System and method for determining the rounded value of the optical characteristics of an ophthalmic lens configured to provide power correction for improving a subject's vision.

Abstract

The present invention relates to a system for determining a rounded value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision, wherein the system comprises one or more processors programmed to implement the following steps: a) a step of determining a first test value of an optical feature and a first variation increase of an optical feature (400); b) a step of performing a first eye examination of the subjective test (500), wherein two first different optical situations are determined based on at least the first test value (500); c) a step of determining a second test value of an optical feature based on the first test value, the first variation increase, and the first eye examination result (600); d) a step of performing a second eye examination of the subjective test (700), wherein two second different optical situations are determined based on at least the second test value (700); e) a step of determining an intermediate value of an optical feature based on the first eye examination result and the second eye examination result (800); f) the intermediate value as a reference value A step (900) for determining a rounded value of an optical feature by rounding, wherein the rounding is a step (900) of correcting the power of the ophthalmic lens by less than a predetermined basic power value.

Description

Technology Field

[0001] The present invention relates to a system and method for determining the rounding value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision. Background Technology

[0002] To manufacture an ophthalmic lens configured to improve a subject's vision, it is necessary to determine the optical characteristic values ​​of the said ophthalmic lens suitable for the subject. To determine these optical characteristic values, eye care professionals typically perform subjective tests on the subject using appropriate optical devices. Various literatures describe devices and methods for determining these optical characteristic values ​​of an ophthalmic lens. These optical characteristics may include, for example, sphere power, cylinder power, or the cylindrical axis.

[0003] Generally, the above subjective test comprises several steps, referred to as a trial below, during which the subject is required to compare two different optical situations considering the test values ​​of optical characteristics. Thus, the subjective test corresponds to a trial sequence. Based on the subject's feedback regarding this comparison, referred to as the subject's answer below, the eye care professional increases the test value and, in the next trial of the subjective test, provides the subject with two new different optical situations based on the increased test value. This process is repeated until the subject provides a specific answer or a combination of answers. Subsequently, the prescribed value of the optical characteristics is generally determined as a function of the test value used in the last trial of the above subjective test.

[0004] To determine the precise value of optical characteristics, the new device allows eye care professionals to use small increments between successive eye examinations of subjective tests. For example, a phoropter using a variable lens allows for increments of less than 0.2 D.

[0005] In this context, the determined optical characteristic values ​​are accurate, but they do not take into account the standard optical characteristic values ​​of ophthalmic lenses available on the market.

[0006] Ophthalmic lenses are not commercially available for virtually all values ​​of their optical characteristics. Only a set of predetermined values, referred to below as the "standard values" of each optical characteristic, is available.

[0007] In addition, devices and methods that utilize small increments between consecutive eye examinations in subjective tests generally result in long examination times and the risk that the subject may not perceive any difference between two consecutive eye examinations in the subjective test. Therefore, eye care professionals may need to shorten the test due to the subject being impatient, stressed, experiencing eye strain, or lacking attention.

[0008] Therefore, there is also a device and method that, on the one hand, enables the subject to clearly understand the subjective test, and on the other hand, reduces the test time without exceeding the accurate value of the optical feature.

[0009] Accordingly, one object of the present invention is to provide a system for determining a rounded value of an optical feature of an ophthalmic lens configured to provide a power correction for improving the visual acuity of a subject, at least, the system comprising an optical device for performing a subjective test comprising evaluating the visual performance of a subject placed in two different optical situations, and a computer comprising one or more processors programmed to implement the following steps, wherein the steps are:

[0010] a) a step of determining a first test value of an optical feature and a first variation increase of an optical feature,

[0011] b) A step of performing a first examination of the self-aware test using the optical device, wherein two first different optical situations are determined based on at least a first test value,

[0012] c) a step of determining a second test value of an optical feature based on a first test value, a first variation increase, and the first eye examination result performed in step b),

[0013] d) A step of performing a second examination of the self-aware test using the optical device, wherein two second different optical situations are determined based on at least a second test value,

[0014] e) a step of determining an intermediate value of optical features based on the first examination result performed in step b) and the second examination result performed in step d),

[0015] f) A step of determining the rounded value of the optical feature by rounding the above intermediate value to a reference value, wherein the rounding is a step of correcting the power of the ophthalmic lens by an amount less than a predetermined basic power value.

[0016] "Correcting the power correction of the above ophthalmic lens by less than a predetermined basic power value" means that between an ophthalmic lens capable of providing a value of optical characteristics identical to the intermediate value and an ophthalmic lens actually providing a rounded value of optical characteristics, the power corrections provided by these two ophthalmic lenses may differ by less than the basic power value. The "power correction" of the lens corresponds to the total optical refractive power of the lens obtained from the optical characteristics of the lens, such as spherical refractive power, cylindrical refractive power, and axis.

[0017] A reference value refers to, for example, a predetermined value of a standard. The reference value is included, for example, in a predetermined set of standard values ​​of corresponding optical features that may be used in ordering or manufacturing.

[0018] Accordingly, due to the system according to the present invention, the rounded value of an optical feature can correspond to a standard value of the optical feature. This enables obtaining a reference optical feature value that is compatible with the standard value currently applied for lens manufacturing.

[0019] The standard values ​​of this predetermined set are preferably regularly spaced discrete values. Subsequently, the basic frequency values ​​represent these regular intervals. This is substantially equal to the difference between two consecutive standard values ​​in the set of standard values.

[0020] In the examples described here, the standard value is equal to a multiple of the base power value. A multiple means that the standard value is the base power value multiplied by an integer. For example, spherical refractive powers are often prescribed and manufactured as multiples of 0.25 D.

[0021] In this context, if the intermediate value of the optical feature differs from a multiple of the predetermined basic degree value, the processor may be programmed to round the intermediate value to the nearest or second-to-nearest multiple of the predetermined basic degree value in step e).

[0022] The system according to the present invention may also take into account the personal characteristics of the subject. This provides adaptability to the system. Here, personal characteristics are, in a general manner, any characteristics related to the physical or optical conditions of the subject.

[0023] Accordingly, the processor may be additionally programmed to determine a first variation increase based on at least the subject's first personal characteristics in step a).

[0024] Increasing the variation, whereby not only the first variation but also any continuous variation increase is adapted to the subject, makes it possible to reduce, for example, the number of subjective tests performed before determining the intermediate value of optical features.

[0025] When the difference between two different optical situations is based on an increase in variation, adapting the increase in variation to the subject also prevents uncertain answers when the subject does not perceive the difference between the two optical situations.

[0026] For example, in a spherical refractive power determination test, the increase in variation may increase with the age of the subject. This may be 0.30 D for a 20-year-old subject with good vision, 0.55 D for a 50-year-old subject with myopia, and 1.30 D for an 85-year-old patient showing some lesions.

[0027] The processor may also be additionally programmed, in step f), to round the intermediate value according to a rounding method according to at least the subject's second personal characteristic or the type of self-aware test being performed. The second personal characteristic may be the same as the first personal characteristic, or another personal characteristic different from the first personal characteristic.

[0028] This allows for selection between the nearest or second-to-nearest multiples of the aforementioned predetermined base power value, for example, depending on the age of the subject. For example, the median value may be rounded to the smaller value among the nearest or second-to-nearest multiples to prevent the eyes of a young subject from becoming accustomed to the correction. The median value may be rounded to the larger value among the nearest or second-to-nearest multiples to ensure that the correction sufficiently improves visual acuity in the case of an older subject.

[0029] In another example, for a subject with myopia, the median value is preferably rounded to the smaller of the nearest or second-to-nearest multiples, whereas for a subject with hyperopia, the median value is preferably rounded to the smaller of the nearest or second-to-nearest multiples.

[0030] In the case of a subject who requires correction primarily for distant vision, for example, a professional driver, the median value is preferably rounded to the smaller value, whereas in the case of a subject who requires correction primarily for near vision, the median value is preferably rounded to the larger value between the nearest or second-to-closest multiple.

[0031] The intermediate value may also be rounded so that the difference between the rounded value and the value obtained from the subject's previous optical equipment becomes the minimum difference.

[0032] Other advantageous and non-limiting features of the system according to the present invention are as follows:

[0033] - The first personal characteristic includes at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, optical characteristics of the subject's eyes;

[0034] - Second personal characteristics include at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, optical characteristics of the subject's eyes;

[0035] - In step b), the processor is additionally programmed to determine two first different optical situations based on the first variation increase;

[0036] - The subject is placed in two different optical situations during the self-aware test by achieving at least one of the following:

[0037] - Displaying targets placed within red and green environments,

[0038] - Adding a cross cylinder in front of the subject's eyes at two different positions,

[0039] - Placing two lenses of different spherical shapes in front of the subject's eyes,

[0040] - Displaying two targets of different sizes,

[0041] - Placing different lenses in front of the subject's right and left eyes;

[0042] - Optical features include at least one of the following;

[0043] - Spherical refractive power of the above ophthalmic lens,

[0044] - Circumferential refractive power of the above ophthalmic lens,

[0045] - The circumferential axis of the above ophthalmic lens,

[0046] - Difference in spherical refractive power between two ophthalmic lenses placed in front of the right and left eyes;

[0047] - The processor is additionally programmed to implement the following steps;

[0048] g) A step of determining the current test value and the current fluctuation increase based on the results of a prior examination and the prior test value corresponding to the prior examination,

[0049] h) a step of performing a current examination of the subjective test, comprising evaluating the visual performance of the subject placed in two different current optical situations determined based on at least the current test value,

[0050] i) A step of modifying the current test value based on the current examination and the current increase in variation, and modifying the current increase in variation based on the current examination results,

[0051] and

[0052] Optionally, repeat steps h) and i), and

[0053] The processor is programmed to determine the intermediate value based on the current test value in step e);

[0054] - The processor is additionally programmed to determine the current increase in variation in step g) and / or modify it in step i) based on the degree of certainty of the results of the preceding eye examination performed;

[0055] - The current increase in fluctuation is smaller than the above-determined base frequency value;

[0056] - The processor is additionally programmed to modify the current fluctuation increase by decreasing the value of the current fluctuation increase in step i);

[0057] - The processor is additionally programmed to perform step e) above in the following cases;

[0058] - If the current test value consecutively increases and decreases or decreases and increases in the last two consecutive examinations, or

[0059] - If the second test value is greater than the first test value, and the current test value determined in step g) is smaller than the second test value, or

[0060] - If the second test value is smaller than the first test value, and the current test value determined in step g) is larger than the second test value;

[0061] - The processor is additionally programmed to perform step e) above in the following cases;

[0062] - During the final eye examination, if the subject evaluates two final, different optical situations that provide equivalent visual performance, and

[0063] - During a preliminary examination performed prior to the final examination above, if the subject evaluates one of two different preceding optical situations and it provides better visual quality than the other preceding optical situation.

[0064] The present invention also relates to a method for determining a rounded value of an optical feature of an ophthalmic lens configured to provide a power correction for improving a subject's vision, which can be executed by the aforementioned system and may include steps a) through f).

[0065] Specific explanation regarding the example(s)

[0066] The following description, made with reference to the attached drawings which should be regarded as non-limiting examples, will help in understanding the invention and how it can be realized. Brief explanation of the drawing

[0067] FIG. 1 is a schematic diagram of a system according to the present invention. FIG. 2 is a block diagram schematically showing the steps of a method for determining a rounded value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision according to the present invention, implemented by the system of FIG. 1. FIG. 3 is a schematic diagram of a first decision tree of a first examination sequence of a first subjective test aimed at determining the spherical refractive power value of an ophthalmic lens, programmed in a first embodiment of the system of FIG. 1, wherein each examination of the first subjective test includes displaying targets placed in red and green environments. FIG. 4 is a schematic diagram of a second judgment tree of a second examination sequence of a second subjective test aimed at determining the circumferential axis value of an ophthalmic lens, programmed in a second embodiment of the system of FIG. 1, wherein each examination of the second subjective test includes adding a cross cylinder in front of the subject's eye at two different positions. Figure 5 is a diagram of a user interface that can be used by an eye care professional to determine the rounded value of an optical feature. FIG. 6 is a schematic diagram of a third judgment tree of a third examination sequence of a third subjective test aimed at determining the spherical refractive power value of an ophthalmic lens, programmed in a third embodiment of the system of FIG. 1, wherein each examination of the third subjective test comprises placing two lenses of different spherical shapes in front of the subject's eye. FIG. 7 is a schematic diagram of a fourth judgment tree of a fourth examination sequence of a fourth subjective test programmed in a fourth embodiment of the system of FIG. 1, which aims to determine the spherical refractive power value of an ophthalmic lens in a relaxed accommodation state of the subject, wherein each examination of the fourth subjective test includes displaying two targets of different sizes. FIG. 8 is a schematic diagram of a fifth judgment tree of a fifth examination sequence of a fifth subjective test, programmed in a fifth embodiment of the system of FIG. 1, which aims to determine the bi-ocular balance value of two ophthalmic lenses adapted to the eyes of the subject, wherein each examination of the fifth subjective test comprises placing different lenses in front of the subject's right and left eyes. Specific details for implementing the invention

[0068] FIG. 1 illustrates a system (1) according to the present invention, comprising an optical device (2) and a computer (3).

[0069] The optical device (2) is configured to perform an examination of the self-aware test by providing two different optical situations to the subject.

[0070] As described in more detail below, the optical characteristics of ophthalmic lenses can be determined by performing different subjective tests. Each subjective test is associated with a specific optical situation provided to the subject. These optical situations, and the optical devices configured to provide them accordingly, may have different characteristics that vary depending on the optical characteristics determined through the corresponding subjective tests.

[0071] Optical features may include dioptric optical features, that is, optical features measured in diopters, or optical features representing orientation, i.e., angles, measured in degrees, for example.

[0072] Here, optical features include, for example, one or more of the following: spherical refractive power, cylindrical refractive power, cylindrical axis, and spherical difference between the right and left eyes.

[0073] To this end, a self-aware test may include one or more of the following:

[0074] - Duochrome test to determine spherical refractive power,

[0075] - Cross cylinder test to determine circumferential deflection and / or axis,

[0076] - A visual acuity test without accommodation relaxation to determine spherical refractive power,

[0077] - A visual acuity test in a relaxed state of accommodation to determine spherical refractive power,

[0078] - Binocular balance test.

[0079] Specific examples will be provided below.

[0080] Accordingly, the corresponding optical device includes the following optical means:

[0081] - An optical means for placing an ophthalmic lens having the same optical characteristics as the test value in front of the subject's eye, and simultaneously displaying a target including a sign placed in a red or green environment, therein.

[0082] - Optical means for displaying a target having multiple elements and adding cross cylinders arranged consecutively at two different positions depending on the circumferential axis test value in front of the subject's eyes,

[0083] - Optical means for displaying a target by sequentially arranging two ophthalmic lenses having the same optical characteristics and two different test values ​​(different spherical surfaces) in front of the subject's eye,

[0084] - Optical means for placing an ophthalmic lens having the same optical characteristics as the test value in front of the subject's eye and displaying two targets of different sizes,

[0085] - Optical means for simultaneously placing different examination lenses in front of the subject's right and left eyes and displaying a target for each eye.

[0086] In fact, the optical device (2) includes, for example, a phoropter equipped with an ophthalmic lens having variable optical features.

[0087] As a variation, the optical device (2) may also include a set of ophthalmic lenses having different values ​​for the optical features.

[0088] Additionally, the optical device (2) includes a device for displaying the target. The device for displaying the target may be any type of display device, such as a screen. This may include an active digital screen, such as a liquid crystal display, or a passive screen and a projection device.

[0089] Depending on the self-aware test performed, the optical device (2) may also include a cross cylinder.

[0090] The optical device (2) is described more specifically using the first to fifth self-aware tests shown in FIGS. 3, 4, 6, 7 and 8.

[0091] The computer (3) includes, for example, one or more processors and one or more memories. Here, instructions for implementing the steps illustrated in FIG. 2 for determining the rounded value of the optical features of an ophthalmic lens configured to provide a power correction for improving the vision of a subject, in particular, are stored in the one or more memories. Subsequently, the one or more processors are programmed to execute these steps.

[0092] Here, the computer (3) includes a user screen for displaying information to an eye care professional and an input device that enables the eye care professional to interact with the computer. The input device may include a keyboard, a mouse, a touch screen, voice control means, the user screen itself when the user screen is touchable, or any other known input means.

[0093] An example of a user interface displayed on a user screen is illustrated in FIG. 5, which is further explained using a second conscious test performed according to the method of the present invention.

[0094] Here, the computer (3) includes a communication device that enables the computer to be connected to the optical device (2) and to give commands thereto, for example, to give commands to the target screen of the optical device (2).

[0095] FIG. 2 illustrates a method implemented by system (1) for determining a rounded value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision.

[0096] In all embodiments of the present invention, the method comprises the following steps:

[0097] a) a step (400) of determining a first test value of an optical feature and a first variation increase of an optical feature,

[0098] b) A step (500) of performing a first examination of a self-aware test using the optical device, wherein two first different optical situations are determined based on at least a first test value,

[0099] c) a step (600) of determining a second test value of an optical feature based on a first test value, a first change increase, and a first eye examination result performed in step b),

[0100] d) A step (700) of performing a second examination of the self-aware test, wherein two second different optical situations are determined based on at least a second test value using the optical device,

[0101] e) a step (800) of determining an intermediate value of optical features based on the first examination result performed in step b) and the second examination result performed in step d),

[0102] f) A step (900) of determining a rounded value of an optical feature by rounding the above intermediate value to a reference value, wherein the rounding is a step (900) of correcting the power of the ophthalmic lens by an amount less than a predetermined basic power value.

[0103] This method is not limited to performing two eye examinations of the subjective test. In fact, the number of eye examinations of the subjective test required to determine the median value may exceed two.

[0104] The processor can be additionally programmed to implement the following steps:

[0105] g) A step (710) of determining the current test value and the current fluctuation increase based on the results of the prior examination and the prior test value corresponding to the prior examination,

[0106] h) a step (720) of performing a current examination of the conscious test, comprising evaluating the visual performance of the subject placed in two different current optical situations determined based on at least the current test value,

[0107] i) A step (730) of modifying the current test value based on the current examination result and the current increase in variation, and modifying the current increase in variation based on the current examination result,

[0108] and

[0109] Optionally, repeat steps h) and i), and

[0110] In step e), the program is configured to determine the above intermediate value based on the current test value.

[0111] In the following, the word “current” refers to any examination of the subjective test after the first and second examinations and the test value and increase in variation associated with this current examination. In step i), modification of the current test value and current increase in variation means that these two parameters are increased, updated, or adjusted.

[0112] A prior examination generally refers to any examination performed prior to the current examination. This may be a first, second, or any other examination performed prior to the current examination. In practice, the current test value and, optionally, the current increase in variation are determined based on the test value and / or increase in variation of the immediately preceding examination. This may be a second or any other examination performed prior to the current examination. However, considering the continuous nature of examinations, the current test value and the current increase in variation nevertheless depend on all prior examination test values ​​and increase in variation.

[0113] Step a)

[0114] In step 1 a), the first test value (V1) of the optical feature is determined.

[0115] The first test value may be determined based on the subject's past data, the results of previous subjective tests, or objective measurements.

[0116] The first test value can be obtained, for example, from the subject's previous optical equipment. This determination of the first test value is particularly interesting when the subject is already wearing ophthalmic lenses and when the subject wishes to change their current correction.

[0117] The first test value may also be determined based on the results of other previous subjective tests or the results of a prior eye examination of the same subjective test. The prior eye examination of the subjective test may have been performed immediately before step a) by the same eye care professional executing the method according to the present invention. Other previous subjective tests may have been performed immediately before or in the past by the same eye care professional or by a different eye care professional.

[0118] In such cases, the determination of the first test value may take into account the degree of certainty of the result of the self-aware test.

[0119] If the optical characteristic is a refractive optical characteristic, the first test value can be determined using an objective refraction test. The objective refraction test can be performed using a retinoscopic examination device or an automatic refractometer that may be included in the optical device (2). The objective refraction test can be performed by the same eye care professional who performed step a) immediately before step a). This can also be performed by a different eye care professional or may have been performed in the past.

[0120] The first test value may also be determined by an eye care expert based on the subject's individual characteristics or a combination of individual characteristics.

[0121] The personal characteristics of the above-mentioned subject may include any of the first or second personal characteristics described below.

[0122] In addition, in step 1 a), the first change increase (I1) is determined.

[0123] The first change increase (I1) may be a predetermined value that depends on the self-aware test performed in step b).

[0124] This can also be determined based on the results of other previous subjective tests or the prior eye examination results of the same subjective test.

[0125] In such cases, the determination of the first change increase may take into account the degree of certainty of the result of the above-mentioned self-aware test.

[0126] In an embodiment, the processor is programmed to determine a first variation increase (I1) based on at least a first personal characteristic of the subject in step a).

[0127] The first personal characteristic includes, for example, at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, and optical characteristics of the subject's eyes. The optical characteristics of the subject's eyes may include, for example: aberrations of the eyes, opacity of the eyes, and objectively measured optical characteristics of the eyes. The first personal characteristic may also include the subject's sensitivity, i.e., the magnitude associated with the individual's ability to perceive variations in the lens power correction.

[0128] For example, when determining spherical refractive power as in the first, third, and fourth subjective tests, in a subject with low visual acuity (e.g., 3 / 10), the first increase in variation is preferably greater than 1 D, whereas in a subject with excellent visual acuity (e.g., 12 / 10), the first increase in variation is preferably less than 0.5 D or 0.3 D.

[0129] As described below, the first fluctuation increase (I1) is used in step c) to determine the second test value (V2) used in the second examination of the self-aware test.

[0130] Preferably, the first variation increase is greater than the base degree value. The first variation increase (I1) is greater than, for example, 0.3 D or 10 degrees. This allows for rapid convergence to a test value representing the correction required by the subject. In other words, this allows for a reduction in the number of eye examinations required to determine the rounded value of the optical feature. As described more specifically below, the first variation increase (I1) used in the first eye examination of the subjective test is also preferably greater than the increase value used in the additional eye examination of the subjective test.

[0131] Step b)

[0132] Two first different optical situations are determined based on at least the first test value (V1).

[0133] After determining the first test value (V1), in step b), the first examination of the self-aware test is performed.

[0134] To this end, two first different optical conditions (S1, S2) are determined based on at least a first test value (V1) and provided to the subject by an optical device (2). During the first eye examination of the conscious test, the subject is asked to gaze at one or more targets through one or more examination lenses, and the characteristics of these examination lenses, for example, their spherical refractive power or their orientation, are based on the first test value (1). Here, the targets are displayed on the target screen of the optical device (2).

[0135] Two first different optical situations (S1, S2) may also account for the first variation increase (I1). This is, for example, the case of the third self-aware test described later.

[0136] During the first eye examination of the subjective test, the subject is asked to compare two first optical situations (S1, S2), that is, to evaluate which of the two first optical situations (S1, S2) provides superior visual performance according to the subject's perception. To obtain this information, depending on the subjective test being performed, an eye care specialist may ask, for example, "in which situation can you see the target better?" or "which target can you see better?"

[0137] The subject may not be able to clearly distinguish the target in either of the first optical situations (S1, S2). In this case, the subject evaluates which situation allows them to distinguish the target better.

[0138] The result of the subjective test consists of the subject's response, given to evaluate which of the two first optical situations (S1, S2) provides better visual quality, for example, as an answer to one of the aforementioned questions. In this way, the result may consist of one of the following three answers:

[0139] i) First Answer: The subject indicates that, among two optical situations (S1, S2), the given optical situation (S1) provides better visual quality, that is, better visual performance, than the other optical situation (S2);

[0140] ii) Second Answer: The subject indicates that among the two optical situations (S1, S2), the other optical situation (S2) provides better visual quality, that is, better visual performance, than the previously considered optical situation (S1);

[0141] iii) Third Answer: The subject indicates that the two optical situations (S1, S2) provide equivalent visual performance, or that the subject cannot select the better optical situation between the two. This final indication explains the answer "I don't know."

[0142] As a variation, the answer may be defined as follows: the first answer may be an indication that neither of the two optical situations provides good visual quality, the second answer may be an indication that both optical situations provide good visual quality, and the third answer may be an indication that one of the two optical situations provides good visual quality.

[0143] In the following, two optical situations will be indicated by the same reference numerals (S1 and S2) for each examination, even though they change from one examination to the next. The optical situation referred to by S1 in each examination is referred to as the first type of optical situation below, whereas the optical situation referred to by S2 in each examination is referred to as the second type of optical situation below. As described more specifically below, the first type of optical situation has common features or common differences with respect to the second type of optical situation.

[0144] For example, in the Duochrome test, the optical situation (S1) corresponding to the green target will be Type 1, while the optical situation (S2) corresponding to the red target will be Type 2. In the visual acuity test, the optical situation (S1) corresponding to the target with lower visual acuity or the lens with smaller spherical refractive power will be Type 1, while the optical situation (S2) corresponding to the target with higher visual acuity or the lens with larger spherical refractive power will be Type 2.

[0145] Optical situations referred to as S1 or S2 correspond to each other.

[0146] In practice, an eye care professional inputs the results of the self-examination test into a computer (3) using an input device. For example, in the user interface illustrated in FIG. 5, if the first examination result is the first answer, the eye care professional selects the left button (50), for example by clicking. If the result is the second answer, the eye care professional selects the right button (52). If the result is the third answer, the eye care professional selects the center button (51).

[0147] The dependence of the two optical conditions on the examination and test values ​​of the self-aware test, and possibly the increase in variation, is explained more specifically in the first to fifth self-aware tests illustrated in FIGS. 3, 4, 6, 7, and 8.

[0148] Step c)

[0149] In step c), a first test value (V2) of the optical feature is determined. The second test value (V2) is determined specifically based on the first test value (V1), the first variation increase (I1), and the first eye examination result of the self-aware test performed in step b).

[0150] The determination of the second test value may take into account the degree of certainty of the first examination result.

[0151] Here, the second test value (V2) is calculated as, for example, the sum of the first test value (V1) and the first change increase (I1) or the difference between them, that is, by adding the first change increase (I1) to the first test value (V1) or subtracting it from it. For example, as shown in FIG. 3, the second test value (V2) can be calculated accordingly according to the following mathematical formula (V2 = V1 ± I1), where the sign (±) indicates a + or - sign.

[0152] The second test value (V2) may also be calculated as the weighted sum of the first test value (V1) and the first variation increase (I1) or the difference between them. For example, as shown in FIG. 6, the second test value (V2) may be calculated accordingly according to the following formula (V2 = V1 ± C x I1), where C is a coefficient of actual positive values ​​including, for example, 0.1 to 5, preferably 0.5 to 2.

[0153] The first examination result determines whether the second test value (V2) is greater than or less than the first test value (V1), and accordingly determines whether the first fluctuation increase (I1) is added to or subtracted from the first test value (V1).

[0154] According to the self-assessment test, obtaining the first answer or the second answer as the first examination result, respectively, yields a second test value (V2) that is greater or smaller than the first test value (V1).

[0155] According to the self-aware test, obtaining the third answer as the result of the first examination yields a second test value (V2) that is greater or smaller than the first test value (V1). In other words, in the first examination of the self-aware test, the third answer is processed as the first or second answer.

[0156] In effect, obtaining a third answer as the result of the first examination may be considered as the subject misunderstanding the subjective test. Therefore, the second test value (V2) is also determined to be greater or smaller than the first test value (V1) after the third answer. According to the subjective test, as long as the third answer is obtained consecutively as the result of consecutive examinations, the test value increases or decreases from one examination to the next.

[0157] In a preferred embodiment, a second increase in variation (I2) is further determined, for example, based on the first eye examination result and the first increase in variation (I1). Preferably, the second increase in variation (I2) is smaller than the first increase in variation (I1); this is reduced. Also preferably, the second increase in variation (I2) may be smaller than the base frequency value.

[0158] As a variation, the second fluctuation increase is greater than the base frequency value. This enables the performance of a rapid self-aware test.

[0159] The determination of the second increase in variation may take into account the degree of certainty of the first examination result.

[0160] Step d)

[0161] In step d), two second different optical situations, one of the first type (S1) and one of the second type (S2), are determined based on the second test value (V2), and the second examination of the self-aware test is performed using these second different optical situations.

[0162] The second examination of the above-mentioned subjective test is similar to the first examination. The second examination of the subjective test is different from the first examination only in that the two different optical situations (S1, S2) provided to the subject vary according to the second test value (V2) and do not vary according to the first test value (V1).

[0163] In the same way as the first examination, two second different optical situations (S1, S2) can also consider the second variation increase (I2).

[0164] During the second examination of the subjective test, the subject is asked to compare two second optical situations and evaluate which of the two second optical situations provides better visual performance. The result of the second examination is also the first, second, or third answer provided by the subject.

[0165] The first answer corresponds to a subject indicating that among the two second optical situations, the first type of second optical situation (S1) provides better visual performance, the second answer corresponds to a subject indicating that among the two second optical situations, the second type of second optical situation (S2) provides better visual performance, and the third answer corresponds to a subject indicating that the two second optical situations (S1, S2) provide equal visual performance or that one of the two second optical situations cannot be selected as the better optical situation.

[0166] Step g)

[0167] The aforementioned first and second examinations may actually correspond to two initial examinations performed when starting the examination sequence of the self-aware test. These may correspond to any two consecutive examinations in the examination sequence.

[0168] More generally, during each examination of a subjective test, the subject is asked to compare two second current optical situations, one of type 1 (S1) and one of type 2 (S2), and evaluate which of the two current optical situations provides better visual performance.

[0169] Accordingly, the ulterior step of the method according to the present invention is described below in a more general manner.

[0170] In step g), the current test value (VC) is determined. The current test value (VC) is determined by considering the preceding test value and the preceding eye examination results of the subjective test. Here, the current test value (VC) is also determined by considering the increase in preceding variation.

[0171] The previous test value, previous increase in variation, and previous examination correspond to the immediately preceding test value, increase in variation, and examination below. This may be the second test value, second increase in variation, and second examination.

[0172] As all test values ​​are determined by taking into account the preceding test values ​​and the results of the preceding examination, the current test value is determined by taking into account the second examination result of the self-aware test performed in step d), particularly the second test value (V2), and the second increase in variation (I2).

[0173] The current test value (VC) is calculated, for example, as the sum of the previous test value (VP) and the previous change increase (IP) or the difference between them. Accordingly, the current test value (V2) can be calculated according to the following mathematical formula (VC = VP ± IP).

[0174] The current test value (VC) can also be calculated as the weighted sum of the previous test value (VP) and the previous change increase (IP), or as the difference between them. Thus, the current test value (VC) can be calculated according to the following formula (VC = VP ± C x IP), where C is a real positive coefficient, for example, from 0.5 to 2.

[0175] The previous eye examination result of the subjective test determines whether the current test value (VC) is greater or smaller than the previous test value (VP).

[0176] In fact, according to the self-aware test, the first answer (where the subject indicates a first type of optical situation (S1)) and the second answer (where the subject indicates a second type of optical situation (S2)) each yield a current test value (VC) that is greater or smaller than the previous test value (VP).

[0177] Based on the subjective test and previous examination results, the third answer derives the calculation of the current test value (VC) or the determination of a direct median value (VI). More precisely, the third answer derives a direct determination of the median value (VI) if the preceding examination result is the first or second answer.

[0178] In addition, the current increase in variation (IC) can be determined, for example, based on the results of a previous self-awareness test and the previous increase in variation.

[0179] Here, the processor may be additionally programmed to determine the current increase in variation (IC) and / or the current test value based on the degree of certainty of the prior examination performed, preferably the result of the previous examination.

[0180] In a general manner, to consider the degree of certainty of the subject, certainty data indicating the degree of certainty of the subject is collected when providing the first, second, or third answer, recorded in one or more of the aforementioned memories, and linked to the corresponding answer for each eye examination of the conscious test. Here, the degree of certainty is determined as in the document US 2019261848. Accordingly, the certainty data may be based on a measurement of the duration used by the subject to provide his answer while looking at the target, or other measurements by a sensor, such as a pressure sensor associated with a button used by the subject to record his answer. Any means known to those skilled in the art may be used.

[0181] For example, if the current test result is the first or second answer or is uncertain—that is, if the degree of certainty is below a predetermined threshold—the increase in variability is preferably reduced. In effect, this means that the current test value is close to the correction required by the subject.

[0182] If the degree of certainty is high, the first or second answer may be processed as the third answer.

[0183] Step h)

[0184] Two different current optical conditions, one of the first type (S1) and one of the second type (S2), are determined based on at least the current test value (VC).

[0185] The current examination of the subjective test is performed by providing the subject with two current optical situations.

[0186] The current examination is similar to the first and second examinations.

[0187] In the same manner as the first and second examinations, two different current optical situations (S1, S2) can also be determined based on the second current increase (IC).

[0188] During the present examination of a subjective test, the subject is asked to compare two present optical situations and evaluate which of the two present optical situations provides better quality vision. The present examination result is also the first, second, or third answer provided by the subject.

[0189] Step i)

[0190] After step h), the updated test value (VCup) is determined by modifying the current test value (VC) based on the current eye examination result of the self-aware test and the current change increase (IC) in step i).

[0191] Here, the updated current test value (VCup) after correction is calculated, for example, as the sum of the current test value (VC) and the current change increase (IC) or the difference between them. Accordingly, the updated current test value (VCup) can be calculated according to the following mathematical formula (VCup = VC ± IC).

[0192] In fact, the first and second answers each derive an increase or decrease in the current test value (VC), that is, an updated current test value that is smaller or larger than the current test value.

[0193] Based on the subjective test and the results of the first subjective and second optometry tests, the third answer derives an increase or decrease in the current test value (VC), that is, a determination of an updated current test value greater than or less than the current test value, or a direct determination of the median value (VI). More precisely, the third answer derives a direct determination of the median value (VI) if the result of the preceding optometry test (i.e., the first, second, or current optometry) is the first or second answer.

[0194] After modifying the current test value, that is, after calculating the updated current test value (VCup), the current change increase (IC) is modified based on the current examination result.

[0195] The updated test value (VCup) is considered as the current test value in the next current examination.

[0196] In the same manner as the determination of the current test value, the processor may be additionally programmed to modify the current increase in variation based on the degree of certainty of the aforementioned prior examination result.

[0197] Here, preferably after several repetitions of step h) and step i), for example, 1 to 4 repetitions, the current increase in fluctuation is smaller than the predetermined basic frequency value.

[0198] In this way, the current test value (VC) can have lower precision than the base frequency value. Therefore, the current test value can accurately represent the correction required by the subject. Consequently, the intermediate value (VI) determined in step e) also accurately represents the correction required by the subject.

[0199] As a variation, the current increase in variability can be greater than the base frequency value. This enables the performance of a rapid self-aware test.

[0200] In an embodiment, the processor is additionally programmed to modify the current fluctuation increase by decreasing the value of the current fluctuation increase in step i).

[0201] This also enables the determination of a very precise current test value (VC), that is, a current test value with greater precision than the basic frequency value.

[0202] If the following first or second interruption condition occurs, the processor interrupts the repetition of steps h) and i) or does not perform them at all. In other words, if such an interruption condition occurs, the processor immediately performs step e).

[0203] The first interruption condition occurs in the following cases:

[0204] - During the final examination of the subjective test, that is, while the examination is being performed for the last time, if the subject evaluates two final, different optical situations and provides equivalent visual performance, i.e., if the final examination result is a third answer, and

[0205] - During the preliminary examination of the subjective test performed prior to the final examination above, if the subject evaluates one of two different preceding optical situations and provides a better visual quality than the other preceding optical situation, i.e., if the final examination result is the first or second answer.

[0206] The final test of the self-aware test is here the second examination or any alternative current examination. The preceding examination may be any examination performed before the final examination. Here, the preceding examination is, more specifically, a previous examination performed immediately before the final examination.

[0207] If the first interruption condition occurs, it means that the test value tested during the final examination accurately indicates the correction required by the subject.

[0208] The second interruption condition occurs in the following cases:

[0209] - If the current test value consecutively increases and decreases or decreases and increases in the last two consecutive examinations, or

[0210] - If the second test value is greater than the first test value, and the current test value determined in step g) is smaller than the second test value, or

[0211] - When the second test value is smaller than the first test value, and the current test value determined in step g) is larger than the second test value.

[0212] For example, if three consecutive examinations referred to as the first, second, and current examinations are performed, the second interruption condition may occur in the following cases:

[0213] - If the updated current test value is greater than the current test value and the current test value is less than the second test value, or

[0214] - When the updated current test value is smaller than the current test value and the current test value is larger than the second test value.

[0215] The second interruption condition allows the median value (VI) to be determined sooner (i.e., by performing fewer examinations) than waiting solely for the occurrence of the first condition. In practice, this means that the median value (VI) can be determined even when the third answer is not provided—that is, even when the correction required by the patient is not tested as a test value during the examination.

[0216] In this case, the determined median value (VI) is included between the two last test values. For example, here, the median value (VI) is determined as the average between the two last test values. This allows determining the median value (IC) that indicates the correction required by the subject.

[0217] Step e)

[0218] In step e), the median value (VI) of the optical feature is determined based on the results of the first and second ophthalmic test values ​​performed in steps b) and d).

[0219] As described above, depending on the results of the first and second examinations, step e) may be performed immediately after step d). In this case, only the first and second examinations are performed.

[0220] For example, this is the case where the first discontinuation condition occurs after the second examination.

[0221] In this case, the median value (VI) is the same as the second test value (V2).

[0222] As previously mentioned, depending on the results of the first and second examinations, step e) may be performed immediately after step g). In this case, only the first and second examinations are performed.

[0223] For example, this is a case where a second suspension condition occurs after the determination of the current test value in step g), that is, when the second test value is greater than the first test value and the current test value determined in step g) is less than the second test value, or when the second test value is less than the first test value and the current test value determined in step g) is greater than the second test value, and the intermediate value (VI) can be calculated as the average between the current test value and the second test value.

[0224] If additional examination is implemented, the current test value (VC) and the current fluctuation increase are determined, and the determination of the median value (VI) is also based on the current test value (VC) and the current fluctuation increase (VI).

[0225] If additional examination is implemented, the median value (VI) may be, for example, equal to the last test value or calculated as the average between two last test values.

[0226] For example, if the current test value increases and decreases or decreases and increases in the last two consecutive tests, that is, in the last two implementations of step h) and step i), the median value (VI) can be calculated as the average between the two last current test values.

[0227] For example, if the current examination result is the third answer, the median value (VI) can be determined to be the same as the current test value.

[0228] Step f)

[0229] After determining the intermediate value (VI), the rounded value of the optical feature is determined by rounding the intermediate value (VI) relative to the reference value.

[0230] Rounding is performed so that the power correction of the ophthalmic lens is adjusted to be less than a predetermined base power value.

[0231] If the optical characteristic is a degree optical characteristic, this means that the difference between the rounded value and the median value is smaller than the base degree value.

[0232] When the optical feature is the cylindrical axis, this means that the difference in orientation between the rounded value and the intermediate value is perceived by the subject as a change in cylindrical refractive power smaller than the base power. In fact, as is well known in the field of cylindrical lenses, a change in the orientation of the cylindrical axis results in a change in cylindrical refractive power. Consequently, a correction of the cylindrical axis can be recorded as a correction of cylindrical refractive power.

[0233] Therefore, when the optical characteristic is the cylindrical axis, adjusting the power correction of the ophthalmic lens by less than a predetermined base power value means that the change in cylindrical refractive power resulting from the change in the cylindrical axis is smaller than the predetermined base power value.

[0234] For example, if the circumferential refractive power is less than 1.5 D, the axis can be rounded to a multiple of 5 degrees. On the other hand, if the circumferential refractive power is greater than 1.5 D, rounding to a multiple of 5 degrees can result in a circumferential refractive power change greater than 0.25 D. Therefore, if the circumferential refractive power is greater than 1.5 D, the intermediate value is preferably rounded to a multiple of 2 degrees.

[0235] The observed change in power also depends on the circumferential refractive power of the test lens itself.

[0236] The base power value can be determined by an eye care professional based on the precision of the prescription to be delivered. The base power value is, for example, 0.25 D.

[0237] As previously mentioned, the reference value is the standard value used in the manufacture of ophthalmic lenses. Here, if the optical feature is a power optical feature, the reference value is defined more precisely as a multiple of the basic power value. If the optical feature is a circumferential axis, the reference value is defined as a multiple of a given angle, for example, 5 degrees.

[0238] Here, when the optical feature is a degree optical feature, one or more processors of the optical device (2) are programmed more precisely to round the intermediate value of the optical feature to the nearest or second nearest multiple of the predetermined basic degree value when the intermediate value of the optical feature differs from the multiple value of the predetermined basic degree value.

[0239] For example, if the median value (VI) determined in step e) is 0.87 D and the base frequency value is 0.25 D, the nearest or second nearest multiples are 0.25 D, 0.75 D, and 1 D. The median value (VI) may be rounded accordingly to 0.75 D or 1 D.

[0240] In the same way, when the optical feature is a circumferential axis, one or more processors of the optical device (2) are programmed more precisely to round the intermediate value of the optical feature to the nearest or second nearest multiple of the given angle if the intermediate value of the optical feature differs from the multiple value of the given angle.

[0241] For example, if the median value (VI) determined in step e) is 17 degrees and the base degree value is 5 degrees, the multiples of 5 degrees closest to or second closest to 17 degrees D are 15 degrees and 20 degrees; the median value (VI) can be rounded to 15 degrees or 20 degrees.

[0242] Here, the processor is also additionally programmed to round the intermediate value (VI) according to a rounding method based on at least the subject's second personal characteristics or the type of self-aware test being performed.

[0243] Second personal characteristics include, for example, at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, optical characteristics of the subject's eyes;

[0244] For example, in subjects whose age exceeds the threshold value, the median value (VI) is preferably rounded to the larger of the nearest or second-closest value, whereas in subjects whose age is below the threshold value, the median value (VI) is preferably rounded to the smaller of the nearest or second-closest value.

[0245] Next, in the example where the median value (VI) determined in step e) is 0.87 D, for older subjects, the median value (VI) is preferably rounded to a larger value, i.e., 1 D, whereas for younger subjects, the median value (VI) is preferably rounded to a smaller value, i.e., 0.75 D.

[0246] According to other examples, the median value may be rounded to the smaller of the nearest or second-closest multiples in subjects who have visual acuity superior to a given threshold value and / or have no complaints regarding their visual performance or current vision equipment and / or have no specific lesions, have low visual needs, and have no activities requiring improved vision. The median value may be rounded to the larger of the nearest or second-closest multiples in subjects who have visual acuity lower than a threshold value and / or have complaints regarding their visual performance or current vision equipment and / or have specific lesions and / or have high visual needs and / or have activities requiring improved vision.

[0247] Five subjective tests, each comprising an eye examination sequence, are now described with reference to FIGS. 3 through 8. The eye examination sequence includes all steps a) through f) of the method according to the present invention, thereby enabling the determination of a rounded value of an optical feature. Hereinafter, if the test value is determined as the sum of the previous test value and the previous increase in variation, it is said to be increased. Conversely, if the test value is determined as the difference between the previous test value and the previous increase in variation, it is said to be decreased.

[0248] Here, the first answer corresponds to an indication that, in most of the described examples, the first type of optical situation (S1) provides better visual performance than the other, the second answer corresponds to an indication that the second type of optical situation (S2) provides better visual performance than the other, and the third answer corresponds to an indication that both types of optical situations (S1, S2) provide equivalent visual performance.

[0249] As a variation described for the example related to the fourth subjective test, the first answer may correspond to an indication that neither of the two optical situations provides good quality vision, the second answer may correspond to an indication that both optical situations provide good quality vision, and the third answer may correspond to an indication that one of the two optical situations provides good quality vision.

[0250] The first and second answers will be indicated in the drawing by reference numerals of the corresponding optical situations (S1, S2). The third answer will be indicated in the drawing by reference numeral (M).

[0251] In FIGS. 3, FIGS. 4, FIGS. 6, FIGS. 7, and FIGS. 8, a common reference numeral is used for the first, second, and third answers.

[0252] 1st Awareness Test

[0253] The judgment tree of the sequence of the first self-aware test is shown in Fig. 3.

[0254] In this first subjective test, the optical characteristic of the ophthalmic lens is spherical refractive power.

[0255] Each eye examination includes displaying two targets, each containing a sign placed within a red and green environment, and providing the subject with an eye examination lens having an eye examination spherical refractive power value.

[0256] This subjective test is often known as the "Duochrome test." Here, this subjective test is a monocular test. The rounded value is determined for one eye. The sequence can be performed a second time or in parallel for the other eye. In the case of such parallel performance, the first subjective test may accordingly be a binocular test.

[0257] The target is displayed on the target screen of the optical device (2).

[0258] In a first type of optical situation (S1), the first of the two targets includes a sign displayed on a uniform green background. The sign includes, for example, an optotype or a geometric shape.

[0259] In a second type of optical situation (S2), the second target among the two targets includes a sign displayed on a uniform red background. The sign includes, for example, a visual target or a geometric shape. The second sign may be the same as the first sign.

[0260] During each eye examination, the subject is asked to look at two targets through an eye lens having the same spherical refractive power as the test value, and to identify which target shows a sign more clearly.

[0261] In step a) indicated by reference numeral (100) in FIG. 3, the first test value may be determined, for example, as the subject's current correction or based on objective or subjective measurements.

[0262] In the first examination, the spherical refractive power value of the examination lens is the same as the first test value (V1).

[0263] If the subject sees the sign more clearly on a green background than on a red background, the first examination result is the first answer (110). Optionally, this means that the spherical refractive power value of the examination lens is insufficient to provide adequate correction for the test subject's eye. Accordingly, this is increased in the next examination. In step d) indicated by reference numeral (10) in FIG. 3, the second test value (V2) is then determined as the sum of the first test value (V1) and the first variation increase (I1).

[0264] If the subject sees the sign more clearly on a red background than on a green background, the first examination result is the second answer (120). Optionally, this means that the spherical refractive power of the examination lens is strong and does not provide adequate correction for the test subject's eye. Accordingly, this is reduced in the next examination. In step d) indicated by reference numeral (20) in FIG. 3, the second test value (V2) is then determined as the difference between the first test value (V1) and the first variation increase (I1).

[0265] More generally, if the examination result is the first answer (110, 221, 211, 231), the test value increases, and if the examination result is the second answer (120, 222, 212, 232), the test value decreases.

[0266] If the subject sees the sign equally clearly against a green and red background, the first examination result is the third answer (130). Optionally, this means that the spherical refractive power of the examination lens is appropriate.

[0267] However, as previously mentioned, obtaining a third answer as the first examination result is considered to be a misunderstanding of the test by the subject. Here, in this case, in step d) indicated by reference numeral (30), the second test value (V2) is also determined as the sum of the first test value (V1) and the first variation increase (I1), that is, as the first examination result is the first answer.

[0268] As long as the continuous examination result is the third answer (233), the test value is determined as the sum of the previous test value and the increase in the previous fluctuation, i.e., it is increased.

[0269] Here, the median value (VI) and the corresponding rounded value are found as the smaller spherical refractive power (diopter) that provides equally sharp signs in two optical situations (S1, S2). Consequently, a second answer (a sharper sign against a red background) must be obtained before determining the median value. In effect, this is the only answer that ensures the ophthalmic spherical refractive power value is smaller than the appropriate value for the subject's visual correction. This also enables the prevention of the subject's accommodation, which could bias the determination of the median value.

[0270] This is the reason why all branches of the decision tree illustrated in Fig. 3 that derive the decision of the median value (VI) include the second answer (212, 120, 232) at one point.

[0271] The median value (VI1) is determined, for example, when two consecutive examination results are the first answer (110, 211, 231) followed by the second answer (212). In this case, the median value (VI1) is equal to the current test value (VC), which is determined as the difference between the previous test value (V2) and the previous increase in variation (I2) in step g) or step i) indicated by reference numeral (11) in FIG. 3, where the previous increase in variation (I2) is equal to half of the preceding increase in variation (I1). The current test value (VC) is accordingly the average between the two preceding test values ​​(V2, V1). This case corresponds to the second interruption condition.

[0272] The median value (VI2) can also be determined when two consecutive examination results are the first answer (120, 222) and then the first answer (221). In this case, the median value (VI2) is equal to the current test value (VC'), which is determined as the sum between the previous test value (V2') and the previous increase in variation (I2') in step g) or step i) indicated by reference numeral (21) in FIG. 3, where the previous increase in variation (I2') is equal to half of the preceding increase in variation (I1). This case also corresponds to the second interruption condition.

[0273] The median value (VI3) can also be determined when two consecutive examination results are the second answer (120, 222) followed by the third answer (223). In this case, the median value (VI3) is the same as the previous test value (V2') determined in step c), step g), or step i). This case corresponds to the first interruption condition.

[0274] Finally, the median value (VI4) can also be determined when two consecutive examination results are the third answer (130, 233, 213) followed by the second answer (232). In this case, the median value (VI4) is equal to the current test value (VC) which is determined as the difference between the previous test value (V2) and the previous increase in variation (I2) in step g) or step i) indicated by reference numeral (31) in FIG. 3, where the previous increase in variation (I2) is equal to the preceding increase in variation (I1).

[0275] Preferably, between the first and last examinations of the sequence, the increase in variation is reduced. Preferably, this is reduced from one examination to the next. For example, the first increase in variation (V1) is equal to 1 D, and the second increase in variation (V2) is equal to 0.3 D.

[0276] In another example, the current increase in variation is calculated as the value of the increase in variation of the preceding examination, preferably the previous examination, multiplied by a coefficient strictly less than 1. Subsequently, the current increase in variation is preferably smaller than the base power value. The base power value is, for example, 0.25 D.

[0277] In this first sequence, at step f), the rounding value is determined by rounding the median value to the nearest or second-to-closest multiple of the base frequency value. As previously mentioned, the rounding method may vary depending on the individual characteristics of the subject.

[0278] 2nd Awareness Test

[0279] The judgment tree of the second self-aware test is illustrated in Fig. 3.

[0280] This second subjective test is often known as the "cross cylinder." This implies placing a cross cylinder in front of the subject's eyes at two different positions, that is, in two different orientations. This subjective test is a monocular test. The rounded value is determined for one eye. The sequence can be performed a second time for the other eye.

[0281] In this example of the second self-perceptual test, the optical feature is the circumferential axis. However, the circumferential refractive power can be determined using a similar self-perceptual test with a similar judgment tree.

[0282] During each eye examination, the subject is asked to look at a target displayed, for example, on the target screen of an optical device (2), through an eye examination lens known as a “Jackson cross cylinder” and referred to as a cross cylinder in this invention.

[0283] In the first type of optical situation (S1), the cross cylinder is arranged in the first orientation.

[0284] In the second type of optical situation (S2), the cross cylinder is arranged in a second orientation. Here, the second orientation is the result of a 90-degree rotation relative to the first orientation, centered on the eye's gaze axis, and accordingly, the positive and negative axes of the cross cylinder are interchanged.

[0285] Here, the positive axis is defined as the axis where the refractive power of the cross cylinder is maximum, for example, +0.25 D or +0.5 D. The negative axis is defined as the axis where the refractive power of the cross cylinder is minimum, for example, -0.25 D or -0.5 D.

[0286] When determining the circumferential axis, in each examination, the cross cylinder is positioned with respect to the examination circumferential axis value. Here, the examination circumferential axis value is an angle (degree) with respect to a predetermined direction, e.g., the horizontal direction. In the first type of optical situation (S1), the positive axis of the cross cylinder is oriented counterclockwise at 45 degrees from the examination circumferential axis value, and in the second type of optical situation (S2), the positive axis of the cross cylinder is oriented clockwise at 45 degrees from the examination circumferential axis value.

[0287] In the first examination, the examination circumferential axis value is the same as the first test value. In the second examination, the examination circumferential axis value is the same as the second test value. In the current examination, the examination circumferential axis value is the same as the current test value.

[0288] In FIG. 5, the value of the examination cylinder axis is shown as a letter (A) indicated by reference numeral (53). In FIG. 5, the value of the examination cylinder axis is the same as in FIG. 17. The cross cylinder is shown by a circle indicated by reference numeral (54). The positive axis of the cross cylinder proceeds through the two first poles (55) of the cross cylinder, and the negative axis of the cross cylinder proceeds through the two second poles (56) of the cross cylinder.

[0289] For the subject, the target viewed through the cross cylinder appears indistinct in both optical situations (S1, S2). During the subjective test, the eye care specialist may ask, "In which situation does the target appear less blurry?"

[0290] Therefore, if the examination result is the first answer (110, 221, 211, 231), the test value increases, and if the examination result is the second answer (120, 222, 212, 232), the test value decreases.

[0291] Unless all preceding examination results are the third answer, if the result is the third answer (213, 223), the median value (VI1, VI5) is subsequently determined to be the same as the last test value (V2, V2"). This corresponds to the first cessation condition.

[0292] As in the first subjective test, obtaining a third answer as the first examination result is considered that the subject has misunderstood the subjective test. Here, in this case, the second test value (V2') is determined as the sum of the first test value (V1) and the first variation increase (I1), that is, as the first examination result is the first answer.

[0293] As long as the continuous examination result is the third answer (233), the test value is determined as the sum of the previous test value and the increase in the previous fluctuation, i.e., it is increased.

[0294] As in the first subjective test, the intermediate value (VI2, VI4) is determined, for example, when two consecutive eye examination results are followed by the first answer (110, 211, 231) and the second answer (212), or conversely, when the second answer (120, 222) and the first answer (221) are followed. In this case, the intermediate value (VI2, VI4) is equal to the current test value (VC, VC"), which is determined as the difference between the previous test value (V2, V2") and the previous change increase (I2, I2") or as the sum thereof, respectively, where the previous change increase (I2, I2") is equal to half of the preceding change increase (I1). This case corresponds to the second interruption condition.

[0295] Finally, the median value (VI3) can also be determined when two consecutive examination results are the third answer (130, 233) followed by the second answer (232). In this case, the median value (VI3) is equal to the current test value (VC'), which is determined as the difference between the previous test value (V2') and the previous increase in variation (I2'), where the previous increase in variation (I2') is equal to the preceding increase in variation (I1).

[0296] Preferably, between the first and last examinations of the sequence, the increase in variation is reduced. Preferably, this is reduced from one examination to the next. For example, the first increase in variation (V1) is equal to 15 degrees, and the second increase in variation (V2) is equal to 7 degrees. Subsequently, the current increase in variation may begin to become smaller than the base degree value. The base degree value is, for example, 5 degrees.

[0297] In this second sequence, at step f), the rounded value may be determined by rounding the median value to the nearest or second-to-nearest multiple of the given angle. Here, the median value is preferably rounded to the smaller of the nearest or second-to-nearest multiple of the given angle. As previously mentioned, the rounding method may vary depending on the individual characteristics of the subject.

[0298] The cylindrical refractive power of an ophthalmic lens configured to provide power correction for the subject's vision can also be determined. The judgment tree illustrated in FIG. 4 is also applied to the determination of the cylindrical refractive power. When determining the cylindrical refractive power, the test value is the power value. In each eye examination, the cross cylinder is oriented with respect to a predetermined cylindrical axis. Here, in a second type of optical situation (S2), the negative axis of the cross cylinder is aligned with the negative axis of the cylindrical axis.

[0299] Here, the cross cylinder has an examination circumferential refractive power value. In the first examination, the examination circumferential refractive power value is the same as the first test value. In the second examination, the examination circumferential refractive power value is the same as the second test value. In the current examination, the examination circumferential refractive power value is the same as the current test value.

[0300] The first test value (V1) is, for example, + 0.25 D or - 0.25 D.

[0301] In the first type of optical situation (S1), when the subject sees the target more clearly, that is, when they have better visual performance, the test value and, accordingly, the circumferential refractive power value increase. In the second type of optical situation (S2), when the subject sees the target more clearly, that is, when they have better visual performance, the test value and, accordingly, the circumferential refractive power of the cross cylinder decrease.

[0302] The first increase in variation may vary depending on the difference between the circumferential refractive power value obtained from the subject's previous optical equipment and the first test value; the greater the difference, the greater the increase in variation.

[0303] The circumferential axis and refractive power are one way to represent the circumference, but other representations exist, such as the J0 and J45 representations as described in EP 2018061207. The decision tree illustrated in Fig. 4 is also applied to the J0 and J45 representations, for example, by setting J45 to a determined value and finding J0, then setting J0 to the found value and finding J45.

[0304] Third self-awareness test

[0305] The judgment tree of the third self-aware test is shown in Fig. 6.

[0306] In this third subjective test, the determined optical characteristic is spherical refractive power. The test consists of placing two lenses of different spherical shapes in front of the subject's eyes. This subjective test is a monocular test. A rounded value is determined for one eye. This subjective test can be performed a second time for the other eye.

[0307] In a first type of optical situation (S1), the subject sees a target displayed, for example, on a target screen of an optical device (2), through a first ophthalmic lens. The first ophthalmic lens is characterized by a first ophthalmic spherical refractive power value.

[0308] In a second type of optical situation (S2), the subject views the same target through a second ophthalmic lens. The second ophthalmic lens is characterized by a second ophthalmic spherical refractive power value that is different from the spherical refractive power value of the first ophthalmic lens.

[0309] During each eye examination, the subject is asked to continuously view a target through the first eye examination lens and then through the second eye examination lens.

[0310] Here, the intermediate value (VI) and the rounded value accordingly are found as the smaller spherical refractive power (diopter) that provides equally sharp targets in two optical situations (S1, S2).

[0311] In step a) indicated by reference numeral (100) in FIG. 3, the first test value may be determined, for example, as the subject's current calibration or based on objective measurements.

[0312] During a self-assessment test, an eye care specialist may ask, "In what situations do text appear clearer?"

[0313] In the first examination, the first examination spherical refractive power value is equal to the first test value (V1) minus the first increase in variation. The second examination spherical refractive power value is equal to the first test value.

[0314] More generally, in each examination, in the first type of optical situation, the first examination spherical refractive power value is equal to the test value minus the increase in variation, and in the second type of optical situation, the second examination spherical refractive power value is equal to the test value.

[0315] In each eye examination, the first eye examination lens may be provided before or after the second eye examination lens.

[0316] If the subject sees the target more clearly with the first examination lens than with the second examination lens, the examination result is the first answer. Optionally, this means that the spherical refractive power of the second examination lens is strong and does not provide adequate correction for the test subject's eye. If the first examination result is the first answer (110), in step d) indicated by reference numeral (10) in FIG. 6, the second test value (V2') is subsequently determined to be the difference between the first test value and the first variation increase (I1), i.e., the same as the first examination spherical refractive power value.

[0317] If the subject sees the target more clearly with the second examination lens than with the first examination lens, the first examination result is the second answer. Optionally, this means that the spherical refractive power of the second examination lens is insufficient to provide adequate correction for the test subject's eye. If the first examination result is the second answer (120), in step d) indicated by reference numeral (10) in FIG. 3, the second test value is subsequently determined as the weighted sum of the first test value (V1) and the first variation increase (I1). More precisely, the second test (V2) is determined as the sum of the first test value (V1) and the first variation increase (I1) weighted by a coefficient (C) of 1 or less. For example, the weighting coefficient (C) is equal to 0.625. More generally, if the examination result is the first answer (110, 221, 211, 231), the test value decreases, and if the examination result is the second answer (120, 222, 212, 232), the test value increases.

[0318] When the subject sees the target equally clearly in both optical situations (S1, S2), the first examination result is the third answer (130).

[0319] However, as previously mentioned, obtaining a third answer as the first examination result is considered to be a misunderstanding of the test by the subject. Here, in this case, in step d) indicated by reference numeral (30), the second test value (V2") is also determined as the difference between the first test value (V1) and the first variation increase (I1), that is, as the first examination result is the first answer.

[0320] As long as the result of a series of tests is the third answer (233), the test value is determined as the difference between the previous test value and the previous increase in variation, i.e., it is reduced.

[0321] Here, to help the subject understand the subjective test, that is, to help the subject see the difference between the first optical situations (S1, S2), the first variation increase (I1) is large, for example, greater than 0.35 D.

[0322] If the first test result is the third answer (130) and the second test result is the second or third answer (232), the current test value (VC') is calculated as the sum of the second test value (V2") and the second change increase (I2"). In this case, the second change increase (I2") is greater than the first change increase (V1). For example, the second change increase (I2") is 1.625 times greater than the first change increase (I1).

[0323] Except for this specific branch of the judgment tree, the increase in variation between the first and last examinations of the sequence is preferably reduced.

[0324] If the result is the third answer (223, 212, 300), the second ophthalmic lens provides appropriate correction for the test subject's eye. Subsequently, the median value (VI1, VI3, VI5) is determined to be the same as the current test value (V2, V2', VC'), i.e., the second ophthalmic spherical refractive power value. This corresponds to the first suspension condition. The only exception is a branch where the first ophthalmic result is the third answer (130) and the second ophthalmic result is also the third answer (232).

[0325] As in the first and second sequences, the intermediate value (VI2, VI4) is determined, for example, when two consecutive eye examination results are followed by the first answer (110, 211, 231) and the second answer (212), or conversely, when the second answer (120, 222, 232, 302) and the first answer (221, 301) are followed. In this case, the intermediate value (VI2, VI4) is the same as the current test value (VC, VC).

[0326] Preferably, between the first and last examinations of the sequence, the increase in variation is reduced. Preferably, this is reduced from one examination to the next. For example, the first increase in variation (V1) may be greater than 1 D, and the second increase in variation (V2) may be less than 1 D. Subsequently, the current increase in variation may begin to become smaller than the base frequency value. The base frequency value is, for example, 0.25 D. In this third subjective test, in step f), the rounding value is determined by rounding the median value to the nearest or second-to-closest multiple of the base frequency value. As previously mentioned, the rounding method may vary depending on the individual characteristics of the subject.

[0327] 4th Awareness Test

[0328] The judgment tree of the sequence of the fourth self-aware test is shown in Fig. 7.

[0329] In this first subjective test, the optical characteristic of the ophthalmic lens is spherical refractive power.

[0330] Each eye examination involves displaying two targets of different sizes and providing the subject with an eye examination lens having an eye examination spherical refractive power value.

[0331] These subjective tests are often known as "fogging / defogging tests." These subjective tests are monocular tests. The rounded value is determined for one eye. The sequence can be performed a second time for the other eye.

[0332] In the first type of optical situation (S1), the subject views the first target through the second ophthalmic lens. The size of the first target corresponds to the first visual acuity value when viewed from the subject's observation distance.

[0333] In the second optical situation (S2), the subject sees a second target that is smaller than the first target through the same examination lens. The size of the second target corresponds to the second visual acuity value when viewed from the subject's observation distance.

[0334] During each eye examination, the subject is asked to look at two targets through an eye lens having the same spherical refractive power as the test value, and to identify which target shows a sign more clearly.

[0335] The two targets are, for example, lines of letters on a visual acuity chart. For example, in the first examination, the first target is the line of 4 / 10 and the second target is the line of 8 / 10. The first and second targets may vary from one examination to the next.

[0336] Here, during an optional initial part of the sequence (not shown in FIG. 7), the sizes of the first and second targets may be increased until the subject can clearly read at least the first target.

[0337] Here, if the subject cannot clearly read the characters of either the first or second target, the examination result is the first answer. If the subject can clearly read the characters of both the first and second targets, the examination result is the second answer. If the subject can clearly read the characters of the first target but cannot clearly read the characters of the second target, the examination result is the third answer.

[0338] Here, in step 1 a), the first test value may be determined, for example, as the subject's current correction, or based on adding, for example, a determined power value greater than 1 D to an objective or subjective measurement. Adding such a determined power value corresponds to the initial fogging step. In effect, in the first part of the sequence, fogging allows the subject's accommodation to be relaxed.

[0339] Next, as long as the subject can clearly read the second target, that is, as long as the continuous examination result is the second answer (130), the test value is increased. As illustrated in FIG. 7, when the first examination result is the second answer (120), the second test value is calculated as the sum of the first test value (V1) and the first variation increase (I1) in step c) indicated by reference numeral (20) in FIG. 7.

[0340] This increase in the test value corresponds to the first part of the sequence: the fogging phase. Here, during the fogging phase, the increase in fluctuation is preferably kept constant.

[0341] Subsequently, when the subject can clearly read the first target, that is, at the moment when the examination result is the third answer, the test value is reduced. For example, in FIG. 7, when the second examination result is the third answer (223), the current test value (VC) is calculated as the difference between the second test value (V2) and the second variation increase (I2) in step g) indicated by reference numeral (21).

[0342] The first decrease in the test value is the start of the second part of the sequence: the defogging step. Here, at the start of the second part of the sequence, the second target is set to a line corresponding to a predetermined high visual acuity, for example, visual acuity 10 / 10.

[0343] Next, as long as the subject can clearly read only the first target, that is, if the continuous examination result is the third answer (300), the test value is reduced.

[0344] Here, during the defogging phase, the increase in variation is preferably reduced from one eye examination to the next.

[0345] Next, if the subject can clearly read the second target, that is, if the examination result is the second answer (301), the median value (VI) is determined to be the same as the current test value (VC). When the second answer is obtained as the second target corresponding to the predetermined desired visual acuity, the median value is determined to be the same as the current test value.

[0346] In step f), the rounding value is determined by rounding the median value to the nearest or second-to-closest multiple of the base frequency value. The base frequency value is, for example, 0.25 D. As previously mentioned, the rounding method may vary depending on the individual characteristics of the subject.

[0347] 5th Awareness Test

[0348] The judgment tree of the fifth self-aware test is shown in Fig. 8.

[0349] In this fifth subjective test, the determined optical characteristic is the difference in spherical refractive power between the right and left eyes. The test consists of placing two lenses of different spherical shapes in front of each of the subject's eyes.

[0350] This subjective test is a binocular test. Rounding values ​​are determined for both eyes. In a first type optical situation (S1), the subject looks with his left eye at a target displayed, for example, on a target screen of an optical device (2), through a left examination lens. The left examination lens is characterized by a left examination spherical refractive power value.

[0351] In the second type of optical situation (S2), the subject views the same target with his right eye through the right examination lens. The right examination lens features a right examination lens spherical refractive power value that is different from the left examination lens spherical refractive power value.

[0352] During each eye examination, the subject is asked to sequentially view a target with his left eye through the left eye examination lens and then with his right eye through the right eye examination lens. A mask may be placed in front of one eye so that the subject can view the target with only the other eye.

[0353] Here, the median value (VI), and the rounded value accordingly, is found as the difference between the left spherical refractive power value and the right spherical refractive power value, which provides a target that is equally clear to both eyes.

[0354] In step a) indicated by reference numeral (100) in FIG. 3, the first test value may be determined as the difference in spherical refractive power between the right eye and the left eye, for example, based on the subject's current correction or based on two objective monocular measurements (one for the right eye and one for the second eye).

[0355] During a self-assessment test, an eye care specialist may ask, "In what situations do text appear clearer?"

[0356] In the first examination, the spherical refractive power value of the left eye is equal to the spherical refractive power previously determined in the monocular test for the left eye plus the determined power value (here 0.5 D), and the spherical refractive power value of the right eye is equal to the spherical refractive power previously determined in the monocular test for the right eye plus the determined power value.

[0357] When the subject sees the target more clearly with the left eye lens than with the right eye lens, that is, with the left eye, the examination result is the first answer. When the first examination result is the first answer (110), in step d) indicated by reference numeral (10) in FIG. 8, the second test value (V2) is subsequently determined as the sum of the first test value (V1) and the first variation increase (I1). This means that the difference between the left eye lens spherical refractive power value and the right eye lens spherical refractive power value increases in the second examination.

[0358] When the subject sees the target more clearly with the right eye, that is, with the right eye, than with the left eye lens, the examination result is the second answer. When the first examination result is the second answer (120), in step d) indicated by reference numeral (20) in FIG. 8, the second test value (V2') is subsequently determined as the difference between the first test value (V1) and the first change increase (I1). This means that the difference between the left eye spherical refractive power value and the right eye spherical refractive power value is reduced in the second examination.

[0359] Preferably, the left spherical refractive power value and the right spherical refractive power value are corrected symmetrically by the same amount. For example, if the difference between the left spherical refractive power value and the right spherical refractive power value increases by 0.3 D, the larger of the two is increased by 0.15 D and the smaller of the two is decreased by 0.15 D.

[0360] Here, both the left spherical refractive power value and the right refractive index value cannot be smaller than a threshold value. This threshold value is, for example, -0.05 D. For example, if the difference between the left spherical refractive power value and the right spherical refractive power value needs to be increased by 0.3 D, and the smaller value is equal to 0 D, the smaller value is reduced to -0.05 D and the larger value is reduced by 0.25 D.

[0361] More generally, if the examination result is the first answer (110, 221, 211, 231), the test value increases, and if the examination result is the second answer (120, 222, 212, 232), the test value decreases.

[0362] When the subject sees the target equally clearly in both optical situations (S1, S2), the first examination result is the third answer (130).

[0363] However, as previously mentioned, obtaining a third answer as the first examination result is considered to be a misunderstanding of the test by the subject. Here, in this case, in step d) indicated by reference numeral (30), the second test value (V2") is also determined as the difference between the first test value (V1) and the first variation increase (I1), that is, the first examination result is the second answer.

[0364] As long as the result of a series of tests is the third answer (233), the test value is determined as the difference between the previous test value and the previous increase in variation, i.e., it is reduced.

[0365] Preferably, between the first and last examinations of the sequence, the increase in variation is preferably reduced.

[0366] Unless all preceding examination results are third answers, if the result is third answer (213, 223), the median value (VI1, VI3) is determined to be the same as the last test value (V2, V2'). This corresponds to the first cessation condition.

[0367] As in the second subjective test, the intermediate value (VI2, VI4) is determined, for example, when two consecutive eye examination results are followed by the first answer (110, 211, 231) and the second answer (212), or conversely, when the second answer (120, 222) and the first answer (221) are followed. In this case, the intermediate value (VI2, VI4) is equal to the current test value (VC, VC'), which is determined as the difference between the previous test value (V2, V2') and the previous change increase (I2, I2') or as the sum thereof, respectively, where the previous change increase (I2, I2') is equal to half of the preceding change increase (I1). This case corresponds to the second interruption condition.

[0368] Finally, the median value (VI5) can also be determined when two consecutive examination results are the third answer (130, 233) followed by the first answer (231). In this case, the median value (VI5) is equal to the current test value (VC) which is determined as the sum of the previous test value (V2) and the previous increase in variation (I2) where the previous increase in variation (I2) is equal to half of the preceding increase in variation (I1).

[0369] Preferably, between the first and last examinations of the sequence, the increase in variation is reduced. Preferably, this is reduced from one examination to the next. For example, the first increase in variation (V1) may be greater than 1 D, and the second increase in variation (V2) may be less than 1 D. Subsequently, the current increase in variation may begin to become smaller than the base power value. The base power value is, for example, 0.25 D.

[0370] In this fifth sequence, at step f), the rounding value is determined by rounding the median value to the nearest or second-to-closest multiple of the base frequency value. As previously mentioned, the rounding method may vary depending on the individual characteristics of the subject.

[0371] In a well-known manner, sequences related to different subjective tests may be performed sequentially. For example, the sequence of the fifth subjective test is preferably performed after the sequence of the fourth subjective test has been performed twice, once for the left eye and once for the right eye.

[0372] In the aforementioned example of the subjective test, the rounded value is determined at the end of the examination sequence of each subjective test.

[0373] When a series of subjective tests are performed, that is, when several different subjective tests are performed consecutively, the determination of the rounded value of the optical feature to be found can be performed at the end of the examination sequence of each subjective test or at the end of all subjective tests.

[0374] In this last case, the value of the accurate and unrounded optical feature determined through a previously performed self-aware test can be used in a subsequent self-aware test. In fact, the value of the accurate and unrounded optical feature determined through the previously performed self-aware test corresponds to the aforementioned intermediate value.

[0375] In practice, when determining the cylindrical axis refractive power and cylindrical power of a cylindrical ophthalmic lens, if a subjective test is performed to determine the cylindrical power, an intermediate value representing the cylindrical axis is preferably considered.

[0376] The rounded value of the two intermediate values ​​determined by the self-recognition test for determining the circumferential axis and circumferential refractive power can be rounded after both self-recognition tests are performed. In this way, the determination of the intermediate value representing the circumferential refractive power becomes more accurate because such a determination considers the intermediate value of the circumferential axis and not its rounded value.

[0377] In a variation example, when a series of self-tests are performed, only the last intermediate value determined in the last sequence can be rounded. The preceding series of self-tests can only serve to determine the accurate first test value.

[0378] For example, if only the spherical difference between the right eye and the left eye is to be found, the fifth subjective test is preferably performed in step a), using the median value determined in the first or fourth subjective test for the left eye and the median value determined in the first or fifth subjective test for the left eye.

Claims

Claim 1 At least, a system (1) for determining a rounded value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision, wherein the system (1) comprises an optical device (2) for performing a subjective test including evaluating the visual performance of the subject placed in two different optical situations (S1, S2), and a computer (3) including one or more processors programmed to implement the following steps: a) a step (400) of determining a first test value (V1) of the optical feature and a first variation increase (I1) of the optical feature; b) a step (500) of performing a first eye examination of the subjective test using the optical device (2), wherein two first different optical situations (S1, S2) are determined based on at least the first test value (V1); c) the first test value (V1), the first variation increase (I1), and the first eye examination result (110, 120, ) performed in step b). 130) a step (600) of determining a second test value (V2, V2', V2") of the optical feature based on the optical device (2), d) a step (700) of performing a second examination of the conscious test using the optical device (2), wherein two second different optical situations (S1, S2) are determined based on at least the second test value (V2, V2', V2"), e) a step (800) of determining an intermediate value (VI1, VI2, VI3, VI4, VI5) of the optical feature based on the first examination result (110, 120, 130) performed in step b) and the second examination result (211, 212, 213, 221, 222, 223, 231, 232, 233) performed in step d), f) the intermediate value (VI1, VI2, VI3, VI4, VI5) A step (900) for determining the rounded value of the optical feature by rounding VI5) to a reference value, wherein the rounding is a step (900) of correcting the power correction of the ophthalmic lens by an amount less than a predetermined basic power value.System (1). Claim 2 In claim 1, the processor is programmed to round the intermediate value (VI1, VI2, VI3, VI4, VI5) of the optical feature to the nearest or second nearest multiple of the predetermined basic frequency value in step f) when the intermediate value (VI1, VI2, VI3, VI4, VI5) of the optical feature is different from the multiple value of the predetermined basic frequency value, system (1). Claim 3 In claim 1 or 2, the processor is additionally programmed to determine the first variation increase (I1) based on at least the first personal characteristic of the subject in step a). System (1). Claim 4 In paragraph 3, the first personal characteristic comprises at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, and optical characteristics of the subject's eyes, system (1). Claim 5 A system (1) wherein, in claim 1 or 2, the processor is additionally programmed to round the intermediate values ​​(VI1, VI2, VI3, VI4, VI5) according to a rounding method according to at least the second personal characteristics of the subject or the type of self-aware test performed in step f). Claim 6 In paragraph 5, the second personal characteristic comprises at least one of the following data regarding the subject: age, type of refractive error, visual acuity, dissatisfaction with his / her visual performance or current vision correction equipment, past data including the subject's current correction, lesions, visual needs or activities, selected eyeglass frames, selected ophthalmic lenses, and optical characteristics of the subject's eyes, system (1). Claim 7 In claim 1 or 2, the system (1) is additionally programmed to determine the two first different optical situations (S1, S2) based on the first variation increase (I1) in step b). Claim 8 A system (1) that is placed in two different optical situations (S1, S2) during a conscious test, wherein, in accordance with claim 1 or 2, the subject: - displaying targets placed within a red and green environment; - adding cross cylinders in front of the subject's eyes at two different positions; - placing two lenses of different spherical shapes in front of the subject's eyes; - displaying targets of two different sizes; - placing different lenses in front of the subject's right and left eyes; by achieving at least one of these. Claim 9 A system (1) comprising, in accordance with claim 1 or 2, at least one of the optical features: - spherical refractive power of the ophthalmic lens, - cylindrical refractive power of the ophthalmic lens, - cylindrical axis of the ophthalmic lens, - difference in spherical refractive power between two ophthalmic lenses positioned in front of the right and left eyes. Claim 10 In claim 1 or 2, the processor comprises: g) a step (710) of determining a current test value (VC, VC', VC") and a current change increase (IC) based on a prior examination result (211, 212, 213, 221, 222, 223, 231, 232, 233, 300, 301, 302) and a prior test value (V1, V2, V2', V2", VC, VC', VC") corresponding to the prior examination; h) a step (720) of performing a current examination of the subjective test, comprising evaluating the visual performance of the subject placed in at least two current different optical situations (S1, S2) determined based on the current test value (VC, VC', VC"); i) the current examination result (211, 212, 213, 221, 222, A system (1) is additionally programmed to implement the step (730) of modifying the current test values ​​(VC, VC', VC) based on the current fluctuation increase (IC) and the current test values ​​(223, 231, 232, 233, 300, 301, 302), and modifying the current fluctuation increase (IC) based on the current test results (211, 212, 213, 221, 222, 223, 231, 232, 233, 300, 301, 302); optionally, steps h) and i) are repeated, and the processor is programmed to determine the intermediate values ​​(VI1, VI2, VI3, VI4, VI5) based on the current test values ​​(VC, VC', VC) in step e). Claim 11 In claim 10, the processor is additionally programmed to determine the current variation increase (IC) in step g) and / or modify it in step i) based on the degree of certainty of the results of the prior examination performed (211, 212, 213, 221, 222, 223, 231, 232, 233, 300, 301, 302), system (1). Claim 12 In item 10, the above current fluctuation increase (IC) is smaller than the above predetermined basic frequency value, system (1). Claim 13 In claim 10, the processor is additionally programmed to modify the current fluctuation increase (IC) by decreasing the value of the current fluctuation increase (IC) in step i). System (1). Claim 14 In claim 10, the processor is additionally programmed to perform step e) when: - the current test value (VC, VC', VC") is continuously increased and decreased or decreased and increased in the last two consecutive tests; or - the second test value (V2, V2', V2") is greater than the first test value (V1) and the current test value (VC, VC', VC") determined in step g) is less than the second test value (V2, V2', V2"); or - the second test value (V2, V2', V2") is less than the first test value (V1) and the current test value (VC, VC', VC") determined in step g) is greater than the second test value (V2, V2', V2"). Claim 15 A system (1) that, in claim 1 or 2, is additionally programmed to perform step e) if: - during a final examination, the subject evaluates two final different optical situations (S1, S2) and provides equivalent visual performance; and - during a prior examination performed prior to the final examination, the subject evaluates one of two different prior optical situations (S1, S2) and provides better visual quality than the other prior optical situation (S1, S2). Claim 16 A method for determining a rounded value of an optical feature of an ophthalmic lens configured to provide power correction for improving a subject's vision, comprising: a) a step (400) of determining a first test value (V1) of the optical feature and a first variation increase (I1) of the optical feature; b) a step (500) of performing a first eye examination of a subjective test using an optical device (2), wherein two first different optical situations (S1, S2) are determined based on at least the first test value (V1); c) a step (600) of determining a second test value (V2, V2', V2") of the optical feature based on the first test value (V1), the first variation increase (I1), and the first eye examination results (110, 120, 130) performed in step b); and d) using the optical device (2), wherein two second different optical situations (S1, S2) are determined based on at least the second test value (V2, A method comprising: a step (700) of performing a second eye examination of the above-mentioned subjective test determined based on V2', V2"); e) a step (800) of determining an intermediate value (VI1, VI2, VI3, VI4, VI5) of the above-mentioned optical feature based on the first eye examination result (110, 120, 130) performed in step b) and the second eye examination result (211, 212, 213, 221, 222, 223, 231, 232, 233) performed in step d); f) a step of determining a rounded value of the above-mentioned optical feature by rounding the intermediate value (VI1, VI2, VI3, VI4, VI5) to a reference value, wherein the rounding is a step of correcting the power correction of the above-mentioned ophthalmic lens by an amount less than a predetermined basic power value.

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