miniature distal light engine suitable for providing localized, high-intensity trans-scleral illumination of ocular tissue.

[0046] A further embodiment involves one or more trans-scleral illuminators operatively coupled to a contact lens assembly. The contact lens may be of a simple type configured to conform to the comeal surface by means of an optical coupling medium such as methyl cellulose or another suitable compound, thereby neutralizing or minimizing the optical power of the cornea. Alternatively, the contact lens may comprise a multi-mirror design, such as a three- or four-mirror contact lens.

[0047] In this embodiment, the assembly including the attached trans-scleral illuminator secures the contact lens — of either type — and permits controlled rotational positioning of the lens to facilitate viewing of interior ocular regions. The illumination probe is positionable to provide optimized illumination relative to the observed region.

[0048] The described contact-lens-based assembly provides a wider field of view7of the ocular interior than direct observation with an indirect ophthalmoscope. Illumination from the trans- scleral source enters the eye through the scleral wall, thereby reducing back-scatter and glare associated with illumination entering through the pupil. This approach mitigates the deleterious effects of light scattering caused by age-related, pathological, or traumatic changes within anterior ocular and vitreous structures, improving both contrast and image uniformity. Attorney Docket: 185288.00004

[0049] The light engine may be electrically connected to a battery compartment in the handle of the device. The illumination exiting the spherical like housing at the tip directs illumination more or less orthogonally to the axis of the shaft supporting the ball like tip. In use the device tip which is spherical in nature allows for smooth repositioning of the illumination into the eye surface by the surgeon whose view is directed through the pupil of the patient eye.

[0050] The spherical like shape of the housing at the tip minimizes any abrasion to the eye surface. During an exam by the physician the tip will be positioned in numerous location on the eye's side surface. Constructed of 2 or more materials the spherical tip offers several advantages over fiber optics in a needle, and or direct viewing through the eye’s pupil.

[0051] Referring now to FIG. 2, there is shown front and side views of an ophthalmic instrument 200 according to one embodiment. As seen in FIG. 2, the instrument has a long axis (running vertically through the page of FIG. 2). At a proximal (bottom) end, the instrument has a handle 205, which may include a battery 225, such as a coin battery. The battery 225 may be arranged in a compartment as shown, and it may be removable for replacement or recharging. Alternatively, the battery may be fixed within the handle, in which case the handle may include a non-illustrated electrical charging port to enable charging of the battery. Charging of the battery' may be through some means that does not require a direct conductive connection or even physical contact, such as by an inductive charging arrangement as shown in FIG. 9. The handle may also include a switch 220, that closes and opens an electrical circuit that electrically couples the battery to the light engine and permits current to selectably flow from the battery7to the LED in the light engine. In the simplest case, the battery' may be selectably connected through the switch to a resistor and the LED in series, where the value of the resistor is chosen to achieve a predetermined current flow at a predetermined operating point of the LED. In other embodiments, the resistor may be variable (e.g., a potentiometer) to vary' current flow through the resistor to some degree, to achieve some level of adjustability of brightness. In these arrangements, controls for the variable resistor may also be located in the handle. In other arrangements, the device includes circuity to provide regulated current to the LED (e.g., a current regulator or driver). In preferred embodiments, the LED will be driven by pulse width modulation, where a PWM controller and associated circuitry powered by the battery7supplies pulsed current of a predetermined amount to the LED at one or more, or a continuously variable frequency. The intensity of the LED may thus be adjusted by varying the pulse width (i.e., the duty cycle) of the PWM signal. The PWM signal waveform may take various forms, e.g., square wave, triangular wave, etc. Attorney Docket: 185288.00004

[0052] In these embodiments, the handle may include a microcontroller and non-volatile storage (e.g., flash storage. EPROM, etc.), encoding computer readable instructions executable by the microprocessor enabling the microprocessor to cany out certain methods of driving or controlling the device. For example, the microprocessor, in accordance with the aforementioned instructions, may drive the LED in accordance with one or several user selectable PWM drive schemes (e.g., different drive schemes that result in different LED intensities). In the case where the LED source is one or more monochromatic LEDs (e.g., an RBG triad rather than a white LED), these programmable drive schemes may serve to select a variety of output colors at different intensities. Additionally, the microcontroller may monitor other parameters such as battery charge, number of uses, aggregate time of use since a given time, etc. In response to these sort of condition parameters, the microcontroller may take certain actions such as disabling the device, flashing the LED with a code that indicates that the user should take some action (e.g., recharge the device, sterilize the device, replace the tip, etc.).

[0053] The handle may include optional convenience features such as a pocket clip as shown.

[0054] The cross section of the handle 205 (i.e., perpendicular to the long or vertical axis) may have a variety of shapes. It may be circular, oval, lenticular, or as shown, a rounded rectangular shape. The shape and the orientation of the shape relative to the direction of light emission out of the distal end of the probe may be chosen such that the user of instrument can determine the direction of light emission from the position and orientation of the handle in the user’s hand. For example, in the embodiment of FIG. 2, the handle is a rectangular prism with rounded comers having a long (vertical) dimension, a rectangular longitudinal cross section, two wide sides (left and right and perpendicular to the plane of the figure), and two narrow sides (top and bottom and parallel to the plane of figure). The two wide flat sides may be used to determine the direction of light emission, which is perpendicular to the planes of both the wide sides. Generally, the aspect ratio between a first set of parallel sides and a second set of parallel sides may be used by the user to determine the emission direction of light being emitted from the instrument. Other features, such as the tactile features shown in the embodiments of FIGS. 5 and 7 may also be used to determine the direction of light emission.

[0055] At a distal (upper) end of the handle is a narrow shaft portion 210. Preferably, the shaft 210 is hollow^ and carries wiring electrically coupling the battery and switch (and the drive electronics) to the light engine in the spherical probe tip. The shaft extends from its proximal (bottom) end, where it is connected to the handle, to a distal end. where it is coupled to a hollow Attorney Docket: 185288.00004 spherical probe tip 215. The spherical probe tip is more accurately described as sphere-like, since the spherical shape is interrupted by its junction with the distal end of the shaft, and so the tip in this region may be flat, to accommodate threads or the like to mechanically join the shaft to the probe tip. Speaking in terms of polar coordinates, sphere like shapes that have upper spherical portions from 0 degrees (vertical) to between 100 and 170 degrees are acceptable and within the scope of the invention. Additionally, other rounded shapes may be used, such as ellipsoids and ovoids. More generally, the shape of the probe tip may vary on either side. For example, in preferred arrangement the shape of the probe tip that will be impinging on the sclera (the left hand side of the tip in the side view of FIG. 2) is spherical, but the shape of the other side, that will be impinging on the inside of the orbit or eyelid (the right hand side of the tip in the side view of FIG. 2) may have some other rounded shape. Additionally, even in the case where both sides are spherical, the radii of the sphere’s may have different radii, and / or their respective radii may not be in the same location. For example, the radius of the sclera side may be shorter than the radius of the orbit or eyelid side. In certain cases, the orbit or eyelid side may be flat (that is, shaped like a rectangular prism) as in the FIG. 5 embodiment. The comers and edges of this side preferably will have some relatively long radius such that the shape is somewhat rounded for the comfort of the patient. These shapes may be advantageous in that they decrease the overall width of the probe tip.

[0056] Preferably, the majority of the body of the spherical distal tip 215 is opaque such that it does not emit light from its interior. A portion of the spherical distal tip (i.e., a spherical cap portion separated from the larger spherical shape by a planar interface) is a transparent window, the outer surface of which has a partial spherical shape, as best seen in FIG. 3. Thus, the distal spherical tip has a first portion, which is a window preferably formed of glass, sapphire or plastic and is of a similar radius compared with a housing formed of a second material which is metal or plastic and not transparent. The first material is sealed to a second material which forms the body of the spherical tip containing the first material.

[0057] The composition of the distal spherical tip can be better seen in FIG. 3, which includes an inset a close up of the tip 315, marked “A”. As can be seen, a light engine is arranged inside the hollow distal tip, which comprises a transparent window portion 330 and a non-transparent housing portion 320. The light engine is, at least, one or more LEDs chips 335, preferably in a surface mountable package, electrically bonded to a stiff carrier board 340. The carrier board 340 provides a mechanical mounting surface for mounting the LED 335 within the hollow tip 315, and also electrically couples the electrical terminals of the LED (i.e., the anode and Attorney Docket: 185288.00004 cathode) to wires 345 that run dow n the shaft 310 of the instrument and into the handle 305 where they are connected to the battery 325 and the switch. The carrier board 340 may also comprise or be coupled to a non-illustrated heat sink arranged on a back side of the carrier board. The shaft 315 of the instrument is hollow to accommodate the wires, and the shaft 315 may also include a flexible stiffener 350, which preferably is some polymeric material but may also be a flexible copper rod. as discussed below. Possible arrangements for the wires 345 and the stiffener 350 are shown in the cross sectional drawings of the shaft at ”B“ and “C”.

[0058] Returning to the arrangement at the spherical distal tip 315, in the illustrated embodiment, the LED 335 faces the window 330 such that its light is emitted through the window, and the opaque (e.g., metal) portion of the tip 320 prevents light from being emitted in any direction other than through the window'. This arrangement is not limiting, however. In other embodiments, the LED may face upward, and its emitted light may reflect and scatter off the interior of the metal opaque portion of the tip, and may then be emitted through the side facing window'. Structures (e.g., scattering striations) or reflective material (e.g., white paint or titanium oxide) may be placed on the interior spherical surface of the first material (the opaque portion of the tip) to facilitate scattering and homogenization of the light prior to emission through the side window. To this end. the opaque housing (e.g., in the form of a hollow metal spherical shell coated on its inside surface with a highly Lambertian reflective coating) may effectively act as a partial integrating sphere. This may be helpful w here the LED is not a white LED, but rather, is a plurality of colored LEDs having slightly different angular emission patterns, which might be improved and made more uniform by reflecting within the spherical tip prior to emission.

[0059] Thus, in a preferred embodiment the sphere-like tip has a first transparent material forming a window of glass or plastic, and which has a similar radius, Rl, compared with the radius R2 of the portion formed of a second material. The second material is metal or plastic and the second portion of the tip formed of the second material is not transparent. The second material forms the body of the spherical like housing containing the first material.

[0060] Alternatively the sphere-like tip may be a single material, such as an optical plastic (COC, acrylic, polystyrene, polycarbonate, or any of the other plastics described throughout this disclosure), where most of the surface of the tip has been metalized or otherwise coated with an opaque coating, which may be a reflective coating. The window' portion as shown in FIG. 3 would not be coated, and therefore would remain transparent. Attorney Docket: 185288.00004

[0061] The combination of the side facing transparent window and the opaque remaining extent of the tip results in light exiting exclusively through the first material (the window material) in a sideways direction relative to the long axis of the instrument. Without any constraint, the LED will approximately emit light into a hemisphere (i.e., isotropically, but into a hemisphere). In the inventive arrangements, light is emitted into some solid angle having a central angular direction and a distribution around the central direction. The central direction is forced to be to the side, at 90 degrees, more or less, to the axis of the shaft.

[0062] As can be seen, in the preferred embodiment of the figures, the window is configured as a plano-convex lens, and so may have some optical power relative to other shapes (such as a spherical shell). In this preferred configuration, the power of the window element and the position of the LED may be chosen to focus to some degree the light being emitted from the instrument. Because the outer surface of the window has preferably the same radius as the opaque portion, and because the radius of the entirety of the tip will be dictated by non-optical concerns, this focusing functionality will be determined primarily by selecting the position of the LED behind the piano portion of the window. Again, however, this plano-convex window configuration is not limiting. In alternative embodiments, the window may be a spherical shell (i.e., spherical front and back surfaces with similar radii of curvature to the right of the window, forming a meniscus lens). The window may be a biconvex lens or a ball lens, for more focusing power. Additionally, the window may incorporate other optical surfaces, such as holographic optical elements, Fresnel lenses, TIR lenses or the like, however, preferably, the outside surface of the window is smooth because it is pressed against the patient’s eye.

[0063] It is contemplated that when the tip’s window is not in contact with the eye surface, the light being emitted from the window will be focused to some degree by optical power in the outward facing surface of the window. This will tend to produce a focused, directed beam, as the second surface, i.e., the inward facing or interior of the window, is piano. However, when the outwardly facing window surface is placed in contact with the eye with a slight force, such that the eye conforms to the window surface, the optical power of the outwardly facing surface of the window will be decreased. This is because that surface is effectively optically immersed in the eye material which has an index of refraction greater than 1. In this circumstance, there is less of an index difference between the eye’s index of refraction (about that of water or -1.33) and the window material, which may range from 1.2 to 1.7, but in most cases will be glass or plastic ranging from about 1.4 to 1.6. Because of this effective reduction in the focusing power of the window, when the tip is pressed into the eye, the light will be emitted Attorney Docket: 185288.00004 with a wider angular spread than when it is in air. This is advantageous because the illumination entering through the eye side will spread out within the eye’s interior to a greater degree. In order to facilitate this effect, the window material may be chosen, in some embodiments, to be similar to that of the eye, or at least, to be as low as practicable. Thus, one advantage of providing a spherical, convex probe surface through which light is emitted is, apart from patient comfort, that such a surface creates a tight directed beam with minimal stray light when the instrument is in air, but then creates a widely dispersed beam when pressed against the sclera. In some embodiments the index of refraction of the window lens is much higher than that of the eye, for example 2.00, to effectively narrow the beam of light once inside the eye. Physicians may have particular preferences for light distribution depending on anatomy or clinically relevant interest.

[0064] Generally, the size configuration of the probe tip will be determined in accordance with a set of dimensional and optical relationships between the transparent optical element and the surrounding housing.

[0065] In the light engine assembly according to an inventive embodiment may be configured follows: The first surface of the first material (i.e., the outward facing surface of the transparent window), has a radius of R1. Preferably this is equal to the radius of curvature of the surface of the remainder of the spherical tip (i.e., the non-transparent portion), R2. The first material (the window material) may be glass, or glass like material, such as sapphire which has a refractive index defined as Nl. The material of the opaque housing radius is defined as R2. The condition (1), (2) and (3) shown below show one set of acceptable ranges for these parameters, where the linear quantities are measured in millimeters:

[0066] O.5*|R1|< N1<4*|R1

[0067] (1)

[0068] R1 ~ R2

[0069] (2)

[0070] Nl ^1.45

[0071] (3)

[0072] While these constraints yield an ideal probe tip size of between 0.7mm and 6mm for an index 1.45 material, other configurations are possible, in particular, for other materials. In some embodiments, the radii of curvature of the window portion and the opaque portion may be unequal. In other embodiments, the diameter of the tip may exceed 6 mm, and may be any Attorney Docket: 185288.00004 diameter including and within the ranges of 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 mm. The index of refraction of the window portion may also be anything within the range of 1.7 to 1.2, and in particular, within 1.33 to 1.6.

[0073] That said, the conditions satisfied by the equations above results in a curvature and optical compatibility between the transparent optical element and the opaque housing, ensuring efficient light transmission through the distal tip while maintaining structural integrity7, minimizing internal reflection losses, and providing minimal form factor.

[0074] In a further embodiment the first material (i.e., the window or lens material) may be a moldable or formable optical plastic which include polymers such as: polymethacrylates, polyurethanes, polycarbonates, polystyrenes, urethane-acrylates and cyclic olefin copolymers. These have refractive indices in a medium or high range, 1.4 to 1.7, though some formulation may be higher or lower than this range. Optical plastics lower than this range may be fluorinated polymers and may be considered, such as acry late, propionate, acetate or siloxane. These materials may be in the range of 1.3 to 1.4 for index of refraction. Again, the entirety of the distal probe tip may be formed of these types of optical plastics, but the opaque section may be metallized or coated with an opaque (e.g., a black) coating to render the housing section shown in FIG. 3 non-transmissive to light.

[0075] Referring still to FIG. 3, the light engine (e.g., the LED and its board) may be electrically connected to a battery compartment in the handle of the device. Optional control and drive electronics for driving the LED (e.g., PWM controllers, a microcontroller, current drivers, etc.) may also be located in the handle. As shown, the illumination exiting the spherical like housing at the tip directs illumination more or less orthogonally to the axis of the shaft supporting the ball like tip. In use the device tip which is spherical in nature allow s for smooth repositioning of the illumination into the eye surface by the surgeon whose view is directed through the pupil of the patient eye.

[0076] This configuration shown in FIGs. 2 and 3 and certain advantages over conventional arrangements such as fiber optics in a needle or directing illumination eye’s pupil.

[0077] First, the spherical-like shape of the housing at the tip minimizes any abrasion to the eye surface, which is always a concern since during an exam by the physician the tip will be positioned in numerous locations on the eye’s side surface.

[0078] Additionally, because the instant probe has a first material surface with a convex surface, thereby creating optical pow er, the instrument produces a tight emission beam in air, Attorney Docket: 185288.00004 i.e., when the instrument is being handled, but then produces a wider emission beam when it is pressed against the eye. This minimizes stray light and glare that might irritate the patient or the physician during the exam.

[0079] This stray light minimization feature is further enhanced by the basic configuration of the device. The device is configured with a nontransparent housing that blocks light from the LED or source contained therein from not spraying out the back and sides of the housing, where it might distract the physician. In conventional devices that include a fully transparent spherical tip. the illuminated typically produces illumination over 4 pi steradians (i.e., isotropically) and sends light towards the physician.

[0080] In contrast, in the devices described herein, the handle includes indexing features (e.g., ridges, or the very shape of the handle itself), which tell the physician the direction of light emission (i.e. to the side of the direction the long axis of the device is pointing). This allows the physician to move the probe away from the physician toward and into contact with the patient’s eye, all the time with the beam being directed laterally with respect to the physicians look axis of field of view. By providing a positive, plano-convex lens element as the emission window, the device emits a tight, easy to control beam that can be easily kept pointed to the side until the window is optically immersed in the eye. The combination of these features results in much less distraction and irritation for the physician during the exam.

[0081] In certain embodiments, further enhancements may be made to the window to further tighten the beam when the device is in air. For example, the outside surface of the window may carry one or more microlenses, or a microlens array. Each lens may be configured to tightly focus light originating at the LED (e.g., each microlens may have a focal point located at the LED, so that each lens produces a collimated beam). This would serve to produce an even tighter beam spread when the device was located in air, but the spread would again increase when the outside surfaces of the microlenses were immersed in the higher index material of the sclera. One disadvantage to this approach would be that providing microlenses on the window would render it perceptibly ‘‘rougher’’ than a smooth spherical surface, which might cause patient discomfort.

[0082] Returning still to FIG. 3, the shaft 310 that connects the handle 305 to the tip 315 is preferably of a small diameter (e.g., on the order of 1.2-2mm), and is in the range of between 30 and 50mm in length. The stiffening member 350 shown in the C and B cross sections of the Figure may comprise or include a copper or other heat dissipating element, which can be Attorney Docket: 185288.00004 included within the shaft, and which is thermally coupled to the solid-state source in the tip and runs the length of the shaft to prevent the thin-walled hollow shaft from collapsing if bent. A cross section of this heat dissipating element (“B”) shows channels for the electrical wires to run the length of the shaft to a power source.

[0083] Referring now to FIG. 4, there is shown an alternative embodiment of a scleral illuminator 400 where the shaft portion 410 of the instrument may be retractable into the handle 405. In one aspect, the shaft portion 410 may have at least two positions, a fully extended position (left), and a withdrawn position (right), in which, the shaft portion is withdrawn and occupies the handle, thereby reducing the overall length of the instrument. In other aspects, the shaft may have a third or more intermediate positions. In some embodiments, in the fully withdrawn position, the spherical-like probe tip is also withdrawn completely into the handle. In some aspects, the shaft is continuously adjustable in position such that the end of the shaft is continuously adjustable in terms of length from a distal end of the handle portion. In certain aspects, the shaft position is releasable lockable at more than one position.

[0084] In certain cases, as shown in FIG. 4, a slide button 420 is provided that is allows for user actuation. The slide button is coupled to the shaft and extends to an outside of the handle. The slide button rides in a slot 425, allowing it to be slid parallel to a long axis of the handle, and thereby to slide the shaft of the instrument into and out of the handle.

[0085] Referring now to FIG. 5, there is shown an alternative embodiment for a trans-scleral illumination probe 500 in accordance with the invention. In the embodiment of FIG. 5, ahandle 505 is provided with a battery 525, a pow er switch 520, and LED drive electronics, as described above. From the distal (upper) side of the handle extends a shaft 510, which as above is preferably thin, relatively stiff but somewhat flexible. Referring now to FIG. 5 and 7, at the interface between the handle and shaft is a gripping structure 512 that smoothly tapers on all four sides from the perimeter of the handle to the shaft. The grip section 512 may include ridges or other features to allow the user to easily and securely grip or pinch the device (e.g., between thumb and forefinger) above the handle and at the base of the shaft. This may provide for easier insertion of the probe tip of the device into the orbit, as well as provide for better control of the orientation of the device.

[0086] The grip ridges, as well as the shape of the handle, are chosen to allow the user to determine the orientation of the device when it is in the user’s hand, such that the user knows that the light emission direction is transverse and to the side of the shaft, in the direction of one Attorney Docket: 185288.00004 of the broad flat faces of the handle. In this configuration if the user is gripping the device with the user’s palm down over the thin side of the device shown on the right side of the figure, with the user’s thumb in a position to actuate the switch, the user knows that the light will be emitted to the side, away from the user’s own eyes.

[0087] In the FIG. 5 embodiment, the shaft 510 is different than the shaft described in connection with FIG. 4, in that the shaft has a rectangular rather than a circular cross section. The shaft may include a flex-like cable assembly having a stiffener member 530 which supports the distal tip / light engine and transports electrical energy to the light engine at the tip of the probe. The flex cable may include a stiff backing member 530, and an insulative top layer 535 that carries at least two (anode and cathode) conductive electrical traces for the LED drive signal.

[0088] Additionally, the probe tip 515 shown in FIG. 5 differs from the FIG. 4 tip in that it is hemispherical rather than spherical. In the FIG. 5 embodiment, the probe tip includes a hemispherical side portion 540, which itself comprises an opaque housing portion 545, and a window portion 550 having an outer surface w hich is a portion of a sphere and an inner surface with may be piano. As in FIG. 4, a light source such as an LED 555 is located behind the window' portion, and is oriented to the side to emit light in a sidew ays direction. The emission spread of this light, as in the FIG. 4 embodiment, is limited by the optical power of the planoconvex lens element that is the window, and emission of light in all other direction is blocked by the opaque housing as well as the flex circuit shaft member on which the LED is mounted.

[0089] Referring to the right hand side of FIG. 5, where the left side of the probe tip is hemispherical, the right side is flat, being provided by the flex cable, or more specifically, by the stiffener or backing member of the flex cable, which is preferably some sort of plastic. The edges and comers of this portion of the stiffener member may be broken or rounded off, but this flat side provides a blunt depressor tip which may be used like a conventional blunt depressor.

[0090] The overall shape of the probe tip shape described above is not limiting. An instrument with a flex-circuit shaft having a rectangular cross section could terminate in a probe tip having a spherical overall shape, as show n in FIG. 2-3. Additionally, the probe side (the left hand side of the right hand view of FIG. 5) need not be completely hemispherical. It could be a portion of a hemisphere, for example. Additionally, the probe side of the tip can be a short cylinder or Attorney Docket: 185288.00004 coin shape topped with a transparent window that has a surface that is a portion of a sphere. An arrangement like this is shown in FIG. 6.

[0091] While the shaft of an instrument according to the invention may be permanently attached to the handle, this is not a requirement for any of the embodiments described herein. FIG. 6 depicts an arrangement where an instrument includes a removable probe section 605 and a handle section 610. Handle section 610 includes the electrical and mechanical components described in the embodiments above, e.g., a power switch, battery, an LED driver or controller, which may be a PWM driver, other associated LED drive electronics, etc. On the distal end of the handle section 610 is a first electrical connector (e.g., a male connector), and on a proximal end of the probe section 605 is a second electrical connector 620, which is configured to be detatachly secured to the first connector 615 and to make a conductive electrical contact between conductive traces or wires coupled to first connector and conductive traces or wires coupled to the second connector. In the embodiment pictured in FIG. 6, second connector 620 is a female connector. In the simplest of cases, connectors 620 and 615 need carry only two individual connections (for the LED anode and cathode), but they may carry more. For example, connectors 620 and 615 may be any of the commonly available universal serial bus (USB) connectors, with only two conductors actually being used.

[0092] Distal probe section 605, itself includes a rigid but flexible shaft portion 625, which may be of the circular cross section type described in connection with FIGs. 2-3 or the rectangular cross section, flex circuit type described in connection with FIG. 5. The shaft portion 625 terminates, at its distal end, with an illuminated probe tip, which may be of the sort described in connection with FIG. 2-3 (having a spherical, ovoid, ellipsoid body), or a tip of the sort described in connection with FIG. 5 (having a hemispherical housing and window and a rectangular prism like back side). In the pictured embodiment, the opaque probe body is a short cylinder or coin like shape topped with a curved transparent window that is a portion of a sphere (i.e., a hemisphere or some smaller portion).

[0093] In a detachable probe arrangement as shown in FIG. 6, the distal probe portion 605 may be sterile and / or disposable, while the handle portion 610 may be reused without sterilization.

[0094] Thus far, the described embodiments locate the LED light source in the distal probe end of the device, but that is not a requirement. In alternative arrangements usable with any of the other elements described above, the LED source is located at the handle, and the light is transported to the distal probe optically, though a fiber, fiber bundle, light pipe or the like. An Attorney Docket: 185288.00004 arrangement of this sort is shown in FIG. 8. In FIG. 8 an illuminated scleral speculum 800 is shown, which as in the embodiments above, includes a handle portion 805 and a shaft portion 810, which carries a distal probe end 812. As above, the probe end 812 includes a transparent window 840 that is arranged to the side of the axis of the shaft to preferentially emit light in a sideways direction, and is otherwise configured (e.g., with a non-transparent housing 835) to block light in other directions. The window portion 840 has an outside surface that is a portion of a sphere, and may have a piano inside surface so that the element has focusing optical power relative to a point to the right of the piano surface.

[0095] The handle portion 805 includes the elements described above (i.e., a battery, switch, LED drive electronics, etc.). The handle portion also includes an LED source 815. Light emitted from the LED source 815 is coupled by a coupling lens assembly 820 to a proximal end of an optical waveguide 825, which may be a fiber, fiber bundle or light pipe. Lens assembly 820 may be a relay lens doublet comprising two nose to nose plano-convex lens, w hich images the LED chip onto the end of the waveguide. Alternatively lens assembly may be a collimating lens, e.g., a ball lens. Other lens types that are conventionally used to couple isotopic light sources into fibers may be used, such as gradient index (GRIN) coupling lenses.

[0096] As above, the instrument 800 of FIG. 8 includes a rigid but deflectable shaft 830, which may be of the sort having a circular cross section (as in FIGs. 2-3), or a flex circuit type having a rectangular cross section as in FIG. 5. The shaft may include a stiffening member (e.g., an internal stiffening member or a flexible but relatively rigid flex circuit board material). The shaft carries the w aveguide, which extends from the handle 805 to the probe tip 812. The probe tip 812 includes a steering to fold optic 845, to reflect light emitted upwardly from a distal end of the waveguide to the side, so that it will be emitted exclusively in a sideways direction through window 840.

[0097] Beam steering optic 825 may take a variety of forms. It may be a mirror (i.e., a metallized surface, preferably an aluminum or surface coated with some protective coating to prevent oxidation) inclined at 45 degrees with respect to the long axis of the shaft. In some embodiments, the mirror may be the hypotenuse surface of a right-angle prism. Steering optic ma also be a reflective interference filter optimized at the wavelength or wavelengths of the source 815. It may also be a Brewster window^ (if the polarization of the incoming light is well controlled) or a prism configured and oriented such that it steers a beam propagating in the direction of the long axis of the shaft 90 degrees through total-intemal-reflection. The optical Attorney Docket: 185288.00004 power of the window 840 may be chosen such that the window’s rear focal point is located at the distal end of the waveguide through the steering optic.

[0098] The configuration of FIG. 8 has certain advantages over embodiments where the LED is located in the probe tip. For example, the shaft portion may be made detachable, sterile and / or disposable as in FIG. 6. In such cases, the shaft portion can be disposed of and replaced without incurring the cost of another LED source, which is reused in the handle. Additionally, such an arrangement obviates a need for an electrical connector on the disposable element, which reduces cost and improves reliability’ and longevity of the device. Additionally, heat management is much easier in the optical transport arrangement of FIG. 8. Most of the heat generated by the instrument is in the vicinity of the LED source, and so located that source away from the probe tip eliminates excessive heat buildup in the probe tip, which may be unsafe or at least uncomfortable for the patient over long periods of use of the instrument.

[0099] Additionally, it will be noted that the light pipe may advantageously serve to homogenize the light being emitted from the LED source as that light is transported to the distal end of the waveguide and the probe tip. This is especially the case where the waveguide is a light pipe (e.g., a bar of acrylic or some other optical plastic having a rectangular cross section). Thus, in the case where the LED source is not a white a LED, but instead is provided as a multicolor LED (E.g., an RBG triad of LEDs), the waveguide may serve to mix light from all three colored sources, both spatially and in angle, such that what is provided at the output is a uniform, mixed light perceptible as a particular color (e.g., white, where all three color LEDs have their relative outputs controlled in the proper manner). In these embodiments, a microcontroller / LED driver may provide light of any color supportable by the three individual color chips to the probe, which may be useful for examination of certain intraocular structures or conditions.

[0100] Referring now to FIG. 9, there is shown an arrangement for providing a rechargeable scleral illuminator 900 and probe in accordance with any of the embodiments described above. The appliance includes a rechargeable battery' located in the handle 905. In one embodiment, the battery is a lithium-polymer (Li-Po) battery', or other suitable rechargeable battery. The inclusion of such a battery may necessitate a variation in the handle geometry to accommodate the battery and associated charging circuitry'. The handle 905 interfaces with charging cradle 910, which includes electronics sufficient to deliver power to the battery through some nondirect contact means such as inductive charging. The handle may be configured to be magnetically aligned to and removably coupled to the charging cradle 910. In certain Attorney Docket: 185288.00004 embodiments, the charging cradle 910 may include control electronics, including a microprocessor, to gather and report information regarding the charge state of the appliance 900 and use information (e.g., the amount of time the appliance has been removed from the cradle, the number of times the device has been removed from the cradle, the difference in pre- and post- removal charge, etc. This information may be compared to predetermined thresholds to disable the device (through it's charger) until a user performs a manual reset. This may be helpful in prompting the user to replace a replaceable shaft and probe section after a certain amount of use has been determined.

[0101] In certain embodiments, usage is tracked such that a trans-scleral illuminator designed for a limited number of procedures. The device comprises a distal probe assembly incorporating non-volatile memory for tracking usage, and a mating handle assembly. In certain embodiments, a charging station is also provided, the station including authentication and control circuitry configured to disable the probe once a predetermined number of uses or a specified time interval has been exceeded.

[0102] Limiting the number of permissible uses is justified by considerations of sterility, material integrity, and optical and electrical performance. Repeated exposure to cleaning agents and disinfection cycles can degrade plastics, polymers, adhesives, coatings, and optical components, leading to reduced safety and diminished light output or battery capacity. Accordingly, the materials selected for the trans-scleral illuminator are chosen for biocompatibility, patient safety, and resistance to microbial contamination while maintaining performance over a validated number of uses.

[0103] The instrument is intended for use in office-based or minor procedure settings where high-temperature autoclave sterilization is not employed. The probe and handle materials are thus selected to withstand low-temperature or chemical disinfection methods, such as immersion in sterilization trays containing liquid sterilants or exposure to vapor-phase disinfectants. These reprocessing methods allow for safe, limited reuse of the device while avoiding the material or electronic degradation that may occur under autoclave conditions.

[0104] The illuminator is validated for a maximum of N uses, beyond which sterility and functional performance cannot be ensured. The probe incorporates mechanical, electrical, or firmware-based interlocks that prevent further activation after the maximum number of validated cycles has been reached, thereby ensuring patient safety and compliance with labeling. Attorney Docket: 185288.00004

[0105] In certain embodiments, the device may include usage indicators, such as LEDs or small visual displays located on the probe, handle, or charging station, configured to provide information including use count, status, readiness, or fault conditions.

[0106] In one embodiment, a medical probe assembly comprises a reusable handle unit and a disposable probe element configured for limited reuse. The probe element includes a flexible circuit substrate having a plurality of conductive contact pads disposed along an insertion edge. The handle unit includes a corresponding array of spring-loaded electrical contact pins, such as pogo pins, positioned within an insertion receptacle. Upon insertion of the probe element into the receptacle, the contact pins engage the conductive pads to establish electrical communication between circuitry on the probe element and control electronics housed within the handle unit.

[0107] The control electronics may include a microcontroller coupled to non-volatile memory configured to store usage-related data. The system is adapted to detect insertion and removal events of the probe element by monitoring the electrical continuity state of one or more designated detection or counter pins. When the probe is withdrawn, the interruption of continuity generates a hardware interrupt or is detected through a polling routine, thereby causing the microcontroller to increment a usage counter stored in memory. The logic ensures that the counter increments only upon physical separation and reinsertion of the probe element, and not merely through power cycling of the handle unit, thereby providing an accurate record of actual use cycles.

[0108] In certain embodiments, the probe element itself includes an identification or authentication circuit, such as an EEPROM or one-wire memory device, configured to store unique device identifiers and usage data. In such cases, the use count may be updated within the probe circuit and communicated to the handle unit or an associated charging or docking station upon electrical connection.

[0109] When the recorded use count reaches a predetermined threshold value (for example, ten insertion cycles), the control electronics are configured to disable one or more functional circuits of the probe assembly. Such circuits may include, for example, illumination drivers, sensor interfaces, or signal-processing pathways, thereby preventing further operation beyond validated limits. In some embodiments, the system provides a warning indication — visual (e.g., via LED indicators or display), audible, or haptic — to alert the operator when the usage limit is being approached or has been reached. Attorney Docket: 185288.00004

[0110] A number of different possible design configurations are available to allow the device to track usage, or become inoperable after a certain amount of usage.

[0111] Fuse-Link Flex Circuit Counter

[0112] In one embodiment, the flexible circuit substrate of the probe element incorporates a series of sacrificial conductive traces configured as fuse links. These traces are arranged in a sequential array, with each trace corresponding to one permitted use cycles, the number of on / off cycles and time duration is recorded. The traces may be formed with reduced cross- sectional area relative to other conductors on the flex circuit, making them susceptible to controlled destruction.

[0113] During or immediately after each removal event, the handle electronics deliberately route a cunent pulse of sufficient magnitude through the next sequential fuse link to cause its destruction by resistive heating (i.e., ‘’blowing” the fuse). This cunent may be delivered through dedicated counter pins separate from the functional signal pins. The progression through the fuse array creates a permanent, tamper-evident record of usage.

[0114] The handle electronics monitor the continuity of the remaining fuse links in the limited use handle. Once all fuse links in the series have been destroyed (e.g., after 10 uses), no complete electrical pathway remains between designated counter pins, and the handle interprets this condition as exhaustion of the permitted usage count. The probe and handle are thereafter rendered non-functional, as the absence of a complete counter circuit prevents activation of the probe’s operational systems.

[0115] This embodiment provides a hardware-based counter that cannot be reset by software manipulation or power cycling, thereby ensuring compliance with single-use or limited-use regulatory requirements.

[0116] Electronic Memory-Based Authentication

[0117] In a further embodiment, the probe element includes an integrated circuit memory device mounted on or integrated within the flexible circuit substrate. The memory device may comprise an EEPROM, OTP (one-time programmable) memory, or similar non-volatile storage accessible via a serial communication protocol such as I2C, SPI, or 1-Wire.

[0118] Upon each insertion, the handle electronics initiate a cryptographic handshake or authentication sequence with the memory device. This handshake may include reading a unique identifier, verifying a digital signature, and retrieving the current usage count stored in the Attorney Docket: 185288.00004 memory'. After successful authentication and functional use, the handle commands the memory device to increment its internal usage counter. The memory device may be configured such that the counter increment is irreversible and persists even if power is removed.

[0119] Before enabling probe functionality, the handle verifies that the usage count has not exceeded the permitted threshold. If the count is exhausted, or if the authentication handshake fails (indicating a counterfeit or incompatible probe), the handle refuses to activate energy delivery', sensing, or other operational functions.

[0120] In some variations, the memory' device also stores calibration data, manufacturing information, expiration dates, or patient-specific usage logs. The mandatory electronic handshake creates a hardware-enforced pairing between the handle and authorized probe elements, preventing use of unauthorized, expired, or exhausted probes.

[0121] Mechanical Trace Destruction Upon Withdrawal

[0122] In one embodiment, the probe element is designed such that removal from the handle irreversibly damages critical conductive pathways, rendering the probe permanently nonfunctional. The flexible circuit substrate includes one or more retention features, such as barbs, tabs, or crimp zones, that engage with corresponding features in the handle's insertion receptacle.

[0123] These retention features are positioned such that, during withdrawal of the probe, they exert lateral or shear forces on the flexible substrate. Conductive traces on the flex circuit are routed through or adjacent to these mechanically stressed regions. The withdrawal action causes the retention features to tear, shear, or fracture the traces, creating permanent open circuits.

[0124] In some implementations, the traces are deliberately thinned or perforated in the stress zones to promote predictable failure. Even partial withdrawal — insufficient to fully remove the probe but enough to initiate tearing — results in irreparable damage. Upon any subsequent reinsertion attempt, the handle electronics detect the absence of electrical continuity on one or more critical signal paths and refuse to activate the probe.

[0125] This embodiment provides a tamper-evident, hardware-enforced single-use mechanism that does not rely on electronic counters or software controls, thereby eliminating opportunities for circumvention through reprogramming or power manipulation.

[0126] Disposable Electrical Key with Physical Break Attorney Docket: 185288.00004

[0127] In another embodiment, the probe element incorporates a disposable electrical “key” structure comprising a conductive bridge or shorting element connecting two or more designated contact pads on the flexible circuit or board. This bridge may be a thin foil trace, a conductive adhesive strip, or a separate jumper component.

[0128] Upon first insertion, the handle electronics detect the presence of the intact bridge by measuring continuity or a characteristic impedance between the key pins. This detection serves as authentication that the probe is new and unused. During the insertion process or during initial functional use, mechanical forces or controlled electrical stress (e.g., electro-migration, fusing) destroy the bridge.

[0129] When the probe is removed, the severed bridge cannot restore electrical continuity. Upon any reinsertion attempt, the handle detects the open circuit where the bridge formerly existed and interprets this as evidence of prior use, thereby refusing to enable probe functionality.

[0130] Variations include multiple redundant bridges for enhanced reliability', or bridges configured to break only upon reaching full insertion depth, ensuring that incomplete insertion attempts do not inadvertently consume the single-use key.

[0131] Pin-Shearing and Pad Destruction Mechanism

[0132] In a further embodiment, the handle’s contact pins are configured with geometries or surface treatments designed to permanently damage the corresponding contact pads on the probe’s flexible circuit upon withdrawal. For example, the contact pins may have knife-edge profiles, abrasive coatings, or sharp comers that score or abrade the conductive pads during sliding contact.

[0133] On first insertion, the pins make electrical contact with intact pads, enabling normal probe function. Upon withdrawal, the pins scrape through the pad material, removing conductive layers or creating deep scratches that interrupt the conductive pathways. The damage may be localized to critical pads designated for authentication or signal transmission.

[0134] On any subsequent reinsertion, the damaged pads fail to establish reliable electrical contact. The handle electronics detect abnormal impedance, intermittent connectivity, or complete open circuits on the affected channels and disable probe operation. Attorney Docket: 185288.00004

[0135] In some implementations, the pins are spring-loaded with sufficient force to ensure consistent pad destruction, and the pad material (e.g., gold, copper, or carbon) is selected to deform or delaminate predictably under the shearing forces.

[0136] Tear Zone with Embedded Conductors

[0137] In another embodiment, the flexible circuit substrate includes one or more preweakened zones designed to tear or fracture when the probe is withdrawn. These tear zones may be created by laser scoring, die-cutting, perforations, or selective thinning of the substrate material.

[0138] Critical conductive traces are routed through these tear zones. The zones are aligned with the handle’s insertion slot such that the bending and tensile forces during withdrawal concentrate stress on the weakened areas, causing controlled fracture. The fracture propagates through the embedded traces, creating permanent open circuits.

[0139] The tear zones may be configured with directional bias, ensuring that normal flexure during intended use does not trigger premature failure, but withdrawal motion reliably causes tearing. In some variations, multiple redundant tear zones are provided, ensuring that even if one zone fails to fracture completely, others will interrupt critical pathways.

[0140] Upon reinsertion, the handle detects the broken traces through continuity testing or impedance measurements and prevents probe activation.

[0141] Break-Before-Make Sacrificial Element

[0142] In yet another embodiment, the probe element includes a sacrificial conductive element positioned such that achieving full insertion depth consumes or destroys the element. This element may be a thin foil fuse, a conductive polymer film, or a plated trace with a controlled failure point.

[0143] The element bridges two contact points required for probe authentication or functional operation. Prior to insertion, the element is intact, and its continuity can be verified. As the probe is inserted, mechanical forces (e.g., compression, shearing) or electrical stress (e.g., programmed current pulse) destroy the element. This destruction occurs once the probe reaches its fully seated position, at which point the element is no longer needed for initial authentication. Attorney Docket: 185288.00004

[0144] Upon withdrawal and any subsequent reinsertion attempt, the absence of the sacrificial element is detected by the handle electronics as an open circuit condition. Since the element cannot be restored, the probe is permanently disabled after the first use cycle.

[0145] This “break-before-make” approach ensures that the probe functions normally during its intended single or limited use cycle but becomes inoperable thereafter, providing hardware- enforced limited-use functionality.

[0146] Referring now to FIG. 10, there is shown an alternative embodiment of a trans-scleral illuminator for use with a three mirror contact lens, also called a Goldman three-mirror contact lens.. A three-mirror contact lens 1005 is a known piece of ophthalmic examination equipment. The device 1005 includes a contact lens 1007 that is configured to be placed in contact with the patient’s cornea (i.e., the outermost powered surface of the eye 1025). The device 1005 may include an optical element that contacts the cornea and is designed to minimize the optical power of the cornea. The device 1005 also has a hollow barrel 1008 having a decreasing circular cross section toward a distal direction along a distal portion of its length. Distributed circumferentially around the interior of the barrel are a plurality of inclined mirrors 1009 that enable an examining physician to view different off-axis portions of the patient’s retina. In one embodiment, a trans-scleral illuminator 1010 is provided as an auxiliary contact lens holder. Holder 1010 is generally shaped as an annulus, and accepts within its circular interior and secures a three mirror contact lens 1005, via a snap fit or the like. Holder 1010 is free to rotate with respect to the lens 1005 and vice versal. Holder 1010 includes a rigid yet flexible shaft 1015 coupled to a probe tip 1020, of the sort of probe tips described above (e.g., a hemispherical probe tip. The probe tip, as discussed above, is configured to contact the side of the eye, as shown, and emit light that is confined to a laterally projecting beam angle. Preferably, the shaft 1015 extends in a distal direction (i.e., away from the examiner), but also laterally, to allow for it to be positioned on a side surface of the eye while the contact lens remains centered on the cornea. The holder 1010 preferably includes a battery , charging port 1030, a switch 1040. and LED drive electronics as discussed above. The shaft 1015 may be a flex circuit shaft that includes a stiffener and conductive traces as discussed above.

[0147] It should be understood that, unless explicitly stated or otherwise required, the features disclosed in embodiments explicitly described herein and elsewhere in this disclosure may be used in any suitable combinations. Other embodiments and uses of the above inventions will be apparent to those having ordinary' skill in the art upon consideration of the specification and practice of the invention disclosed herein. It should be understood Attorney Docket: 185288.00004 that features listed and described in one embodiment may be used in other embodiments unless specifically stated otherwise. The specification and examples given should be considered exemplary only, and it is contemplated that the appended claims will cover any other such embodiments or modifications as fall within the true scope of the invention.

Claims

Attorney Docket: 185288.00004CLAIMSThe invention claimed is:

1. A trans-scleral illuminator and depressor comprising: a handle; a shaft beginning at a distal end of the handle and extending in a distal direction, the shaft defining a central axis; a probe tip at a distal end of the shaft on the central axis, the probe tip having a smooth and rounded outer surface, the probe tip comprising an opaque housing and a transparent window located laterally on the probe tip with respect to the central axis; a light engine located within the probe tip, comprising an LED arranged within the probe tip and arranged with an exposed surface of an LED chip facing the window to emit light laterally through the transparent window, wherein the LED, window and opaque housing are arranged such that light emitted from the LED from the probe tip is confined to a beam having a central propagation direction oriented perpendicularly with respect to the central axis, and a beam angle about the central propagation direction of less than 180 degrees in air.

2. The illuminator of claim 1, wherein the probe time has an outer surface that includes a spherical shape.

3. The illuminator of claim 2, wherein both the opaque housing and the transparent window have outer spherical surfaces of the same radius, where both radii are located at the same position.Attorney Docket: 185288.000044. The illuminator of claim 1, wherein the transparent window section comprises an outer spherical surface and an inner piano surface facing the LED..

5. The illuminator of claim 4, wherein the transparent window section includes an optically transparent material having an index of refraction between 1.4 and 1.8.

6. The illuminator of claim 1, wherein the shaft has a circular cross section along at least some portion of its length.

7. The illuminator of claim 6, wherein the shaft comprises at least two electrically conductive pathways for electrical current and a rigid but flexible stiffener.

8. The illuminator of claim 7, wherein the rigid but flexible stiffener runs coaxially through the shaft, along the central axis.

9. The illuminator of claim 1 , wherein the shaft has a rectangular cross section along at leas a portion of its length.

10. The illuminator of claim 1, wherein the handle includes a battery, a switch and electronics sufficient to drive the LED.

11. The illuminator of claim 10, wherein the shaft is detachable from the handle, and wherein the shaft and the handle comprise electrical connectors.Attorney Docket: 185288.0000412. The illuminator of claim 1, wherein the transparent window as a spherical outer surface of radius R1 and comprises a material having an index of refraction of Nl, and wherein N1 and R1 are selected according to the following parameters:O.5*|R1|<N1<4*|R1|;Nl ^1.45.

13. A trans-scleral illuminator and depressor comprising: a handle; a shaft beginning at a distal end of the handle and extending in a distal direction, the shaft defining a central axis; a probe tip at a distal end of the shaft on the central axis, the probe tip having a smooth and rounded outer surface, the probe tip comprising an opaque housing and a transparent window located laterally on the probe tip with respect to the central axis; a light engine located within the handle, the light engine including an LED optically coupled to a proximal end of a waveguide, the waveguide that extending along the shaft parallel to the central axis to a distal end located in the probe tip; wherein the probe tip comprises a beam steering optic optically coupled to the distal end of the waveguide and being configured to redirect light emitted from the distal end of the waveguide, laterally, through the transparent window such that light emitted from the probe tip is confined to a beam having a central propagation direction oriented perpendicularly with respect to the central axis, and a beam angle about the central propagation direction of less than 180 degrees in air.

14. The illuminator of claim 13, wherein the w aveguide is one of an optical fiber, fiber bundle or light pipe.Attorney Docket: 185288.0000415. The illuminator of claim 13, wherein the beam steering optic comprises a mirror.

16. The illuminator of claim 15, wherein the mirror is arranged on the hypotenuse surface of a right angle prism.

17. The illuminator of claim 1, wherein the transparent window includes an outer spherical surface and a piano interior surface facing the been steering optic.

18. An ophthalmic assembly, comprising: a three-mirror contact lens having a central mechanical axis that extends through a center of a patient’s cornea when in use; a trans-scleral illuminator having a generally annular shape configured to receive and detachably secure the three-mirror contact lens and be arranged circumferentially around the three-mirror contact lens; wherein the trans-scleral illuminator comprises a flexible shaft extending in a distal direction, toward the patient when in use, and also in a laterally offset direction, the shaft having a distal end terminating in a probe tip having an LED, a transparent window having a partially spherical shape, and an opaque housing; wherein the wherein the LED, window and opaque housing are arranged such that light emitted from the LED from the probe tip is confined to a beam having a central propagation direction oriented perpendicularly with respect to the central mechanical axis, and a beam angle about the central propagation direction of less than 180 degrees in air.

19. The assembly of claim 18, wherein the opaque housing has a partially spherical shape.Attorney Docket: 185288.0000420. The assembly of claim 19, wherein the probe tip has a hemispherical shape.

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