Method for determining an indication of a user's visual acuity level - Patent Application 20070122997

Abstract

The present invention relates to the field of computer-implemented methods for determining an indication of a user's visual acuity level, as well as corresponding computer program products and devices. In particular, the present invention relates to methods and devices for facilitating the performance of a vision test in a distributed manner, while still establishing a desired test accuracy regardless of the particular type of device or display, for reliably determining an indication of a user's visual acuity. Accordingly, a computer-implemented method for determining an indication of a user's visual acuity level is proposed, comprising the steps of: performing a vision test using a control unit 14 in communication with a display 16 of a device 10, the display 16 having a predetermined resolution; and displaying the vision test on the display 16 of the device 10, the displayed vision test including a graphical representation 20 including a discontinuity 22, and informing the user 12 to identify the discontinuity 22 by providing a user response. The control unit (14) and display (16) further provide for the optical vision test to be adjusted by generating and displaying discontinuities (22) based on user responses and based on anti-aliasing using one or more pixels of the display (16).

Description

[Technical Field]

[0001] The present invention relates to the field of computer-implemented methods for determining an indication of a user's visual acuity level, and corresponding computer program products and devices. [Background technology]

[0002] Numerous eye diseases exist, which may be acquired or at least partially congenital due to visual behavior or physiological conditions that may predispose people to developing particular eye diseases. In many such instances, early diagnosis of potential risk factors or the onset of eye diseases may be essential to delay the onset, improve the condition of the eye, and / or cure the particular disease. For example, early diagnosis may result in appropriate adjustments or medications to reduce or treat the symptoms experienced.

[0003] To assess the health of their eyes, patients or people at risk of developing eye diseases may therefore need to visit a medical professional, such as an optometrist, where one or more tests may be administered to assist in the assessment of the state of their eyes and the patient's visual performance. Such visits to a doctor's office or clinic or medical institution may be burdensome for the patient, especially when the patient is required to perform such tests on a regular or periodic basis to track the development of eye diseases and / or the patient's visual performance.

[0004] Therefore, it is preferable to perform such tests at a remote location, preferably at the patient's home. Such tests are typically performed in a physician's practice with larger equipment where both the patient and the equipment are located, but such equipment is not present in the patient's home. Thus, the number of tests that can be performed at a remote location may be limited by the available tools, which are limited due to logistics and manufacturing costs, thereby also imposing constraints on the variety of such tests.

[0005] Alternatively, a particular test may be performed on a computer or on a device capable of performing the required test, and the user may use the display of such a device to perform the test. However, since both the type of device and ambient conditions can vary, it is generally difficult to ensure that the test is performed under equal and / or standard conditions. Currently, the user only needs to be given instructions to motivate them to perform the test under appropriate conditions and according to predetermined dimensions.

[0006] Many eye diseases are related to vision, also known as clarity of vision, which depends on optical and neurological factors, and poor vision can result from refractive errors, such as aberrations in the shape of the eye or cornea, astigmatism, and / or reduced flexibility of the lens. Such refractive errors can result in a user or patient becoming nearsighted or farsighted. Furthermore, retinal diseases, such as age-related macular degeneration, can also contribute to poor vision.

[0007] To assess visual acuity, tests are typically performed while the eye is fixed and focused, providing a measurement of central or foveal visual acuity, since visual acuity is typically highest along the center. Furthermore, such tests may be based on the principle of Bernier acuity, a measure of visual acuity that assesses the ability to distinguish the offset between two scale segments that slide parallel to one another. Therefore, when performing such tests, it is important to maintain a specific distance between the subject's eyes and the testing device, e.g., the device's display, to ensure that the test is performed under appropriate conditions and according to predetermined dimensions. This is considered important because device types may vary and testing conditions, including surroundings and user behavior, may be inconsistent. Similarly, the displays of various devices may have different characteristics, particularly different resolutions, resulting in tests that cannot be performed according to common standards or under standardized conditions. Furthermore, the accuracy of such tests or assessment of visual acuity levels may be further limited.

[0008] From WO 98 / 18381 A1, a visual acuity tester is known that uses anti-aliasing to explicitly avoid any aberrations or distortions of standardized characters displayed on a customized display screen. In particular, anti-aliasing is used on the test characters by smoothing jagged edges that arise because the ideal test character shape cannot be accommodated within the pixel array. This allows the characters to be displayed so that the user does not perceive any noticeable distortion, making the characters clear, centered, and visually appealing.

[0009] A further problem is the lack of intuitiveness when actually performing the test, because such tests typically require the user to perform manual adjustments to correct the indicated misalignment. Such manual adjustments may require the activation of one or more buttons, be time-consuming, and therefore may not be perceived as user-friendly. Furthermore, the risk of manual error increases when performing the test under such conditions. Furthermore, manual adjustments can make it difficult to maintain proper conditions for performing the test, especially since such tests are often time-consuming.

[0010] Therefore, what is needed is a method and apparatus that facilitates administering vision tests in a distributed manner while establishing a desired testing accuracy, regardless of the particular type of device, to reliably determine a user's visual acuity level. Summary of the Invention [Problem to be solved by the invention]

[0011] SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus for determining a user's visual acuity that ameliorates the above-mentioned undesirable problems. [Means for solving the problem]

[0012] This object is achieved by the independent claims. Preferred embodiments are set forth in the dependent claims, the description and the drawings.

[0013] Therefore, in a first aspect, there is proposed a computer-implemented method for determining a user's visual acuity level, comprising the steps of: performing an optical vision test using a control unit in communication with a display of the device, the display having a predetermined resolution; and displaying an optical vision test on a display of the device, the displayed optical vision test including a graphical representation including a discontinuity, and prompting a user to identify the discontinuity by providing a user response; Using the control unit and the display, the optical vision test is adjusted by generating and displaying discontinuities based on user responses and based on anti-aliasing using one or more pixels of the display.

[0014] The use of anti-aliasing allows the range of possible discontinuities, and therefore the range of visual acuity levels to be measured, to be increased. Thus, discontinuities are generated and displayed using one or more pixels of the display and based on anti-aliasing using the control unit and the display.

[0015] Such anti-aliasing is based on the fact that pixels can not only be presented as black or white, but can also essentially contain or present any particular grayscale color in between. A user may more easily perceive a pixel shift of a black pixel, i.e., move a black pixel toward an adjacent pixel and present the previous pixel position as a white pixel, but may not perceive a gradient shift, for example, a previous black pixel is reduced to 90 percent intensity and an adjacent white pixel is increased to a black pixel intensity with 10 percent pixel intensity. In other words, in the first case, a user may detect the pixel shift as a cross pixel, but may not notice such a gradient shift.

[0016] In particular, for lines having a particular pixel thickness, e.g., 4 to 6 or 5 pixels, anti-aliasing can be provided such that the offset between such lines can be provided not only by a full pixel, but also by providing a gradient shift, and not only can outer pixels contribute to such a gradient shift, but more centrally located pixels can also exhibit such a gradient shift, thereby further increasing the precision and level of detail of vision testing, thereby providing support for medically significant levels of vision that were previously unidentifiable using standard displays and full pixel shifts.

[0017] Thus, providing discontinuities based on anti-aliasing can be thought of as intentionally providing deviations or (gradient) shifts in areas of the structure of the graphical display that can preferably indicate particular visual acuity levels, with anti-aliasing allowing for improved visual acuity testing resolution.

[0018] Moreover, display resolution is taken into account, so that, depending on, for example, the size and pixel density of the display, the displayed vision test can have different dimensions, thus allowing the vision test to be run on a variety of devices without significantly changing its appearance to the user.

[0019] For example, the computer-implemented method may be performed on a laptop computer, notebook, tablet, or other portable handheld device such as a personal digital assistant (PDA), and the method may be implemented in a module or stored as computer-readable instructions stored on or otherwise provided to the device. Such instructions may then be executed by the device's control unit, which in certain embodiments may be provided as a processor or integrated microprocessor, preferably communicatively coupled to on-board memory and / or storage media.

[0020] As outlined above, the display further comprises or exhibits a resolution which may be defined as the pixel density multiplied by the size or area of the display, this area being defined by the extension of the display in the length and perpendicular to the length of the device, e.g., the height and width of the display. Thus, knowing the resolution of the display, the control unit can adjust or adapt the displayed vision test to display the vision test according to predetermined dimensions.

[0021] The adaptation of the vision test is not limited to a particular type of vision test and can be implemented for both testing based on Bernier acuity and testing shape variations. In either case, anti-aliasing provides a gradient shift rather than a full pixel shift, thereby further increasing the accuracy and level of detail of the vision test.

[0022] The term "adjusting" should be understood to include both the initial setting of the display and changing the setting during the administration of the vision test, for example based on the user's response. The adjustment or setting may be performed by providing corresponding display or control signals to the display or display unit, thereby enabling the display to present the vision test according to predetermined dimensions.

[0023] It will be understood that when referring to a predetermined dimension, the displayed vision test may include a particular size and / or magnification in at least one direction of the display. As explained above, the control unit may output control signals to the display to, for example, increase the size or magnification of the displayed vision test, such that the vision test is displayed on only a portion of the display, or may expand on the display until it essentially covers the entire display. The variable spanning further depends on the resolution of the display, such that a display with a lower resolution may require a fewer number of pixels to be activated compared to a display with a higher pixel density.

[0024] To further optimize the user's experience when performing the test, the displayed optical vision test preferably includes or essentially consists of a graphical display that is displayed in black on a white background. Such a feature not only provides an easily recognizable graphical display, but also reduces the perception of ambient glare. In other words, even under conditions with strong ambient light, the user can still see the graphical display and perform the vision test without requiring significant effort, which could potentially make performing the vision test difficult or strenuous.

[0025] The method allows for various types of optical vision tests to be performed, and the dimensions of the displayed vision test can be adapted based on the resolution of the display. Preferably, the displayed optical vision test includes at least two lines, and the adjustment includes adjusting the size, length, and / or thickness of the lines. Thus, the lines can have the same overall appearance across various devices with different resolutions.

[0026] For example, the thickness of a line may consist of a certain number of pixels (e.g., 5 pixels), but the width or thickness of the line may be adapted accordingly, so that, for example, an (ultra) high resolution display can use a larger number of pixels compared to a display having a lower resolution, and the thickness perceived by the user will be essentially the same.

[0027] When administering the optical vision test, the displayed optical vision test includes a graphical representation including the discontinuity and prompts the user to identify the discontinuity by providing a user response. Based on the user response, the optical vision test can then be adjusted using the control unit.

[0028] The discontinuities may be provided as irregularities in shape, for example, by a circle with bumps or gaps of a certain size, or by two lines arranged along a vertical axis, offset from a continuous line, the lines being offset vertically. Larger discontinuities may be more easily identified by the user, while smaller discontinuities are less obvious and may therefore form a measure for determining the user's visual acuity level. Based on the user response, i.e., whether the user correctly identified the discontinuity or not, the control unit can evaluate the user response and determine the visual acuity level, for example, based on a scoring and / or averaging algorithm.

[0029] To further facilitate interaction with a user performing a vision test, the discontinuities are preferably aligned along the length of the display, and a user response is received by the control unit by selection of an indication associated with the discontinuity, and the graphical display includes an indication on opposite ends of the graphical display.

[0030] For example, rather than adjusting or correcting the displayed misalignment, the user is simply required to indicate whether a discontinuity exists, making the visual acuity test easier and more intuitive to perform, thereby improving the user experience and reducing the time required to perform the visual acuity test. Furthermore, this may also motivate the user to perform such tests more frequently, so that the tests are more likely to be performed according to the predetermined intervals. This may increase the likelihood that the onset of macular degeneration or other factors that may affect the user's vision will be detected at an earlier stage, so that corrections or treatments can be implemented accordingly.

[0031] Having displays on opposite ends further ensures that the user's focus is maintained at the center of the display, with discontinuities preferably displayed in the center, so that any interfering objects and variables from the periphery of the device are screened out as much as possible, and the display surrounding the graphical display can be configured to provide a more uniform appearance when the user is performing the vision test.

[0032] To further facilitate user interaction and performance of the vision test, the display is preferably configured as a touchscreen, and user responses are received by the control unit using tactile interaction with the touchscreen at or in the direction of the area of the display corresponding to the indication. Such an approach ensures that users can trigger user responses using interactions that can also be applied to other handheld devices. A user can trigger a user reaction, for example, by tapping with a finger or swiping a finger from a central location on the display to the corresponding edge containing the indication. This eliminates the need for cumbersome adjustments and allows the user to maintain focus on the center of the display.

[0033] Furthermore, instead of, for example, detecting irregularities in shapes or selecting shapes with irregularities compared to shapes with a continuous appearance, the graphical display preferably includes at least two lines. The at least two lines are arranged essentially along the longitudinal direction of the display, and discontinuities are formed as offsets of the lines in a direction perpendicular to the longitudinal direction of the display. As explained above, the lines may thus be aligned essentially along the same axis to form a continuous line, but offset from each other starting from the connecting end, i.e., in a staggered manner. In such cases, the user may be required to indicate whether the lines form a continuous line or are discontinuous, and the displayed offset is a measure of the user's visual acuity level.

[0034] Therefore, an indication of the user's visual acuity level is preferably determined using the control unit based on the user's response.

[0035] To determine the visual acuity level indication, the visual acuity test may be performed by the control unit in two steps: in a first step, an initial visual acuity level indication is determined; and in a second step, the initial visual acuity level is refined and / or confirmed as a final visual acuity level indication. In other words, the first step can provide an estimate of the visual acuity level, while in the second step, a more precise test or fine-tuning of the visual acuity level indication is performed to determine the final score or indicated visual acuity level. This has the advantage that the first step can be performed more quickly, while the two steps can be separated, i.e., performed at different times. This may be perceived as more comfortable because the test takes less time and the separation between the two steps can be shorter due to the shortened time span.

[0036] Although vision tests generally do not provide a diagnosis, the results may be used as a visual acuity estimate and may obviate the need for further testing. Instead, vision tests generally provide an indication for a physician to assess visual performance to assist in making a diagnosis.

[0037] In a preferred embodiment, in a first step, the graphical representation includes a discontinuity corresponding to a first acuity level. If the user response correctly identifies the discontinuity, the control unit adjusts the visual acuity test by displaying on the display a further graphical representation including a discontinuity corresponding to a second acuity level and prompting the user to identify the discontinuity by providing a user response, the second acuity level being higher than the first acuity level. If the user response does not identify the discontinuity, the control unit sets the initial acuity level indication to a predetermined initial acuity level lower than the first acuity level.

[0038] Visual acuity levels can be scored with reference to the logarithm of the minimum angle of resolution, also known as the LogMAR value. Using this scaling, an observer who can resolve details as small as 1 arcminute of visual angle would be considered to have a LogMAR of 0, since the logarithm of base 10 is 0. Similarly, an observer who can resolve details as small as 2 arcminutes of visual angle would be considered to have a LogMAR of 0.3, since the logarithm of base 2 is approximately 0.3, with higher values indicating correspondingly reduced visual acuity. Thus, using discontinuities, offsets in the graphical display can correspond to specific LogMAR values, such that a graphical display can be displayed that includes a continuum with increasing visual acuity levels, starting from a first visual acuity level corresponding to, for example, a LogMAR value of 0.7, and extending to, for example, LogMAR −0.7. If the user is unable to identify the first visual acuity level, the initial visual acuity level or estimated threshold indication can be set to a lower visual acuity level, for example, LogMAR 1.0.

[0039] On the other hand, if the user response correctly identifies the discontinuity according to the second visual acuity level, the method may further include using the control unit to adjust the visual acuity test by displaying a further graphical representation on the display, which may include a discontinuity corresponding to a visual acuity level higher than the previous visual acuity by a predetermined amount, and prompt the user to identify the discontinuity by providing a user response. This step is repeated if the user response correctly identifies the discontinuity, thereby achieving an indication of the initial visual acuity level, typically until a predetermined maximum visual acuity level is achieved, or until the user response no longer identifies the discontinuity.

[0040] Continuing with the above example, a user may be presented with a discontinuity corresponding to a first visual acuity of 0.7 LogMAR. After identifying the discontinuity, subsequent graphical displays may include reduced LogMAR values, i.e., higher visual acuity values, by a predetermined amount, such that a second graphical display may correspond to a LogMAR value of 0.4, with a delta value of 0.3. Similarly, once a discontinuity is correctly identified by the second graphical display, a third graphical display may be displayed, with the discontinuities adjusted to achieve a LogMAR of 0.1, for example, until a predetermined maximum LogMAR of -0.7 is achieved. The predetermined amount may vary between stages, such that the first set of graphical displays corresponds to a larger visual acuity difference, with smaller differences between discontinuities toward the maximum LogMAR value, thereby providing an improved estimate of the initial visual acuity level.

[0041] However, if the user's response does not identify the discontinuity, for example a second or subsequent discontinuity, the method may further include performing the step of adjusting the vision test by displaying a further graphical representation on the display using the control unit. The further graphical representation may include a discontinuity corresponding to a lower visual acuity level than the previous visual acuity by a predetermined amount, and may prompt the user to identify the discontinuity by providing a further user response; - if further user responses do not identify a discontinuity, this step is repeated and the initial acuity level indication is set to the acuity level corresponding to the last displayed discontinuity until a discontinuity is correctly identified, the first acuity level is achieved, or a total of two subsequent discontinuities have not been identified; or - if the further user response identifies a discontinuity, the method further comprises performing a step of adjusting the vision test by using the control unit to display on the display a further graphical representation including a discontinuity corresponding to a higher vision level than the previous vision by a predetermined amount, and notifying the user to identify the discontinuity by providing a further user response, and if the further user response identifies a discontinuity, this step is repeated until no discontinuities are identified or until a maximum vision level is achieved, and the indication of the initial vision level is set to the vision level corresponding to the last displayed discontinuity.

[0042] Again, following the above example based on LogMAR values, a second visual acuity level may correspond to, for example, a LogMAR value of 0.4. If no discontinuities are identified, the control unit may increase the LogMAR value by a predetermined Δ value, for example, 0.2, such that subsequent discontinuities displayed correspond to a LogMAR value of 0.6. Similarly, if the user identifies a third discontinuity corresponding to a Δ value of, for example, -0.1, but does not identify a fourth discontinuity having a LogMAR value of, for example, 0.4, the control unit may increase the LogMAR value by a predetermined Δ value, for example, +0.1, such that the display displays a further graphical representation with a LogMAR value of 0.5.

[0043] In such a scenario, two options exist. If the user does not identify a discontinuity, then a further graphical display prompting the user to identify a discontinuity is displayed, with the LogMAR value of each subsequent discontinuity being increased by a predetermined amount, or Δ value. This sequence is stopped once a discontinuity is correctly identified or until the first acuity level is achieved. For example, a graphical display with a LogMAR value of 0 may not be identified, and the next discontinuity may correspond to a LogMAR value of 0.1. If the user identifies a discontinuity, the initial acuity level indication is set to a LogMAR value of 0.1. However, if the user does not identify any of the subsequent discontinuities and reaches the first acuity level, for example, 0.7, the control unit sets the initial acuity level indication to the first acuity level.

[0044] Alternatively, to reduce potential errors and speed up the vision test, i.e., the first step of the vision test, the initial vision level indication may also be set to the vision level corresponding to the previously displayed discontinuity after a total of two discontinuities, preferably after no subsequent discontinuities are identified.

[0045] A second option provides that if a further user response identifies a discontinuity, the visual acuity test is adjusted by displaying a further graphical display including a discontinuity corresponding to a higher visual acuity level than the previous visual acuity level by a predetermined amount and prompting the user to identify the discontinuity by providing a further user response. For example, an initial increase in the LogMAR value, e.g., to 0, may be identified by the user, and the subsequently displayed graphical display may include a discontinuity corresponding to a LogMAR value of -0.1, and a decrease in the LogMAR value may be performed by a predetermined amount or Δ value of 0.1. This step provides both an initial fine-tuning adjustment and a reduction of any potential statistical error. If the user identifies a subsequent discontinuity, e.g., corresponding to a LogMAR value of -0.3, the steps are repeated until no discontinuities are identified, and the initial visual acuity level indication is set to the visual acuity level corresponding to the value. Similarly, if the user reaches a maximum visual acuity level, e.g., corresponding to a LogMAR value of -0.7, the initial visual acuity level indication is set to the visual acuity level corresponding to the maximum LogMAR value.

[0046] After obtaining the indication of the initial visual acuity level, the method may perform a second step in which a pool of graphical representations is generated, each graphical representation including a discontinuity corresponding to a particular visual acuity level. The pool typically includes a predetermined number of graphical representations having discontinuities according to the indication of the initial visual acuity level, and further includes a predetermined number of graphical representations having discontinuities corresponding to higher visual acuity levels than the indication of the initial visual acuity level having a predetermined amount, i.e., corresponding to lower LogMAR values. The visual acuity test is adjusted by using the control unit to display on the display a graphical representation randomly selected from the pool and by prompting the user to identify the discontinuities, and the method may include: - if a further user response identifies a discontinuity and a graphical representation having a discontinuity corresponding to an acuity level has not already been added to the pool and is not greater than the predetermined amount from the initial acuity level indication, adding a predetermined number of graphical representations having a discontinuity corresponding to an acuity level higher than the acuity level indication by a predetermined amount; and / or - if further user responses do not identify discontinuities and graphical representations having discontinuities corresponding to acuity levels have not yet been added to the pool and do not exceed a predetermined amount from the representation of the initial acuity level, adding to the representation of the initial acuity level a predetermined number of graphical representations having discontinuities corresponding to acuity levels lower than the representation of the initial acuity level; Here, the graphical representations are displayed in succession, each displayed graphical representation is removed from the pool as a user response is received, and a final acuity level indication is determined based on the user response.

[0047] For example, an initial visual acuity level indication may be obtained corresponding to a LogMAR value of -0.3. In this case, a pool may be generated by including a predetermined number of graphical representations with discontinuities corresponding to, for example, -0.3, three. The pool may further include a predetermined number of graphical representations with discontinuities corresponding to higher visual acuity levels, the predetermined amount corresponding to, for example, a LogMAR delta value of 0.1, such that a predetermined number of graphical representations with discontinuities corresponding to, for example, -0.4, three, are also added to the pool. While the predetermined number may be provided in one embodiment, it is provided for illustrative purposes only and may vary for each group of graphical representations or visual acuity levels. Similarly, the predetermined amount may also correspond to a higher or lower value depending on the desired accuracy of the visual acuity level to be determined.

[0048] After the pool is generated, random graphical representations are displayed and the user is prompted to identify the graphical representations. In this case, the user can either correctly identify the discontinuities or, for example, perceive the discontinuities as a continuous graphical representation. In the former case, a predetermined number of graphical representations having discontinuities corresponding to acuity levels higher than the initial acuity level indication having a predetermined amount are added to the pool. However, this is only true if a graphical representation having a discontinuity corresponding to an acuity level has not already been added to the pool and the level does not exceed the predetermined amount from the initial acuity level indication.

[0049] In other words, if a randomly displayed graphical display includes a discontinuity corresponding to a LogMAR value of -0.4, a graphical display having a discontinuity of higher visual acuity, e.g., corresponding to a LogMAR value of -0.5, will not exceed a predetermined amount, e.g., a LogMAR of -0.7 or a LogMAR of 1, for a LogMAR of 0.4. Furthermore, after the creation of the initial pool, graphical displays including discontinuities corresponding to visual acuity levels may not be added. Thus, a predetermined number of graphical displays having discontinuities corresponding to, e.g., a LogMAR of -0.5, i.e., higher visual acuity, are added to the pool. In the above example, the initial pool may include a total of six graphical displays, three discontinuities corresponding to a LogMAR value of -0.3 and three discontinuities corresponding to a LogMAR value of -0.4. After identifying the discontinuity corresponding to a LogMAR value of -0.4, three additional graphical displays having discontinuities corresponding to, e.g., a LogMAR value of -0.5, are added to the pool. When the first displayed graphical representation is removed from the pool, the pool consists of a total of eight graphical representations, with three discontinuities corresponding to a LogMAR value of −0.3, three discontinuities corresponding to a LogMAR value of −0.5, and two discontinuities corresponding to a LogMAR value of −0.4.

[0050] This addition is performed because the additional graphical representation corresponding to the respective LogMAR value has not yet been added to the pool and the higher acuity level did not exceed a predetermined offset from the indicated initial acuity level. On the other hand, if the additional displayed graphical representation also has a discontinuity corresponding to a LogMAR value of -0.3, then the additional graphical representation is not added to the pool upon correct identification because a graphical representation with a discontinuity having a higher acuity level has already been added.

[0051] If further user responses do not identify a corresponding discontinuity to, for example, a LogMAR value of −0.4, then a predetermined number of graphical displays having a discontinuity corresponding to an initial visual acuity indication, for example, to a LogMAR value of −0.3, are not added because a graphical display including the corresponding discontinuity was already added when the pool was created. On the other hand, if further user responses do not identify a corresponding discontinuity to, for example, a LogMAR value of −0.3, then a predetermined number of graphical displays having a discontinuity corresponding to, for example, a LogMAR value of −0.2 are added because such a corresponding visual acuity level has not yet been added and the visual acuity level does not exceed a predetermined tolerance range, for example, from −0.7 to 1 LogMAR.

[0052] After the graphical display is displayed and the corresponding user response is received, when the pool does not contain any further graphical displays, a final acuity level indication is determined based on the user response. Preferably, the final acuity level indication corresponds to the highest acuity level last correctly identified, or the final acuity level indication may be determined as the highest acuity level at which a majority of the user responses correspond to the identification of discontinuities. For example, if two out of three discontinuities corresponding to the same, highest acuity level are correctly identified, the acuity level is used as the final estimate or assessment of the acuity level. However, if a majority of the user responses do not correspond to the identification of discontinuities, the final acuity level indication may be determined as the next acuity level at which such a majority was determined.

[0053] Alternatively, or additionally, this may be done, for example, by evaluating the user responses and performing statistical analysis and / or averaging the corresponding scores defined by each user response and the corresponding visual acuity level.

[0054] Generating the pool preferably includes evaluating user responses of a predetermined number of graphical displays having discontinuities according to the indication of the initial acuity level, wherein a further predetermined number of graphical displays have discontinuities corresponding to a higher acuity level than the indication of the initial acuity level having the predetermined amount if a majority of the user responses correspond to identifying the discontinuity, or have a lower acuity level than the indication of the initial acuity level having the predetermined amount if a majority of the user responses do not correspond to identifying the discontinuity. Thus, following the above example, the initial pool may consist of three graphical displays having discontinuities according to the indication of an initial acuity level of -0.3 LogMAR and three graphical displays having discontinuities corresponding to an acuity level of -0.4 LogMAR.

[0055] It may further be envisioned that when performing an optical vision test, the alignment of the graphical display may be switched to a longitudinally perpendicular alignment or, when the second step is performed, the device may be rotated from an upright position to a laterally extending position. In other words, the user may maintain the display in an upright position while performing the first step of the vision test. The orientation of the graphical display may be automatically rotated, or the user may be required to rotate the display approximately 90 degrees when performing the second step. This ensures that vision is tested in at least two orientations and that the user may be incentivized and motivated to continue the vision test due to variations in orientation.

[0056] To maintain a predetermined distance, the device may further include an optical sensor, and the method may provide that a warning is output if the user is not within a predetermined range, i.e., too far or too close to the display.

[0057] More preferably, the method further comprises the step of detecting at least a facial characteristic of the user by the control unit using an optical sensor of a device in communication with the control unit, and the control unit determining a distance between the display and the detected facial characteristic of the user based on the detected facial characteristic, and adjusting the displayed optical eye test based on the determined distance and resolution.

[0058] According to a preferred embodiment, the user is about 35 cm to about 45 cm, preferably about 40 cm, from the display, so the user must either adapt their position relative to the display or remain in a stationary position at any point during the performance of the vision test.

[0059] According to another embodiment, determining the distance between the display and the user's facial features or face allows for automatic adaptation of the visual acuity test displayed on the display, ensuring that the user perceives the test at the appropriate dimensions. In other words, approximately the same visual acuity level can be determined at various distances so that any deviation from the predetermined distance can be taken into account. This simplifies the administration of the visual acuity test while increasing its validity, i.e., the user does not need to constantly change their position relative to the display or remain in a stationary position at any time during the administration of the visual acuity test.

[0060] The predetermined dimension corresponds to a determined distance between the display and the user's face. For example, if the user changes their position relative to the display, the control unit can increase the dimension in at least one direction accordingly to ensure that the overall appearance of the vision test remains essentially the same. When referring to the predetermined dimension, it will be understood that the displayed vision test can include a specific size and / or magnification in at least one direction of the display. As described above, the control unit can output control signals to the display to, for example, increase the size or magnification of the displayed vision test as the distance between the user and the display increases, so that rather than being displayed on only a portion of the display, the vision test can expand on the display until it essentially covers the entire display, depending on the determined distance. The variable spanning further depends on the resolution of the display; thus, a display with a lower resolution may require fewer pixels to be activated compared to a display with a higher pixel density. Thus, the control unit of the device can adjust the displayed vision test based on the determined distance to the user interacting with the device to perform the vision test.

[0061] Facial features are preferably detected by an optical sensor, which may be configured to determine the presence of a facial feature based on detected signals indicative of a particular distance range, e.g., contrast level, object size, etc., e.g., using feature recognition to detect particular features such as eyes, nose, or overall shape, for example between 20 cm and 70 cm. The optical sensor may consist of a plurality of sensor elements, preferably arranged in an array, preferably provided as a camera or camera sensor.

[0062] In addition to, or as an alternative to, determining distance, the displayed optical vision test may be further adjusted by the control unit based on ambient brightness, contrast, and / or hue detected by the optical sensor, or alternatively, the user may adjust these conditions accordingly.

[0063] For example, the brightness and hue may vary, e.g., throughout the day, and may further depend on the user's surroundings, e.g., whether the user is currently located in an indoor environment or an outdoor location. Furthermore, such ambient conditions may change depending on environmental factors such as the weather and both the user's geographic and angular position of the sun. According to certain embodiments, the control unit may therefore take into account changing ambient conditions such that the appearance of the displayed vision test to the user can be adjusted accordingly, such that the displayed vision test remains essentially the same under changing ambient conditions.

[0064] Preferably, the adjustment includes adjusting the brightness, contrast, and / or hue of the display. For example, the control unit may send a control signal to the display indicating increased brightness and / or a hue with more blue tones when detected brightness is reduced, e.g., if the vision test is performed in the morning or late afternoon instead of mid-morning. It may also indicate increased contrast when high brightness is detected, e.g., if the room lights are on or if the vision test is performed during the day instead of at night. Thereby, the overall appearance to the user does not change significantly, thereby further increasing the validity of the vision test by maintaining and adapting light conditions based on the experienced ambient lighting.

[0065] In the case of a handheld device, the user may further interact with the device in various positions, and the attitude and angle of interaction with the device may vary. For example, a user may use a laptop computer, which may be placed on a stable surface, but the user may interact with the laptop from various heights and at various angles. Similarly, the mobile device may be held, for example, at waist height or chest or eye height, and the angle between the user's face and the display may vary accordingly. Thus, the angle between the display and the detected characteristics of the user's face may be determined, preferably using a control unit, and the displayed optical eye test may be adjusted based on the determined angle. For example, the displayed eye test may be displayed in perspective according to the determined angle, and the magnification of the displayed eye test may be adjusted accordingly.

[0066] This further increases the stability of the testing conditions, so that the vision test can be performed under essentially standard conditions: the user can, for example, tilt the device, but the displayed vision test has a static appearance so that the user always perceives the displayed vision test in essentially the same way.

[0067] The adjustments can be performed continuously or periodically. For example, slight deviations in the signal detected by the optical sensor can be ignored based on a predetermined threshold, and / or can be evaluated over time to, for example, make periodic adjustments if the deviations persist over a predetermined period of time. Alternatively, the displayed visual acuity test can be continuously adjusted, for example, every 5-10 seconds, with the adjustment speed preferably being manually selected depending on the user's preferences and / or the user's particular condition.

[0068] To further optimize the user's experience when performing the test, the displayed optical vision test preferably includes or essentially consists of a graphical display that is displayed in black on a white background. Such a feature not only provides an easily recognizable graphical display, but also reduces the perception of ambient glare. In other words, even under conditions with strong ambient light, the user can still see the graphical display and perform the vision test without requiring significant effort, which could potentially make performing the vision test difficult or strenuous.

[0069] The method allows for various types of optical vision tests to be performed, and the dimensions of the displayed vision test can be adapted accordingly based on both the resolution of the display and the determined distance between the display and the user. Preferably, the displayed vision test includes at least two lines, and the adjustment includes adjusting the size, length, and / or thickness of the lines. Thus, the lines can have the same overall appearance not only across various devices with different resolutions, but also when the user is at various distances from the display.

[0070] For example, the thickness of a line may be composed of a predetermined number of pixels, but the width or thickness of the line may be adapted accordingly, for example, so that a (super) high-resolution display can use more pixels compared to a display with a lower resolution, so that the thickness perceived by the user is essentially the same. However, the thickness may not be adjusted based on the determined distance. Thus, the thickness remains the same for all distances determined between the user and the display when performing a vision test on the same device. In contrast, however, the length of the line may be adapted according to the determined distance, so that the user perceives the vision test in a similar or essentially identical manner at various distances.

[0071] The above objects are further achieved by a computer program product embodied on a computer-readable storage medium and configured to perform the operations of the computer-implemented method as described above when executed on a processor.

[0072] For example, the computer program product may be configured as a module that is stored in the device's memory or saved on a flash drive, SSD or HDD, or may even be embodied on a portable storage device.

[0073] The above object is further achieved by an apparatus for determining a user's visual acuity level, the apparatus comprising a control unit, a display and optionally an optical sensor, the apparatus being configured to perform a computer-implemented method as described above.

[0074] Preferably, the device is configured as a portable and / or handheld device so that the user can carry the device, thus facilitating the execution of the method at any desired remote location. Furthermore, this provides that the computer-implemented method may be executed on the user's device, which is used for other purposes, so that a separate device is not required to execute the method. Preferably, the device is configured as a mobile terminal, and the optical sensor may be implemented as an integrated camera. The camera is preferably a front-facing camera near the display, so that the user does not need to rotate or turn the mobile terminal, for example, to provide periodic adjustments of the optical vision test based on signals received by the camera. Furthermore, this also provides that continuous adjustments of the test can be performed so that optimized standard conditions are established at any point during the execution of the optical vision test.

[0075] The device may further include a wireless communication module, and the control unit is configured to perform the optical vision test using data received from the wireless communication module and / or to transmit the determined vision level to a remote device using the wireless communication module.

[0076] For example, the optical vision test may not be temporarily stored, e.g., in the device's memory, or may be temporarily stored, and data or instructions necessary to administer or perform the optical vision test may be received via the wireless communication module, e.g., from a cloud server or a network interface. Such an approach ensures that any updates to the optical vision test are performed automatically and that required storage space on the device may be reduced or minimized. Alternatively, or additionally, the wireless communication module may enable the determined vision level to be automatically reported, e.g., to a medical professional, so that vision development can be tracked and monitored. For example, this may include the user's response and corresponding vision level, a determined indication of the initial vision level, and / or a final vision level, depending on the level of detail required to track and / or monitor vision development. [Brief explanation of the drawings]

[0077] The present disclosure will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings. [Figure 1] FIG. 1 is a graphical representation of an apparatus for determining an indication of a user's visual acuity level. [Figure 2A] FIG. 2A is a schematic diagram of a display showing a graphical representation with discontinuities in different orientations. [Figure 2B] FIG. 2B is a schematic diagram of a display showing a graphical representation with discontinuities at different orientations. [Figure 3A] FIG. 3A schematically depicts a method for using anti-aliasing in a graphical display that includes discontinuities. [Figure 3B] FIG. 3B schematically depicts a method for using anti-aliasing in a graphical display that includes discontinuities. [Figure 4] FIG. 4 shows schematically the steps for determining an indication of an initial visual acuity level according to the first step of an optical vision test. [Figure 5] FIG. 5 shows schematically the steps for determining an indication of the final visual acuity level according to the second step of the optical visual acuity test. DETAILED DESCRIPTION OF THE INVENTION

[0078] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following, the present invention will be described in more detail with reference to the accompanying drawings, in which identical elements are given identical reference numerals and repeated descriptions may be omitted to avoid redundancy.

[0079] As shown in FIGS. 2A and 2B , the graphical display 20 on the display 16 can be displayed in different orientations, for example, during different phases of an optical vision test. Thus, as shown in FIG. 2A , the graphical display 20 and discontinuities 22, shown here as a variation of a Bernier vision test, are aligned along the longitudinal or vertical axis of the display 16, so that the lines form extensions of one another and are separated only by the discontinuities 22 in a staggered manner with a certain offset or gap. While the user may be prompted to rotate the device to rotate the display, as shown in FIG. 2B , the orientation of the graphical display 20 can also be automatically changed by a 90-degree rotation so that it is perpendicular to the longitudinal direction of the display 16. In other words, the vision test can be performed in an upright or vertical orientation, but the vision test can be switched to a laterally extending or essentially horizontal orientation to provide variation in the vision test and to provide different testing aspects.

[0080] Additionally, the visual acuity test includes indicia 28A, 28B located at opposite ends of the graphical display 20, whereas in the case of a horizontal or vertical orientation of the graphical display 20, the indicia 28A, 28B are located at opposite longitudinal ends of the display 16. The indicia 28A, 28B allow the user to provide a user response, with the indicia 28A, 28B indicating whether the user perceives the graphical display 20 as continuous or discontinuous, respectively. To select each indicia 28A, 28B, the display 16 according to the preferred embodiment is configured as a touchscreen, allowing the user to tilt at the respective area of the display 16 or swipe to the respective indicia 28A, 28B from, for example, a central position on the display 16.

[0081] To further increase the level of accuracy and visual acuity variation in response to discontinuities, the control unit implements anti-aliasing techniques, as shown schematically in Figures 3A and 3B. Thus, as explained above, pixels are not only presented as black or white, as shown in Figure 3A, but can also essentially contain any particular grayscale color between them, such that a gradient shift can be performed, as shown in Figure 3B. In this example, a previously black pixel is reduced, for example, to 90 percent intensity, and an adjacent white pixel is increased to a black pixel intensity, for example, with a pixel intensity of 10 percent. Thus, although a full pixel shift is not provided, a user may or may not perceive the gradient shift as a cross-pixel shift.

[0082] Thus, the size and resolution of discontinuities may not be limited by the number of pixels, but may be further increased using the gradient shift provided by anti-aliasing techniques, and thus the user's visual acuity level may be determined with greater precision. This may further increase the precision and level of detail of visual acuity testing, thereby providing support for medically significant visual acuity levels previously unidentifiable using standard displays and full pixel shifting. For example, LogMARs of -0.7 or higher may be obtained, depending on the available resolution.

[0083] 1, a graphical representation of an apparatus 10 for determining an indication of a user's 12's visual acuity level is shown schematically. The apparatus 10 according to this embodiment is a handheld device in the form of a mobile terminal and is configured to perform an optical visual acuity test. To do so, the apparatus 10 includes a control unit 14 in communication with a display 16, and provides control or display signals to the display 16 to output and display the optical visual acuity test to the user 12. The optical visual acuity test may be embedded in a storage medium of the apparatus, for example in the form of executable instructions.

[0084] The control unit 14 may be provided, for example, as a microprocessor embedded on a chip of the mobile terminal, and may be configured to process and evaluate a number of received signals, among which, according to a preferred embodiment, are signals received from an optional optical sensor 18, which is integrated into the device on the front side and positioned close to or adjacent to the display 16. The optical sensor 18 in this embodiment is part of an integrated camera of the device and is configured to detect optical signals.

[0085] Thus, the control unit 14 can use the optical sensor 18 of the device 10 to determine or detect one or more facial characteristics of the user 12. For example, feature recognition can be used to determine specific features, such as the eyes, nose, or overall shape, based on the received optical signals. However, the optical sensor 18 and / or the control unit 14 may be configured to determine the presence of facial features based on detected signals that indicate a specific distance range, for example, between 20 cm and 70 cm, for contrast levels and / or object sizes. Thus, facial structures or features are not directly identified, but are determined based on specific contrast differences of objects in the vicinity of the optical sensor 18, for example. Using the optical signals, the control unit 14 can then determine the distance 24 between the display 16 and the face of the user 12.

[0086] By knowing the distance 24 between the display 16 and the user 12, the control unit 14 can adjust the optical vision test accordingly. When performing the optical vision test, the user 12 is presented with a number of graphical representations 20 that are displayed on the display 16. Each graphical representation 20 includes a discontinuity 22 that is preferably located in a central region of the display 16, as shown in FIG. 3. This has the advantage that the distance 24 between the user 12 and the display 16 corresponds to the distance 24 between the discontinuity 22 and the user 12, with the primary focus being at the discontinuity 22.

[0087] Optionally, based on the determined distance 24, the control unit 14 may then adjust the size or magnification of the displayed graphical representation 20 so that the user 12 perceives the same appearance of the graphical representation 20 and the discontinuity 22 at various distances. The user 12 is thereby provided with improved testing conditions, which may be essentially the same during the performance of a vision test and between vision tests performed at different times. A warning signal may also or instead be output to indicate that the user is moving outside of the preferred range; such adaptation prevents the user 12 from accidentally approaching the discontinuity 22 or being at a distance 24 that makes the discontinuity 22 more difficult to identify. Thus, the validity of the indication of the visual acuity level determined by performing a vision test is enhanced.

[0088] Adjustments to the graphical display 20 are further performed based on the resolution of the display 16, thereby taking into account the pixel density and size or dimensions of the display 16. This allows the test to be performed with similar accuracy across devices with different resolutions, so that the user is always presented with a graphical display having a similar size and magnification.

[0089] Additionally, control unit 14 may optionally determine an interaction angle 26 of user 12 with device 10 or display 16. Based on the determined angle 26, control unit 14 may adjust the displayed optical eye test by adjusting the displayed strabismus of graphical display 20 according to determined angle 24, and the magnification of the displayed eye test may be adjusted accordingly. Thus, as user 12 tilts device 10, the displayed eye test may have an essentially static appearance such that user 12 always perceives the displayed eye test in essentially the same way.

[0090] Moreover, as explained above, the optical sensor 18 can provide data regarding ambient conditions such as hue and brightness, and the control unit 14 can therefore be configured to adjust, for example, the brightness, contrast, and / or hue of the display 16 to take into account changing ambient conditions and ensure that the appearance of the displayed vision test to the user 12 remains essentially the same under changing ambient conditions.

[0091] Thus, the control unit 14 and optical sensor 18 can be used to provide improved stability of testing conditions, thereby allowing vision tests to be performed under essentially standardized conditions.

[0092] The optical vision test that may be performed on a device as part of a computer-implemented method is further described in an example embodiment according to Figures 4 and 5, which show first and second method steps for determining an indication of an initial vision level and a more refined indication of a final vision level, respectively.

[0093] Thus, as shown schematically in Figure 4, the user may be provided with a graphical display including discontinuities according to the first acuity level displayed on the display in step S100. Additionally, the display may indicate that a user response is required by allowing the user to select an indication regarding whether the user perceives the graphical display as continuous or discontinuous.

[0094] If the user response correctly identifies the discontinuity, as indicated by the arrow originating from the bottom of step S100, the control unit adjusts the vision test by displaying a further graphical representation on the display in step S110 including a discontinuity corresponding to a second acuity level and prompting the user to identify the discontinuity by providing a user response, the second acuity level being higher than the first acuity level.

[0095] If the user again correctly identifies the discontinuity according to the second visual acuity level, the method may proceed to step S112, where the method performs a step of adjusting the visual acuity test by using the control unit to display on the display a further graphical representation including a discontinuity corresponding to the previous higher visual acuity level using a predetermined amount, and notifying the user to identify the discontinuity by providing a user response.

[0096] This step may be repeated until a predetermined maximum visual acuity level is achieved, as indicated by the dashed line, controlled in step S114. If the maximum visual acuity level is achieved, the method may resolve an initial visual acuity level corresponding to the maximum visual acuity level in step S200.

[0097] If the user does not identify a second or subsequent discontinuity, as indicated by the arrows emanating from the right side of each step, further display of the graphical display having discontinuities corresponding to increasing acuity levels is also stopped. The method then continues in step S116, where the further graphical display includes a discontinuity corresponding to acuity levels lower than the previous acuity by a predetermined amount, and prompts the user to identify the discontinuity by providing a further user response.

[0098] If the user is then able to correctly identify the discontinuity, as a result, the method proceeds to step S116A, and the steps are repeated until no discontinuities are identified starting from the arrowhead from the right side of step S116A, or until the maximum visual acuity level indicated by the dashed line is reached, the discontinuity test can be performed by prompting the user to identify the discontinuity by providing a further user response, whereby the initial visual acuity level display is set to the visual acuity level corresponding to the discontinuity last displayed in step S200.

[0099] If the user does not identify a discontinuity in step S116, the steps are repeated in step S116B, with the initial visual acuity level indication set to the visual acuity level corresponding to the last discontinuity displayed in step S200, until the first visual acuity level displayed in step S100 is achieved, or until a total of two discontinuities, preferably no further discontinuities, are identified, as indicated by the arrow originating from the bottom from S116B.

[0100] Thus, steps S110 through S114 may provide a graphical display with larger acuity level differences at each discontinuity, while steps S116, S116A, and S116B provide a more defined estimate or finetuning of the rough estimate.

[0101] If in step S100 the user is unable to identify the discontinuity according to the first visual acuity level, as indicated by the arrow originating from the right side of S100, the method selects a predetermined lower limit as the visual acuity level in step S120 and sets the initial visual acuity level to the limit in step S200.

[0102] In the second step of the method shown schematically in FIG. 5, in step S500, further refinement of the initial acuity level indication resolved in step S200 is performed to resolve a final acuity level indication.

[0103] Thus, a pool of graphical representations is generated in step S400, each graphical representation including a discontinuity corresponding to a particular acuity level, the pool including a predetermined number of graphical representations having discontinuities according to the indication of the initial acuity level S200. Further, in step S300, a predetermined number of graphical representations having discontinuities corresponding to acuity levels, with a predetermined amount, are added, in a preferred embodiment, higher, or alternatively, lower, than the indicated initial acuity level S200. In one embodiment, the addition of these additional graphical representations can be based on an evaluation of the user's responses and the number of identifications of graphical representations having discontinuities corresponding to the initial acuity level indication. For example, when two or a majority of the user's responses correspond to correct identifications, the additional graphical representation can have a discontinuity corresponding to a higher acuity level than the indicated initial acuity level S200, while in the opposite situation, the acuity level is lower. However, such a pre-evaluation is merely optional. In a preferred embodiment, in step S300, a predetermined number of graphical displays having discontinuities according to the indication of the initial visual acuity level S200 and a predetermined number of graphical displays having discontinuities corresponding to higher visual acuity levels are added in response to such pre-assessment or according to a standard.

[0104] As explained above, the initial visual acuity level indication resolved in step S200 may be represented by a corresponding LogMAR value of, for example, −0.4, and three representations according to the LogMAR value may be added to the pool, and three further representations according to a LogMAR value of, for example, −0.5 may be added to the pool, i.e., optionally, generating a pool having six graphical representations in step S400 when the majority of previous user responses regarding the graphical representations corresponding to the initial visual acuity level indication are correct.

[0105] Next, in step S420, the vision test and pool are adjusted by displaying a graphical representation randomly selected from the pool, the displayed graphical representation is removed from the pool, and the user is prompted to identify the corresponding discontinuity.

[0106] If the user correctly identifies a discontinuity, a predetermined graphical representation having a discontinuity corresponding to a higher acuity level than the initial acuity level with a predetermined amount, e.g., having a -0.1 LogMAR value, may be added to the pool if a graphical representation having a discontinuity corresponding to the resulting acuity level has not already been added to the pool. For example, when the user correctly identifies a discontinuity according to a -0.5 LogMAR acuity level after the initial pool generation, at the start of the second step, a corresponding number of graphical representations having a higher acuity level, e.g., -0.6 LogMAR, are added to the pool, as indicated by the dashed line originating from the bottom of step S420 and connecting to the step of adding graphical representations in step S300.

[0107] In contrast, if the user does not identify a discontinuity, e.g., the user does not identify a discontinuity according to the graphical display according to the indication of the initial acuity level, as indicated by the dotted line beginning on the right side of step S420 and connecting to the step of adding graphical displays in step S300, when no graphical displays having discontinuities corresponding to acuity levels have already been added to the pool, a predetermined number of graphical displays having discontinuities corresponding to acuity levels lower than the initial acuity level by a predetermined amount may be added to the pool. Following this example, a corresponding number of graphical displays having lower acuity levels, e.g., about -0.3 LogMAR, are added to the pool.

[0108] These steps continue, with user responses being registered until the pool is empty in step S500, where a final visual acuity indication is resolved based on the user responses, e.g., by evaluating the user responses and determining the highest visual acuity at which the majority of the user responses correctly identified the corresponding discontinuity. Alternatively, or additionally, statistical analysis and / or averaging of the corresponding scores defined by each user response and the corresponding visual acuity level may be performed. Thus, the second step of the method provides a final visual acuity level indication so that the initial visual acuity level indication can be refined and / or confirmed, and the initial estimate of visual acuity level can be more accurately determined and fine-tuned. This may assist a physician in assessing a patient's visual acuity level and performing a diagnosis.

[0109] 4 and 5, it may be further provided that the user responses, scoring, indication of initial visual acuity level, and / or indication of final visual acuity level are stored and / or transmitted to a medical professional to obtain tracking and monitoring of the development of the user's or patient's visual acuity level or test performance, whereby, in particular, the present method facilitates administering visual acuity tests at any location, at regular or periodic intervals, and / or according to a prescribed testing schedule, so that any significant changes may be detected at an early stage without requiring the user to participate in medical treatment.

[0110] It will be apparent to those skilled in the art that these embodiments and items are merely examples of multiple possibilities. Therefore, the embodiments shown herein should not be understood to form limitations on these features and configurations. Any possible combination and configuration of the described features can be selected in accordance with the scope of the present invention.

[0111] [Code list] 10 equipment 12 users 14 Control Unit 16 Display 18 Optical Sensor 20 Graphical Display 22 Discontinuity 24 distance 26 angles 28A, B Indication S100 Display the first visual acuity level S110- S120 Determination of initial visual acuity level indication S200 Addition of initial visual acuity level or corresponding graphical display S300 Adding more graphical displays S400 Pool Generation S420 Pool Adjustment S500 Ultimate Vision Level Indication Solution

Claims

1. 1. A computer-implemented method for determining an indication of a user's visual acuity level, the method comprising: conducting an optical vision test using a control unit (14) in communication with a display (16) of the device (10), the display (16) having a predetermined resolution; and displaying the optical vision test on the display (16) of the device (10), the displayed optical vision test including a graphical representation (20) including a discontinuity (22), and prompting the user (12) to identify the discontinuity (22) by providing a user response; The optical vision test is adjusted using the control unit (14) and the display (16) by generating and displaying the discontinuities (22) based on the user response and based on anti-aliasing using one or more pixels of the display (16).

2. 2. The method of claim 1, wherein the discontinuities are aligned along a longitudinal direction of the display, a user response is received by the control unit upon selection of an indication related to the discontinuity, and the graphical display includes the indications on opposite ends of the graphical display.

3. 3. The method of claim 2, wherein the display (16) is configured as a touchscreen, and the user response is received by the control unit (14) using tactile interaction with the touchscreen in or toward an area of the display (16) corresponding to the indication (28A, 28B).

4. The method of any of claims 1 to 3, wherein the indication of the visual acuity level of the user (12) is determined based on the user response using the control unit (14).

5. 5. The method of claim 4, wherein the optical vision test is performed by the control unit (14) in two steps, in a first step an indication of an initial vision level (S200) is determined, and in a second step the indication of the initial vision level (S200) is refined and / or confirmed as an indication of a final vision level (S500).

6. 6. The method of claim 5, wherein in the first step, the graphical representation (20) includes a discontinuity (22) corresponding to a first acuity level (S100), and if the user response correctly identifies the discontinuity (22), the control unit (14) adjusts the optical vision test by displaying on the display (16) a further graphical representation (20) including a discontinuity (22) corresponding to a second acuity level (S110), and prompts the user (12) to identify the discontinuity (22) by providing a user response, the second acuity level being higher than the first acuity level, and if the user response does not identify the discontinuity (22), the control unit (14) sets the indication of the initial acuity level to a predetermined initial acuity level lower than the first acuity level (S200).

7. If the user response correctly identifies the discontinuity (22) according to the second visual acuity level, the method includes adjusting (S112) the optical visual acuity test by displaying, using the control unit (14), on the display (16) a further graphical representation (20) including a discontinuity (22) corresponding to a visual acuity level higher than the previous visual acuity level by a predetermined amount, and prompting the user (12) to identify the discontinuity (22) by providing a user response; 7. The method of claim 6, wherein step (S112) is repeated if the user response correctly identifies the discontinuity, thereby achieving the initial visual acuity level indication (S200), until a predetermined maximum visual acuity level is achieved (S114), or until the user response no longer identifies the discontinuity.

8. If the user response does not identify the discontinuity, the method further includes adjusting the optical vision test by displaying (S116) a further graphical representation (20) on the display (16) including a discontinuity (22) corresponding to a visual acuity level that is lower than a previous visual acuity level by a predetermined amount, and prompting the user (12) to identify the discontinuity (22) by providing a further user response; If further user responses do not identify the discontinuity (22), the step of adjusting the optical vision test is repeated (S116B) until a discontinuity (22) is correctly identified, until the first visual acuity level is achieved, or until a total of two subsequent discontinuities are not identified, and the indication of the initial visual acuity level is set to the visual acuity level corresponding to the last displayed discontinuity (S200); or 8. The method of claim 7, wherein if a further user response identifies the discontinuity, the method includes the steps of: displaying (S116A) on the display (16) using a control unit (14) a further graphical representation (20) including a discontinuity (22) corresponding to a visual acuity level higher than a previous visual acuity level by a predetermined amount; and adjusting the optical vision test by prompting the user (12) to identify the discontinuity by providing a further user response; and if the further user response identifies the discontinuity, the steps (S116A) are repeated (S114) until no discontinuities (22) are identified or until the maximum visual acuity level is achieved, and the indication of the initial visual acuity level is set (S200) to the visual acuity level associated with the last displayed discontinuity.

9. the displayed optical vision test comprises or consists essentially of a graphical display (20) displayed in black on a white background; and / or 9. The method of claim 1, wherein the displayed optical vision test comprises at least two lines, and wherein the adjusting comprises adjusting the size, length, and / or thickness of the lines.

10. The method further includes detecting at least a facial characteristic of the user (12) by using an optical sensor (18) of the device (10) in communication with the control unit (14); 10. The method of claim 1, wherein the control unit determines a distance between the display and the detected facial characteristics of the user based on the detected facial characteristics, and adjusts the displayed optical vision test based on the determined distance and the resolution.

11. 11. The method of claim 10, wherein an angle (26) between the display (16) and the detected facial characteristic of the user (12) is determined using the control unit (14), and the displayed optical vision test is adjusted based on the determined angle (26).

12. 12. The method of any of claims 1 to 11, wherein the displayed optical vision test is adjusted by the control unit (14) based on ambient brightness, contrast, and / or hue detected by an optical sensor (18) of the device (10) in communication with the control unit (14).

13. The method of claim 12, wherein the adjusting comprises adjusting brightness, contrast, and / or hue of the display (16).

14. 10. An apparatus (10) for determining an indication of a visual acuity level of a user (12), comprising a control unit (14) and a display (16), said apparatus (10) being configured to perform a method according to any of claims 1 to 9.

15. Further comprising an optical sensor (18) and configured to perform the method according to any one of claims 10 to 13; and / or The device (10) of claim 14, wherein the device (10) is configured as a portable and / or handheld device.

16. 16. The device (10) of claim 15, wherein the device (10) is configured as a mobile terminal and includes an integrated camera as the optical sensor (18).

17. 17. The device (10) of any one of claims 14 to 16, wherein the device (10) includes a wireless communication module, and the control unit (14) is configured to perform the optical vision test using data received from the wireless communication module and / or to transmit the determined indication of the visual acuity level to a remote device using the wireless communication module.

18. 14. The method of claim 1, wherein the graphical representation (20) comprises at least two lines arranged essentially along a longitudinal direction of the display, the discontinuities (22) being formed as offsets of the lines in a direction perpendicular to the longitudinal direction of the display (16), and the indication of the visual acuity level of the user (12) is determined based on the user response by using the control unit (14).

19. the control unit (14) adjusts the displayed optical vision test based on the detected resolution of the display (16); and / or The method of claim 18 , wherein the offset is formed as a gradient shift of the one or more pixels using the anti-aliasing.

Images