Apparatus and method for performing videonystagmography and oculometry

Abstract

An oculometry apparatus including an interference device, an infrared (IR) light source to emit IR to irradiate a patient eye, an imaging device to measure IR light reflected by the patient eye, and a controller operable to control the operation of each of the interference device, the infrared light source, and the imaging device. The controller can further operate the interference device to occlude optical stimuli to selectively permit or prevent optical stimuli from being perceptible by the patient eye. The controller can operate the IR source to illuminate the patient eye with infrared light and operate the imaging device to produce an image of the patient eye from the reflected IR light from the patient eye.

Description

APPARATUS AND METHOD FOR PERFORMING VIDEONYSTAGMOGRAPHY AND OCULOMETRYField of the Invention

[0001] The present invention relates to systems and methods for performing videonystagmography (VNG) and oculometry.Brief Description of the Drawings

[0002] FIG. 1 is a schematic view of a VNG system according to an embodiment of the invention.

[0003] FIG. 2 is a perspective view of a goggle device comprising a VNG apparatus according to an embodiment of the invention.

[0004] FIG. 3 is a schematic view of a VNG system according to an embodiment of the invention.

[0005] FIG. 4 is a perspective view of a goggle device comprising a VNG apparatus according to an embodiment of the invention.

[0006] FIG. 5 is a schematic representation of a VNG system according to an embodiment of the invention.

[0007] FIG. 6 is a flowchart illustrating a method of performing a VNG evaluation according to an embodiment of the invention.Detailed Description of the Invention

[0008] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Those of ordinary skill in the art realize that the following descriptions of the embodiments of the present invention are illustrative and are not intended to be limiting in any way. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Like numbers refer to like elements throughout.

[0009] Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the invention.

[0010] In this detailed description of the present invention, a person skilled in the art should note that directional terms, such as “above,” “below,” “upper,” “lower,” and other like terms are used for the convenience of the reader in reference to the drawings. Also, a person skilled in the art should notice this description may contain other terminology to convey position, orientation, and direction without departing from the principles of the present invention.

[0011] Furthermore, in this detailed description, a person skilled in the art should note that quantitative qualifying terms such as “generally,” “substantially,” “mostly,” and other terms are used, in general, to mean that the referred to object, characteristic, or quality constitutes a majority of the subject of the reference. The meaning of any of these terms is dependent upon the context within which it is used, and the meaning may be expressly modified.

[0012] An embodiment of the invention, as shown and described by the various figures and accompanying text, provides a VNG system 100. The VNG system 100 may comprise an illumination light source 102, a display projection apparatus 110, an interference apparatus 130, and an imaging device 170. The illumination light source 102 may be operable to emit electromagnetic radiation (EMR) within an imaging spectrum. In the present embodiment, the imaging spectrum may include infrared (IR) light (EMR having a wavelength within a range from 700 nm to 1 millimeter (mm)).

[0013] The display projection apparatus 110 may comprise a display device 112 and an optical projector 114. The display device 112 may be operable to project an image along a display path 116. Images displayed by the display device 112 may be configured to enable a VNG evaluation of a patient. The optical projector 114 may be configured to reflect, refract, or otherwise manipulate the propagation of light emitted by the display device 112 along the display path 116. Light emanating from the optical projector 114 may be incident upon a screen 1 18, defining an end of the display path 1 16. The screen 118 may be any type of screen operable to reflect light incident thereupon to be viewable by an observer. In some embodiments, the screen 118 may be a retroreflective screen, i.e. configured to reflect light incident thereupon mostly in the same direction from which it was incident.

[0014] The interference apparatus 130 may be positioned along a viewing path 140. The viewing path 140 may be understood as a path between the screen 118 and a patient eye 150 of the patient, such that light reflected by the screen 118 may be perceived by the patient eye 150. The interference apparatus 130 may comprise a hot mirror 132, namely, a structure operable to permit visible light (EMR having a wavelength within a range from 400 nanometers (nm) to 700 nm) to pass therethrough, while reflecting IR. The hot mirror 132 may be positioned such that light reflected from the screen 118 in the direction of the patient eye 150 may pass therethrough along the viewing path 140. Moreover, the hot mirror 132 may be positioned such that infrared light emitted by the illumination light source 102 is reflected thereby in the direction of the patient eye 150.

[0015] The interference apparatus 130 may further comprise an interference device 134. The interference device 134 may be operable to at least partially occlude light along the viewing path 140. Moreover, the interference device 134 may be operable to selectively occlude light along the viewing path 140.

[0016] The interference device 134 may be configured to transition between a first configuration having a first relative optical characteristic and a second configuration having a second optical characteristic. Each of the first and second optical characteristics may affect light within the visible spectrum. The first relative optical characteristic may be configured to permit discernible optical stimuli to be perceived by the patient eye 150, more specifically, by a retina of the patient eye 150. The second relative optical characteristic may be configured to prevent discernible optical stimuli from being perceived by the patient eye 150, more specifically, by the retina of the patient eye 150. In some embodiments, the first and second optical characteristics may be first and second transmittances of light within the visible spectrum, respectively. The first relative transmittance may be greater than or equal to 20%, and the second relative transmittance may be less than or equal to 5%. Additionally, in some embodiments, the interference device may be configured to have a transmittance of light within an IR spectrum having a peak wavelength within a range from 975 nm to 985 nm that is greater than or equal to 25%.

[0017] In another embodiment, the first and second optical characteristics may be scattering behaviors. In such embodiments, the scattering behavior of the second relative optical characteristic may be such that light is scattered to a greater magnitude than when the interference device 134 is in the first relative optical characteristic, such that an image or other optical stimulus projected onto the screen 118 is discernible by the patient eye150 when the interference device is in the first configuration and not discernible by the patient eye 150 when the interference device 134 is in the second configuration.

[0018] The interference device 134 may be any device operable to transition between first and second configurations as described above. Such devices include, but are not limited to, liquid crystal devices, electrochromic devices, polymer dispersed liquid crystal (PDLC) devices, polymer network liquid crystal (PNLC) devices, smart films, smart glasses, switchable privacy smart films, switchable privacy smart glasses, and the like. In some embodiments, the interference device 134 may comprise two devices, for example, a PDLC device and an electrochromic device. All possible combinations of devices are contemplated and included within the scope of the invention. Moreover, where multiple devices are included, the devices may be independently switchable between respective first and second configurations. In some embodiments, the multiple devices may be collectively switchable between first and second configurations.

[0019] As mentioned above, the illumination light source 102 may be configured to emit imaging EMR, namely, IR light, in the direction of the hot mirror 132 to be reflected thereby and incident upon the patient eye 150. The illumination light source 102 may be any type of IR light-emitting device as is known in the art, including, but not limited to, light-emitting semiconductor devices, including light-emitting diodes (LEDs), organic LEDs, quantum dot devices, and the like. In some embodiments, the illumination light source 102 may emit IR light having a peak wavelength at 940 nm, or 940 nm ± 5 nm, or 940 nm ± 10 nm. In some embodiments, the illumination light source 102 may have an emitting profile in the configuration of a half cone 0 having an angle within a range of ± 10 degrees to ± 30 degrees. The half cone angle 0 may be selected to correspond to an illumination area with a diameter d given by the equation d = distance(mm) * 2 * tan(0) where the distance(mm) is a distance from the illumination light source 102 to the patient eye 150 along an illumination path 160. A commonly accepted value for d to completely irradiate the patient eye 150 with a sufficiently uniform illumination distribution is 30 mm. In one embodiment, d equals 30 mm and where the distance(mm) is 87 mm, 0 may equal 10°.

[0020] IR light reflected from the patient eye 150 may travel along an imaging path 162. The imaging path 162 may be incident upon the interference apparatus 130 and reflected by the hot mirror 132. After being reflected, reflected IR light travelling along the imaging path 162 may enter the imaging device 170.

[0021] The imaging device 170 may be configured to generate an image and / or video of a representation of the patient eye 150 based upon the reflected IR light traveling along the imaging path 162. The imaging device 170 may comprise a housing 172, and an image sensor 174. The housing 172 may have an opening 173 at an end thereof and an internal cavity 175. The image sensor 174 may be positioned within the internal cavity 175 of the housing 172 such that it is operable to sense EMR, particularly IR, entering the internal cavity 175 from the opening 173. The image sensor 174 may be operable to generate one or both of still images of the patient eye 150 and a video recording / stream of the patient eye 150. In some embodiments, live imaging and / or video streams may be generated by the image sensor 174.

[0022] The imaging device 170 may further comprise one or more optics. In the present embodiment, the imaging device comprises a first optic 176 positioned at or adjacent to the opening 173. The first optic 176 may refract EMR passing therethrough and also protect the internal cavity 175 from intrusions from the environment surrounding the VNG system 100. In some embodiments, the first optic 176 may be a variable focus optic that is manipulable by one or both of a user or an autofocus device (not shown) operable to adjust the focus of the first optic 176 to a desired focusing setting. The imaging device 170 may further comprise a second optic 178. The second optic 178 may be positioned within the internal cavity and / or optically behind or in front of the first optic 176 along the imaging path 162. The second optic 178 may be a fixed focus optic / lens. The combined focusing of IR light along the imaging path 162 may focus the IR light to be optimally measurable by the image sensor 174.

[0023] The VNG system 100 may further comprise one or more polarizers configured to polarize the IR light in the system 100. In the present embodiment, the VNG system 100 may comprise a first polarizer 182 and a second polarized 84. The first polarizer 182 may be positioned along the illumination path 160 such that it polarizes IR light emitted by the illumination light source 102 in a first polarizing orientation prior to irradiating the patient eye 150. In the present embodiment, the first polarizer may be positioned optically between the illumination light source 102 and the hot mirror 132. The second polarizer 184 may be positioned along the imaging path 162 such that it polarizes IR light reflected by the patient eye 150 in a second polarizing orientation before being incident upon the image sensor 174. The second polarizing orientation may be different from the first polarizing orientation, such that the second polarizer 184 cross-polarizes IR light with the first polarizer 182. In the present embodiment, the second polarizer 184 may be positioned optically between the hot mirror 132 and the imaging device 170.

[0024] Referring now to FIG. 2, a goggle device 200 comprising a portion of the VNG system 100 is presented. Specifically, the goggle device 200 comprises the illumination light source 102, the interference apparatus 130, and the imaging device 170. Further, the goggle device 200 comprises two sets of illumination light sources 102, interference apparatuses 130 and imaging devices 170, one for each eye of a patient wearing the goggle device 200.

[0025] Referring now to FIG. 3, an embodiment of an oculometry apparatus 300 according to an embodiment of the invention is presented. The oculometry apparatus 300 may comprise an illumination light source 302 similar to the illumination light source 102 of the VNG system 100 for FIG. 1 . The oculometry apparatus 300 may further comprise an interference apparatus 330 comprising a transparent structure 332 and an interference device 334, the interference device 334 being similar to the interference device 134 of FIG. 1. The transparent structure 332 may be formed of material that is generally transparent to visible light. In contrast to the hot mirror 132 of FIG. 1 , it is not necessary for the transparent structure 332 to reflect IR light. In some embodiments, the transparent structure 332 may absorb IR light. Such absorption may be accomplished by forming the transparent structure 332 of a material that is generally transparent to visible light but absorbent to IR light or by attaching or applying a coating of material that is transparent to visible light and absorbent to IR light to a surface of the transparent structure 332. The transparent structure 332 may also have optical refraction properties as a spectacle lens to correct the refractive errors of a patient eye. As described above, the interference device 334 may be positioned on one side of the transparent structure 332 and operable to transition between first and second configurations to selectively occlude visible light passing therethrough to permit or prevent optical stimuli being projected or displayed onto a screen 318 from traveling along a viewing path 340 to form an image on a retina of the patient eye 350.

[0026] In the present embodiment, the illumination light source 302 may be positioned adjacent to the transparent structure 332 and positioned to emit IR light along an illumination path 360 in the direction of the patient eye 350 without needing to be reflected. Additionally, the illumination light source 302 may emit light in an illumination field 361 that encompasses the patient eye 350.

[0027] The imaging sensor 374 may similarly be positioned adjacent to the transparent structure 332. The imaging sensor 374 may be positioned to sense IR light reflected by the patient eye 350 along an imaging path 362. Moreover, the imaging sensor 374 may be positioned outside the illumination field 361 . This may prevent non-reflectedI R light, i.e. I R light that is not reflected by the patient eye 350, emitted by the illumination light source 302 from being directly sensed by the imaging sensor 374. In some embodiments, where the illumination light source 302 is positioned on a first end of the transparent structure 332, for example, a lower end, the imaging sensor 374 may be positioned on a second end of the transparent structure 332, for example, an upper end.

[0028] The oculometry apparatus 300 may further comprise first and second polarizers 382, 384 configured to polarize IR light in first and second polarizing orientations, respectively, to cross-polarize the reflected IR light being sensed by the imaging sensor 374 and being respectively positioned along the illumination path 360 and the imaging path 362.

[0029] Referring now to FIG. 4, a goggle device 400 comprising the oculometry apparatus 300 of FIG. 3 is presented. The goggle device 400 comprises first and second interference apparatuses 430’, 430” structured as the interference apparatus 330 of FIG. 3. Furthermore, the goggle device 400 comprises a first and second pluralities of illumination light sources 402’, 402” positioned adjacent the first and second interference apparatuses 430’, 430” respectively. The individual light sources of the first and second pluralities of illumination light sources 402’, 402” may be supported by a frame 401 of the goggle device 400 and extend away from the frame 401 into an area adjacent the interference apparatuses 430’, 430”, which may also be supported by the frame 401. Such placement may facilitate complete or near-complete irradiation of the patient eye, particularly, the iris of the patient eye, reducing interference caused by the eyelashes, eyelids, sclera or other eye structures of the patient.

[0030] The goggle device 400 may further comprise conductive structures 436 extending from the frame 401 to the light sources of the pluralities of illumination light sources 430’, 430”. The light sources of the pluralities of illumination light sources 402’, 402” may be supported by one of the conductive structures 436 or adhered to and supported by the interference apparatuses 430’, 430”. The plurality of illumination light sources 402’, 402” may be energized and caused to emit IR light by electricity conducted along the conductive structures 436.

[0031] The light sources of the pluralities of illumination light sources 402’, 402” may be positioned adjacent the interference apparatuses 430’, 430” so as to more uniformly irradiate the patient eye. In the present embodiment, one of the light sources of each of the pluralities of illumination light sources 402’, 402” is positioned near an upper end of the interference apparatuses 430’, 430” and two of the light sources of the pluralities of illumination light sources 402’, 402” are positioned adjacent to a lower endof the interference apparatuses 430’, 430”. Such distribution may facilitate the complete or near-complete irradiation of the patient eye as mentioned above. In the present embodiment, the light sources are further distributed across a length of the interference apparatuses 430’, 430”. Such distribution may also facilitate the complete or nearcomplete irradiation of the patient eye as mentioned above. In some embodiments, the light sources of the pluralities of illumination light sources 402’, 402” may be positioned such that their illumination fields 461’, 461” overlap with those of the other light sources adjacent the same interference apparatus 430’, 430”. Such overlapping of illumination fields 461’, 461” may facilitate complete or near-complete irradiation of the patient eye.

[0032] The goggle device 400 further comprises first and second pluralities of imaging sensors 474’, 474”. The pluralities of imaging sensors 474’, 474” may be positioned to sense and measure IR light reflected from the patient eyes. More specifically, light emitted by the first and second pluralities of illumination light source 402’, 402” and reflected by the patient eyes may be measured by the first and second pluralities of imaging sensors 474’, 474”. The first and second pluralities of imaging sensors 474’, 474” may be distributed along the lengths of the upper and lower ends of the interference apparatuses 430’ 430”, in some embodiments similar to the distribution of the first and second pluralities of illumination light sources 402’, 402” with a first imaging sensor of the pluralities of imaging sensors 474’, 474” being positioned near the middle along the length of the lower end of the interference apparatuses 430’, 430” and second and third imaging sensors of the pluralities of imaging sensors 474’, 474” being positioned proximate to opposing ends of the length of the upper end of the interference apparatuses 430’, 430”. Moreover, the first and second pluralities of imaging sensors 474’, 474” may be positioned so as to be generally interspersed with the first and second pluralities of illumination light sources 402’, 402”. Such interspersing may facilitate complete illumination and imaging of the patient eyes. Moreover, the pluralities of imaging sensors 474’, 474” may be positioned such that fields of view thereof (not shown) do not permit IR light emitted from the pluralities of illumination light sources 402’, 402” may be sensed directly by the imaging sensors, but instead only measure IR light emitted by the light sources and reflected by the patient eyes. Additionally, the pluralities of imaging sensors 474’, 474” may be positioned at the ends of conductive structures 436 to facilitate imaging of the patient eyes without obstruction of other anatomical features.

[0033] Referring now to FIG. 5, a VNG system 500 according to an embodiment of the invention is presented. The VNG system 500 may comprise a controller 502, an IR light source 504, an interference device 506, and an imaging device 508. Each of the IRlight source 504, the imaging device 508, and the interference device 506 may be any of the similarly named structures as described in the prior embodiments. The controller 502 may be any processing device known in the art operable to control the operation of the IR light source 504, the interference device 506, and the imaging device 508, including, but not limited to integrated circuits, microprocessors, field programmable gate arrays, and the like. The controller 502 may be operable to perform all the functions described hereinabove. The system 500 may further comprise a memory device 514 positioned in operable communication with the controller 502. The memory device 514 may be any non-transitory computer-readable device known in the art that may have software stored thereon, including, but not limited to, hard disk drives, solid state drives, flash memory devices, and the like. Software stored on the memory device 514 may be configured to cause the controller 502 to perform the operations described above.

[0034] The VNG system 500 may further comprise a communication device 512. The communication device 512 may be positioned in operable communication with the controller 502 and may be operable to communicate with a remote computerized device 516 either directly or across a network, including personal area networks, local area networks, and wide area networks, including the network. Example of such devices include universal serial bus (USB) device controllers, serial ports, Ethernet devices, 8O2.xx devices such as Wi-Fi, Bluetooth, Zigbee, Z-wave, and Matter devices, cellular devices including 3G, 4G, and 5G devices, and any other wired or wireless communication device conforming to any standard as is known in the art. The communication device 512 may be operable to communicate with a remote computerized device 516 to send and receive data and / or commands, including, but not limited to commands to initiate a VNG evaluation, parameters of performing a VNG evaluation, results of performing a VNG evaluation, and images of patient eyes measured by the imaging device 508.

[0035] In some embodiments, a display apparatus 518 similar to the display apparatus 110 of FIG. 1 may be operated by the controller 502. In other embodiments, the display apparatus 518 may be operated by the remote computerized device 516. In such embodiments, the controller 502 may be configured to synchronize its operation with the remote computerized device 516.

[0036] Fig. 6 is a flowchart of an example process 600. In some implementations, one or more process blocks of Fig. 6 may be performed by a VNG device according to the embodiments of the invention.

[0037] As shown in Fig. 6, process 600 may include positioning a patient eye such that it can observe optical stimuli along a viewing path (block 602). For example, a patient’s eye may be positioned within a VNG device such that it can observe optical stimuli along a viewing path, as described above. As also shown in Fig. 6, process 600 may include emitting infrared light from an infrared light source along an illumination path of a patient eye (block 604). As further shown in Fig. 6, process 600 may include selectively operating an interference device between a first configuration with a first relative optical characteristic and a second configuration with a second relative optical characteristic (block 606). Such optical characteristics include transmissivity and scattering profiles, as described above. As also shown in Fig. 6, process 600 may include generating a video measurement of the patient eye by measuring infrared light reflected from the patient eye along an imaging path with an imaging device (block 608). Such video measurement may be generated by image sensors as described in the embodiments of FIGS. 1-4

[0038] Process 600 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in connection with one or more other processes described elsewhere herein. In a first implementation, the oculometry method may further include making a corneal mark on a cornea of the patient eye at a reference location with an infrared corneal marker (block 610). Process 600 may further comprise identifying a reference location of the corneal mark by capturing a reference image of the corneal mark during a calibration process (block 612), identifying corneal mark locations of the corneal mark in the video measurement in real-time (block 614), and determining a displacement of the corneal mark locations by comparing the corneal mark locations to the reference location (block 616). Such corneal displacement may provide torsion tracking of the patient eye.

[0039] Although Fig. 6 shows example blocks of process 600, in some implementations, process 600 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 6. Additionally, or alternatively, two or more of the blocks of process 600 may be performed in parallel.

[0040] Some of the illustrative aspects of the present invention may be advantageous in solving the problems herein described and other problems not discussed which are discoverable by a skilled artisan.

[0041] While the above description contains much specificity, these should not be construed as limitations on the scope of any embodiment, but as exemplifications of the presented embodiments thereof. Many other ramifications and variations are possiblewithin the teachings of the various embodiments. While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best or only mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the description of the invention. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.

Claims

AMENDED CLAIMS received by the International Bureau on 18 December 2024 (18.12.2024)1. An oculometry apparatus (300) comprising: an interference device (134) operable to at least partially occlude light along a viewing path (140); an infrared light source (102) configured to emit infrared light along an illumination path (160) to irradiate a patient eye with infrared light; an imaging device (170) positioned along an imaging path (162) and operable to measure infrared light reflected by the patient eye; a first polarizer (182) operable to polarize infrared light along the illumination path (160); and a second polarizer (184) operable to polarize light along the imaging path (162) and configured to cross-polarize light that is polarized by the first polarizer (182); and a controller (502) operable to control the operation of each of the interference device (134), the infrared light source (102), and the imaging device (170), the controller (502) being further operable to: operate the interference device (134) to cause the occlusion of optical stimuli along the viewing path (140) to selectively permit or prevent optical stimuli from travelling along the viewing path (140) to form an image of an optical stimuli on a retina of the patient eye; operate the infrared light source (102) to illuminate the patient eye with infrared light; and operate the imaging device (170) to produce an image of the patient eye from the reflected infrared light from the patient eye.

2. The oculometry apparatus (300) of claim 1 wherein: the interference device (134) is operable to transition between a first configuration and a second configuration; when in the first configuration, the interference device (134) has a first relative optical characteristic within the visible spectrum to permit discernible optical sitmuli to be perceived by the retina of the patient; and when in the second configuration, the interference device (134) has a second relative optical characteristic within the visible spectrum that prevents discernible optical stimuli from being perceived by the retina of the patient.

3. The oculometry apparatus (300) of claim 2 wherein:the first relative optical characteristic is a first relative transmittance within the visible spectrum greater than or equal to 20%; and the second relative optical characteristics is a second relative transmittance within the visible spectrum less than or equal to 5%.

4. The oculometry apparatus (300) of claim 2 wherein: the first and second relative optical characteristics are scattering behaviors; and the scattering behavior of the second relative optical characteristic scatters light to a greater magnitude than the first relative optical characteristic.

5. The oculometry apparatus (300) of any one of claims 1-4 wherein the interference device (134) comprises at least one of a liquid crystal device, a polymer dispersed liquid crystal (PDLC) device, a polymer network liquid crystal (PNLC) device, an electrochromic device, a switchable privacy smart film, and a switchable privacy smart glass.

6. The oculometry apparatus (300) of claim 5 wherein the interference device(134) comprises a PDLC and an electrochromic device positioned in optical communication with each other in the viewing path (140).

8. The oculometry apparatus (300) of any one of claims 1-4 further comprising: a variable focus lens positioned optically in front of the imaging device (170) in the imaging path (162); and a fixed focus lens positioned at least one of optically in front of or optically behind the variable focus lens in the imaging path (162).

9. The oculometry apparatus (300) of any one of claims 1-4 wherein the infrared light source (102) comprises a plurality of infrared light emitting devices; wherein the plurality of infrared light emitting devices are spaced apart to irradiate the patient eye from multiple directions.

10. The oculometry apparatus (300) of claim 9 wherein: the oculometry apparatus (300) is comprised by a goggle device (200); andthe plurality of infrared light emitting devices are positioned one of adjacent to and within a spectacle lens of the goggle device (200).

11. An oculometry method comprising the steps of: positioning a patient eye such that it can observe optical stimuli along a viewing path (140); emitting infrared light from an infrared light source (102) along an illumination path (160) of a patient eye; polarizing light as the light travels along the illumination path (160) using a first polarizer (182); selectively operating an interference device (134) between a first configuration with a first relative optical characteristic and a second configuration with a second relative optical characteristic; cross-polarizing light as the light travels along an imaging path between the patient eye and an imaging device (170) using a second polarizer (184); and generating a video measurement of the patient eye by measuring infrared light reflected from the patient eye along the imaging path (162) with the imaging device (170).

12. The oculometry method of claim 11 further comprising: making a corneal mark on a cornea of the patient eye at a reference location with an infrared corneal marker; identifying a reference location of the corneal mark by capturing a reference image of the corneal mark during a calibration process; identifying corneal mark locations of the corneal mark in the video measurement in real-time; and determine displacement of the corneal mark locations by comparing the corneal mark locations to the reference location.

13. The oculometry method of any one of claims 11-12 wherein: the first relative optical characteristic is a first relative transmittance that is greater than or equal to 20%; and the second relative optical characteristic is a second relative transmittance that is less than or equal to 5%.

14. The oculometry method of any one of claims 11-12 wherein: the first and second relative optical characteristics are scattering behaviors; and the scattering behavior of the second relative optical characteristic scatters light to a greater magnitude than the first relative optical characteristic.

15. The oculometry method of any one of claims 11-12 wherein the interference device (134) is one of a liquid crystal device, a polymer dispersed liquid crystal (PDLC), a polymer network liquid crystal (PNLC), an electrochromic device, a switchable privacy smart film, and a switchable privacy smart glass.

16. The oculometry method of claim 15 wherein the interference device (134) comprises a PDLC and an electrochromic device positioned in optical communication with each other in the viewing path (140).

17. The oculometry method of any one of claims 11-12 wherein the infrared light source (102) comprises a plurality of infrared light emitting devices; wherein the plurality of infrared light emitting devices are spaced apart to irradiate the patient eye from multiple directions.

18. The oculometry method of claim 17 wherein: the interference device (134) is comprised by an oculometry apparatus (300) that is positioned within a goggle device (200); and the plurality of infrared light emitting devices are positioned one of adjacent to and within a spectacle lens of the goggle device (200).

Images