Eye cone cell protection filter

Abstract

The present invention relates to a filter and related methods dedicated to protecting cone cells in the eye, the cone cell protecting filter being intended to be applied to a transparent surface to filter incident light to protect the cone cells in a user's eye from damage caused by exposure to said user's eyes at physiological light levels, and having spectral characteristics that i) filter light wavelengths in the range of 405-465 nm, and ii) transmit filtered light directed to cone cells and that is below a predetermined maximum threshold of harmfulness to said cone cells.

Description

Technical Field

[0001] The present invention generally relates to the field of eye cone cell protection filters intended for application to a transparent surface such as glasses (e.g., sunglasses) to filter incident light. Multiple embodiments of the present invention relate to a method for determining the configuration of an eye cone cell protection filter intended for application to at least one transparent surface.

Background Art

[0002] The electromagnetic spectrum covers a wide range of wavelengths, among which there are wavelengths visible to the human eye, often called the visible spectrum, ranging from 380 nm to 780 nm. Some of the electromagnetic spectrum wavelengths including those of the visible spectrum have adverse effects, while other wavelengths are known to have beneficial effects on the eye. Some wavelengths of the visible spectrum are also known to induce a range of neuroendocrine, physiological, and behavioral responses known as non-image-forming (NIF) responses.

[0003] The vertebrate retina is a photosensitive tissue arranged along the inner surface of the eyeball. The tissue has four main layers from the choroid to the vitreous humor. That is, the retinal pigment epithelium (hereinafter referred to as "RPE"), the photoreceptor layer (including rods and cones), the inner granular layer consisting of bipolar cells and Müller cells and amacrine cells, and finally, the ganglion cell layer including astrocytes, displaced amacrine cells, and some essentially photosensitive ganglion cells (1 - 3% of retinal ganglion cells). This last cell type is important for circadian (biological rhythm) and pupil function.

[0004] Nerve signals are generated in rods and cones and undergo complex processing by other neurons in the retina. The output from the processing takes the form of action potentials of retinal ganglion cells whose axons form the optic nerve. Some important features of vision can be traced back to the encoding and processing of light by the retina.

[0005] Photobiology is the study of the biological effects of light, and it has been established that a portion of the electromagnetic spectrum has beneficial effects on health, including vision and circadian functions. However, the importance of protecting the eyes from harmful irradiations such as ultraviolet (UV) light has also been established. Visible light, even at normal daily intensities, can cause cumulative retinal damage or contribute to retinal aging, and can be a worsening factor in the development of age-related macular diseases (ARM) such as early and late age-related macular degeneration (AMD). There are indications in some epidemiological studies that exposure levels to sunlight may be related to the progression of AMD.

[0006] Eyewear devices that filter out harmful UV irradiations with low spectral selectivity are widely used. For example, transparent spectacle lenses have been designed to provide UV protection by protecting the eyes from the harmful effects of UVA and UVB light. Intraocular lenses (IOLs) with UV filters were introduced in the 1990s and are mainly implanted after cataract surgery to replace the crystalline lens.

[0007] Blue light filtering solutions, including daily protection for transparent lenses with a cyan filtering level of approximately 20%, already exist. However, these solutions are based on investigations of the harmfulness of light to other types of retinal cells (RPE), and most of the research has been on higher irradiance levels of greater harmfulness. For example, previous studies on RPE (Arnault et al., 2013, PlosOne) have shown that light levels approximately three times higher are required to induce strong harmfulness to in vitro RPE cells compared to in vitro cones. As an example, approximately 1.09 mW / cm at 440 nm was used to induce 65% damage to in vitro primary RPE cells, while 0.39 mW / cm at 440 nm was used to induce 85% damage to in vitro primary cone cells. 2 was used, while 85% damage to in vitro primary cone cells was induced with 0.39 mW / cm at 440 nm. 2It was not necessary. The blue-violet light filter is designed to reduce the transmission in the specific blue RPE harmful band, i.e., the range of 415 - 455 nm, by about 20% in the case of a smart blue filter, for example, while ensuring optimal transparency for daily use. Existing blue-violet filters are mainly used as transparent lenses to prevent cumulative retinal damage on a daily basis, but do not target specific cone protection that requires a higher filtering rate.

[0008] Filters dedicated to protecting the RPE can be found in U.S. Patent No. 8,360,574, European Patent No. 2602654, and European Patent No. 2602655. In fact, those skilled in the art know that blue light can damage the RPE. Nevertheless, the research on the effect of light on cones is not yet sufficient and has been associated with visual pigments, especially green light. The light levels required to damage cones have not been evaluated.

Summary of the Invention

Problems to be Solved by the Invention

[0009] Such known solutions are not optimized for protecting cone cells from the harmfulness of light, especially blue light. Recent studies by the inventor have shown that blue light can damage cone cells by causing a higher cone cell death rate at low light irradiances than on the RPE. Also, damage by green light has not been confirmed, suggesting that the harmfulness of light to cones is something other than visual pigments and is actually present in the blue-violet range of the solar spectrum towards the retina. Photoreceptors are damaged by light, and this light-induced damage is usually considered to be due to the activation of visual pigments.

[0010] Furthermore, there is no method or solution that provides a filter specifically designed and adapted to filter light for cone cell protection. Therefore, there is a particular need to protect cone cells from the harmfulness of light.

[0011] Therefore, in view of the background art, an invention that can protect cone cells from the harmfulness of blue light is needed.

[0012] The present invention aims to improve this situation.

[0013] The present invention aims to provide a cone cell protection filter, which is applied to at least one transparent surface and filters the incident light on the transparent surface, intended to protect the user's cone cells from damage caused by irradiation at physiological light levels to the user's eyes, and has the following spectral characteristics. - Filtering light wavelengths in the range of 405 to 465 nanometers, - Transmitting filtered light that travels towards the cone cells and has a harmfulness to the cone cells below a predetermined maximum threshold value.

[0014] In this way, the cone cell protection filter may have spectral characteristics including a filtering peak in the range of 425 to 445 nm.

[0015] In fact, the harmfulness of light to cone cells reaches its maximum value at wavelengths in the range of 425 to 445 nm (as will be explained below).

[0016] Since the present invention aims to protect the user's cone cells from the harmfulness of light, the present invention probably needs to be applied to any transparent surface.

[0017] The at least one transparent surface may be the transparent surface of glasses, spectacles, sunglasses, goggle glasses, virtual reality glasses or contact lenses, intraocular lenses or ophthalmic medical devices. The at least one transparent surface may be a window, a windshield, a screen, the transparent surface of a roof, or any transparent surface for the purpose of protecting from external light. Preferably, the at least one surface is the transparent surface of glasses. The light traveling towards the cone cells may be sunlight or any artificial light, such as light from a light bulb, neon, smartphone, computer or automobile headlights.

[0018] Irradiation at physiological light levels refers to the light to which the user's eye cone cells are exposed in real life.

[0019] The filter may be an active filter or a passive filter adapted to be applied to any transparent surface as described above.

[0020] As used herein, the term "filter" refers to and encompasses the term "eye cone cell protection filter" and may be either a passive or an active filter unless the nature of the filter is specified.

[0021] The eye cone cell protection filter can partially block blue light having a wavelength in the range of 405 - 465 nm, preferably 425 - 445 nm.

[0022] According to one aspect of the present invention, there is provided an eye cone cell protection filter including an active matrix for filtering incident light on the transparent surface, and the eye cone cell protection filter further includes the following. - An input for receiving a measurement value of the light transmitted between the transparent surface and the eye, - Calculating the spectral characteristics of the eye cone cell protection filter based on at least, * The measurement value of the transmitted light, * The predetermined maximum threshold value, and a processor for controlling the active matrix to filter the incident light based on the calculated spectral characteristics.

[0023] Thus, the eye cone cell protection filter may have spectral characteristics including a filtering peak in the range of 425 - 445 nm, and the active matrix includes an electrochromic material.

[0024] As used herein, an "active filter" may be a filter capable of changing its filtering spectrum in real time by an active matrix. For example, the active matrix may include a chemical composition that reacts with light to change its filtering spectrum with respect to the amount of light received by the active filter. The active matrix may also be a chemical composition associated with an electrical system capable of converting electrical energy into the chemical composition to change the filtering spectrum of the active matrix and thus adapt the filtering spectrum in real time. Finally, the active matrix may be a filter including electrical components capable of adjusting the filtering spectrum in real time, particularly.

[0025] For example, the active filter may be an LCD active matrix, a polarization active matrix, more preferably an active matrix including an electrochromic material.

[0026] According to another aspect of the present invention, there is provided an eye cone cell protection filter applied as a passive filter. For example, the passive filter may be an absorptive filter, a dye, a polarization filter, a MOF, a photonic crystal, an interference filter using a high-index deposition, a low-index material, a photochromic lens, a cholesteric layer, or a combination of these solutions.

[0027] Preferably, the passive filter may be a light-shielding paint applied to a transparent surface and configured to absorb a certain portion of incident light.

[0028] As used herein, a "passive filter" may be a filter completely characterized by its filtering spectrum. Once the passive filter is manufactured, its filtering spectrum cannot be easily changed.

[0029] The eye cone cell protection filter may be configured to absorb more than 99% of the incident light at wavelengths below the critical wavelength.

[0030] Thus, the critical wavelength may be in the range of 425-445 nm.

[0031] The predetermined maximum threshold value may be determined based on at least one of the following elements. - The type of user activity (e.g., labor, running, swimming, cycling, horseback riding, hunting, fishing, walking), - The user's physiological parameters (e.g., the user's own filtering ability, weight, height, eye shape, angle between the frame and the face, frame shape, lens shape), - The user's age, - The average amount of light to which the user is exposed.

[0032] The predetermined maximum threshold value may be a percentage from 0 to 20%. In a preferred embodiment, no damage to the eye cone cells should be tolerated. Therefore, the predetermined maximum threshold value must be near 0%. The predetermined maximum threshold value thus represents a threshold value at which the harmfulness to the eye cone cells caused by the filtered light directed towards the eye cone cells does not reach.

[0033] Recent research by the inventors has shown that light with an average irradiance on the corneal surface ranging from 400 to 500 nm of 12 mW / cm 2 is already extremely harmful to in vitro cones, especially at wavelengths in the range of 425 to 445 nm where the cone cell death rate is close to 90%.

[0034] In the graph of FIG. 7, the two curves show that the eye cone cells are more sensitive than the RPE cells. Using the curve RPE, the harmfulness of light to the RPE cells described in Arnault et al., 2013, PlosOne has been confirmed. Recently, the harmfulness of light to the cone cells has been confirmed using the curve Cones. For example, it can be seen that at 430 nm, the harmfulness of light to the cone cells is approximately three times higher than that to the RPE cells.

[0035] In another embodiment, a predetermined maximum threshold can be determined as an example according to the average irradiance on the corneal surface over 405 - 465 nm, preferably 425 - 445 nm, obtained on a typical cloudy winter day in Paris where the harmfulness to the cones is not assumed. The predetermined maximum threshold may thus represent an irradiance threshold that the filtered light reaching the eye cone cells must not exceed.

[0036] More generally, the predetermined maximum threshold may be determined to further limit the irradiance to 0.2 mW / cm of the light directed towards the cells of the eye, preferably the eye cone cells. In this case, it would be preferable for the eye cone cell protection filter to include an active matrix. 2

[0037] Furthermore, the present invention intends to provide a method for calculating the spectral characteristics of an eye cone cell protection filter, which includes the following steps in one embodiment where, for example, an active matrix can be used. a) Obtaining the light risk (LHC) to the cone cells, defined by the eye cone cell death rate relative to the amount of sunlight incident light, for the sunlight incident light and within at least one predetermined wavelength range; b) Measuring the irradiance of the current transmitted light between the transparent surface and the eye within the above - mentioned predetermined wavelength range, and estimating the current cell death risk based on the measured value of the transmitted light; c) When the current cell death risk exceeds a predetermined maximum threshold, calculating the spectral characteristics to attenuate the measured transmitted light, and repeating steps b) and c) until the current cell death risk is below the above - mentioned predetermined maximum threshold.

[0038] In one embodiment where, for example, a passive filter can be used, it is intended to provide a method for calculating the spectral characteristics of an eye cone cell protection filter, which includes the following steps. a’) Obtaining the light risk (LHC) to the cone cells, defined by the eye cone cell death rate relative to the amount of sunlight incident light, for the sunlight incident light and within at least one predetermined wavelength range; ​b’) estimating the amount of light entering the eye based on the user's data within the above-specified wavelength range and over a specified time range; c’) estimating the current cell death risk within the above-specified time range based on the estimated amount of light; d’) when the current cell death risk exceeds the above-specified maximum threshold, calculating the above spectral characteristics to reduce the current transmitted light until the current cell death risk falls below the above-specified maximum threshold.

[0039] In any embodiment where an active or passive filter can be used, the current transmitted light can be determined in a plurality of continuous wavelength ranges, and the current cell death risk can be given by the sum of the values obtained by multiplying the current transmitted light irradiance in each of the wavelength ranges by the light risk for the cone cells.

[0040] Thus, the light risk for the cone cells can be given by the sum of the cone cell death rates relative to the solar irradiance in each of the continuous wavelength ranges. Solar irradiance refers to all light that can reach the eyeball, for example, diffuse light, reflected light, and multiply diffused or multiply reflected light added to the light from transparent surfaces or other surrounding surfaces that have passed through the transparent surface.

[0041] For example, in embodiments where other than an active matrix is also used, the spectral characteristics can be given by the following equation using the light transmittance Tlens(λ) defined for each of the continuous wavelength ranges (λ). Tlens = TH / CD, where - TH is a specified maximum threshold, - CD is the current cell death risk.

[0042] More generally, the cone cell death rate relative to the solar irradiance can be obtained from tests by calcein staining at 440 nm with an irradiance of 0.39 mW / cm 2 over 15 hours for a plurality of continuous wavelength ranges.

[0043] The present invention also aims at a computer program for calculating the spectral characteristics of a cone cell protection filter in an embodiment using an active matrix, and the computer program includes instruction codes for executing the method according to the embodiment using an active lens when the instructions are executed by the above processor.

[0044] The first computer program can be executed by a computer module MOD1 connected to an active filter 40 (for example, an electrochromic cell) of an active lens, as shown in the example of the embodiment of FIG. 2. The module MOD1 may include the following. - An input interface IN for receiving ambient light data detected by the sensor 20, - A processor PROC1 capable of cooperating with a memory unit MEM1 that stores the first computer program (and at least the above-mentioned user data serving as a basis for calculating a threshold value) to execute the first computer program and then process the data received from the sensor 20 to send a control signal to an output interface OUT, - An output interface OUT for controlling the active filter 40.

[0045] Therefore, the present invention also aims at an apparatus including a computer module MOD1 for implementing the method according to the embodiment using an active matrix.

[0046] The present invention also aims at another computer program for calculating the spectral characteristics of a cone cell protection filter in an embodiment using a passive filter, and the computer program includes instruction codes for executing the method according to the embodiment using a passive lens when the instructions are executed by the above processor.

[0047] The second computer program can be executed by a computer module MOD2 of a server SER (as shown in FIG. 10) connected via a network NET to computer devices PCH1, PCH2, ... of medical staff who send user data of future wearers to the server SER. The module MOD2 of the server SER may include the following. - A communication interface COM for receiving user data, - A processor PROC2 that executes the second computer program and then processes the user data received from the interface COM, and is capable of cooperating with a memory unit MEM2 that stores the second computer program to calculate the spectral characteristics of a passive filter for a passive lens worn by the user according to an embodiment using a passive lens.

[0048] Therefore, the present invention also aims at a server including a computer module MOD2 for implementing a method according to an embodiment using a passive lens.

Means for Solving the Problems

[0049] Therefore, according to the present invention, it becomes possible to provide a cone cell protection filter dedicated to protecting eye cone cells. In fact, the present invention discloses a method for providing a filter having a filtering spectrum that takes into account ambient light, user activities, and pathology to protect the cone cells of the above-mentioned user from the harmfulness of blue light even in situations where the light dose is low. Furthermore, the present invention takes into account the fact that cone cells are more sensitive than RPE, and thus require dedicated protection with a filtering level higher than that of filters of the prior art and below a specific light intensity threshold among specific wavelengths.

[0050] Also, the disclosure of this specification relates to isolated cone cells that do not present an aging model in any case. Therefore, the disclosure of this specification may relate to any user of any age. In particular, the disclosure of this specification may relate to people and children in whom a gene mutation causing cone degeneration (retinal dystrophy) has occurred.

[0051] Other features, details, and advantages are shown in the following detailed description and drawings.

Brief Description of the Drawings

[0052]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Modes for Carrying Out the Invention

[0053] Active and Passive Filters As used herein, selectively blocking the wavelengths in the range where the cone cell protection filter exists means that even if blocking the transmission of at least a part of the wavelengths within the range, it has little or no effect on the transmission of visible wavelengths outside the range, especially unless it is configured to block this. The term "rejection rate" or "blocking rate" or "degree of blocking" or "filtering rate" refers to the percentage of incident light whose transmission is blocked within the range of one or more selected wavelengths. In contrast, the term "transmission rate" refers to the percentage of light that is actually transmitted. As an example, a transmission rate of 0% means that the filter does not transmit any light, so the corresponding blocking rate is 100%, which means that all the light directed towards the filter is blocked, absorbed, diffused or reflected. The parameter range of wavelength or bandwidth is defined as the full width at half maximum (FWHM).

[0054] The filter is defined by its "filtering spectrum" or "spectral characteristics" of the same meaning. The term "filtering spectrum" or "spectral characteristics" as used herein refers to the transmission rate of the filter in a plurality of wavelength ranges.

[0055] Now refer to Figure 3. Three filtering spectra are shown. One corresponds to the active matrix filter spectrum, another corresponds to the band-stop filter spectrum, and the remaining one corresponds to the long-pass filter spectrum. All of the filtering spectra are characterized by including a filtering peak in the range of 405 - 465 nm, preferably 425 - 445 nm.

[0056] A filter called a "long-pass filter" is configured to absorb more than 30%, preferably more than 50%, preferably more than 90%, preferably more than 99% of the incident light at wavelengths below the critical wavelength, and the critical wavelength is selected from the range of 405 - 465 nm, preferably 425 - 445 nm.

[0057] The long-pass filter is characterized by its ability to absorb light, which can also be expressed in terms of the optical density (OD). The optical density is the common logarithm of transmittance. For example, OD2 means that 99% of the light is absorbed by the filter.

[0058] A filter called a "band-stop filter" is configured to block more than 30%, preferably more than 50%, preferably more than 90%, preferably more than 99% of the incident light in a wavelength band ranging from 405 to 465 nm, preferably from 425 to 445 nm.

[0059] The filtering spectrum of an "active matrix filter" is characterized by the ability to preferably dynamically follow a harmful curve. It can block more than 30%, preferably more than 50%, preferably more than 90%, preferably more than 99% of the incident light at a specific wavelength.

[0060] The cut-off rate can be further customized by various parameters as follows. - Pupil size, for example, the product of multiplying the cut-off rate by the pupil size can be custom-adjusted, for example, so that the product is a constant. - Environment (brightness adjustment) and user activities (such as sports activities, labor, driving). - A predetermined maximum threshold.

[0061] Color balancing can be applied to the eye cone protection filter to, for example, reduce the yellow index Y1.

[0062] Referring now to FIG. 1. According to an embodiment of the present invention, the filter may be a passive filter. The passive filter may be a long-pass or band-stop filter. Preferably, the passive filter may be a light-shielding paint 50 with a transmittance of 10% or less, preferably 1% or less. The light-shielding paint 50 may be applied to the transparent surface 10 of the lens located in front of the eye 30.

[0063] The light-shielding paint 50 may be applied to the outer surface 12, or the inner surface 12, or an intermediate surface between these two end surfaces. Referring to FIG. 1, the light-shielding paint 50 is applied to the outer surface 11.

[0064] The light-shielding paint 50 may be applied to obtain light directed toward the eye below a predetermined maximum threshold.

[0065] Now referring to FIG. 2. According to another embodiment of the present invention, the active matrix 40, the cone cell protection filter may be an active filter, preferably applied to the outer surface 12, or the inner surface 12, or an intermediate surface between these two end surfaces. Referring to FIG. 2, the active matrix 40 is applied to an intermediate surface between the inner surface 12 and the outer surface 11.

[0066] The cone cell protection filter may further include a sensor 20. The sensor 20 may be a power meter, an LCD cell, a diode, an assembly of the above elements, or any sensor capable of converting an optical signal into an electrical signal. Preferably, the sensor 20 may be an assembly of diodes that converts an optical signal in the range of 405 - 465 nm, preferably 425 - 445 nm, in wavelength steps of 1 - 20 nm, preferably 10 nm. Thus, the sensor 20 can preferably measure the irradiance of the light to which the user is exposed in the form of an optical spectrum. Such measurements of physiological light are shown in Table 5 of Example 1.

[0067] The sensor 20 may be applied between the transparent surface 10 and the eye 30, preferably between the inner surface 11 and the eye 30. Also, the sensor may be applied to the user's glasses.

[0068] The cone cell protection filter may further include a memory MEM1. The memory MEM1 may be dedicated to storing information such as the danger of light to cone cells, a predetermined threshold, or user data. The memory MEM1 may be applied to the glasses.

[0069] Danger of light to cone cells (LHC) As used herein, the term "Light Hazard to Cones" (LHC), expressed as a percentage obtained by multiplying the surface area and dividing by the light dose, is the percentage of "harmfulness to cone cells" with respect to the "light dose", where the light is standard light, preferably reference sunlight, preferably D65 light defined for a continuous wavelength range over an exposure time of 15 hours.

[0070] LHC is calculated according to Equation 1, taking into account the measured hazard to cone cells and the corresponding light dose to the cone cells. [Equation 1] LHC = ∫ToC(λ) / D R (λ)dλ

[0071] Here, ToC is the harmfulness to cone cells, and D R is the light dose received by the irradiated cone cells.

[0072] As used herein, the "harmfulness to cone cells" is the difference between 100% and the percentage of surviving cone cells. The percentage of surviving cone cells is obtained, for example, by fluorescence with respect to cone cells, such as by calcein staining. For a plurality of wavelength ranges and a test time over several hours, preferably 15 hours, while a group of N i cone cells is irradiated with standard light, another group of N0 cone cells is not irradiated, for example, by being placed in the dark. Both groups of cone cells that show a positive reaction to calcein staining are considered to be surviving. Thus, the number V i of surviving cone cells irradiated with standard light and the number V0 of surviving cone cells that were not irradiated are obtained.

[0073] The number V i of surviving cone cells irradiated with standard light is further normalized by the number V0 of surviving cone cells in the dark control state. The harmfulness to cone cells expressed as a percentage is finally obtained by the following Equation 2.

Equation

[0074] Here, ToC is the degree of harm to cone cells expressed as a percentage (%), V i is the number of surviving cone cells irradiated with standard light, and V0 is the number of surviving cone cells that were not irradiated.

[0075] Refer to FIG. 6 here. This graph shows the degree of harm to eye cone cells, and the wavelength range of 400 - 470 nm shows the highest harm value.

[0076] The "light dose" or "energy" used in this specification corresponds to a value obtained by multiplying the power expressed in watts (W) or milliwatts (mW) by the time expressed in hours (h), minutes (min), or seconds (s). Preferably, the light dose is expressed as the product of milliwatts and time (mW·h) according to the formula of Equation (2). [Equation (2)] D R (λ)=I R (λ)*t

[0077] Here, I R is the irradiance of the standard light received by the irradiated cone cells, and t is the time expressed in seconds, minutes, or preferably hours.

[0078] Current cell death risk (CD) When using an active filter, the eye cone cell protection filter may further include a computer module MOD1 for calculating the above-mentioned formula and further formulas described below.

[0079] The computer module MOD1 may include a processor PROC1 and a memory MEM, and the input and output IN / OUT may be part of the computer module MOD1 attached to the glasses and communicable with the sensor 20 and the active matrix 40.

[0080] Processor PROC1 can receive input IN from sensor 20 and / or memory MEM1 via wired or wireless communication, Bluetooth, WiFi, NPC. In particular, processor PROC1 can receive the current optical spectrum from sensor 20, and the processor can receive user data and LHC values from memory MEM1.

[0081] Processor PROC1 may be able to calculate the "current cell death risk" or "cell death rate" (CD) caused by the light to which the above user is exposed. The cell death rate corresponds to the harmfulness of the light directed towards the eye cone cells, regardless of the presence or absence of filtering. Regarding the current cell death rate, user data, and a predetermined threshold value, processor PROC1 may be able to calculate the filtering characteristics of active matrix 40 via output command OUT. In fact, processor PROC1 can send output OUT to the active matrix via electrical wired or wireless communication.

[0082] As used herein, the term "current cell death risk" or "cell death rate" (CD) refers to a measure of the harmfulness to cone cells caused by the current transmitted light up to the eye, compared to LHC. The current cell death risk is further calculated according to Equation 4. [Equation 4] CD = ∬D(λ,t).LHC(λ)T lens (λ).dλ.dt

[0083] Here, CD is the cell death rate expressed as a percentage from 0 to 100%, D is the light dose received by the cone cells in real life considering the eyeball transmittance and the evaluation or measurement value of the user's light exposure in real life. The above spectral eyeball transmittance is expressed as a percentage from 0 to 100% and is defined by the Commission Internationale de l’eclairage (CIE, 2012) and is age-dependent. LHC is the risk of light to cone cell function. T lensis the current filtering spectrum of the filter. When no filter is provided on the transparent surface, T lens = 1.

[0084] The processor PROC1 can also calculate the cell harm reduction rate by comparing the cell death rate calculated considering the filtering characteristics with the cell death rate calculated considering any eye cone cell protection filter. The cell harm reduction rate is further calculated according to the following Equation 5.

Equation

[0085] where CD Lens is the cell death rate in the case of having a filter, TH is a predetermined maximum threshold value, CD0 is the cell death rate calculated for T Lens = 1.

[0086] Passive method The present invention also refers to a method that enables selecting a filter and adapting the filtering characteristics of the filter with respect to LHC and the calculated or estimated cell death risk.

[0087] Referring now to FIG. 4. The figure shows a method further associated with an embodiment using a passive matrix. A method for determining the configuration of one or more passive filters for protecting the eye will be described below based on user data associated with a specific environment.

[0088] In a first step S100, the processor PROC2 considers the user data, a predetermined maximum threshold value TH, and LHC. The user data, TH, and LHC are stored in a memory.

[0089] In a second step S200, according to the user data averaged over a week, more specifically the exposure at the user's location and the user's activities, the exposure time to light (t daylightCalculate it. The time can be expressed in days (d), hours (h), minutes (min), or seconds (s).

[0090] In the third step S300, estimate the cell death rate based on the exposure time to light. The formula enabling this calculation is described in Equation 6 below. [Equation 6] CD S3 =∬D S3 (λ,t).LHC(λ).dλ.dt

[0091] Here, CD S3 is the cell death rate calculated in S300, D S3 is the estimated dose of light received by cone cells taking into account the ocular transmittance. The above ocular transmittance is expressed as a percentage from 0 to 100%, is defined by the CIE, and is age-dependent. LHC is the risk of light to cone cell function.

[0092] More specifically, in step S300, the dose is calculated considering the light spectrum of sunlight, preferably D65 sunlight, and the time considered is the exposure time to light (tdaylight).

[0093] In the fourth step S400, compare the calculated cell death rate (CD) with a predetermined maximum threshold. If CD < TH, the cone cell protection filter is not provided. If TH < CD < a.TH, cone protection is necessary. The passive filter may be a long-pass or band-stop filter. If CD > a.TH, cone protection is extremely necessary. The passive filter may be a long-pass filter, preferably a light-shielding paint characterized in that the light-shielding paint has at least an optical density of 1, where "a" is a positive real number selected according to the user's data.

[0094] Parameter a may be set according to the user's activities, the user's physiological parameters, the user's age, and the average dose of light to which the user is exposed. For example, when the user works on a computer every day, the predetermined maximum threshold can be lowered by reducing parameter a. Conversely, when the user works more at night, the predetermined maximum threshold can be increased by slightly increasing parameter a.

[0095] In the final step S500, the filter characteristics are implemented to manufacture the optimized passive filter.

[0096] Active method Referring now to FIG. 5, the figure shows a method further associated with an embodiment using an active matrix. A method for determining the configuration of one or more active filters for protecting the eyes based on a specific user associated with a specific environment will be described below.

[0097] In the first step S1, the sensor 20 measures the light it receives. Accordingly, the sensor 20 preferably measures the irradiance of the light to which the user is exposed in the form of an optical spectrum by converting the optical signal into an electrical signal. The optical spectrum refers to the user's environment.

[0098] In the second step S2, the processor PROC1 calculates the optical spectrum and considers a specific wavelength range of 405 to 465 nm, preferably 425 to 445 nm.

[0099] In the first sub-step S31, the processor reads the user data (USD), LHC, and a predetermined maximum threshold from the memory MEM1.

[0100] In the second sub-step S32, the processor PROC1 calculates according to Equation 4, taking into account the LHC and considering the measured risk to the cone cells and the light dose to the corresponding cone cells. If the measured cell death rate (CD) is lower than TH, the user does not need an eye cone cell protection filter. If the measured cell death rate is higher than TH, step S3 is started.

[0101] In step S3, the processor PROC1 calculates the filtering characteristics of the active matrix. The filtering characteristics are based on the user's data and the cell death rate related to TH. For example, if the cell death rate is higher than TH over all wavelength ranges, the transmittance of the active matrix is the value obtained by dividing TH by the cell death rate CD. However, considering the user's data, there may be cases where it is suitable for the user to reduce a specific wavelength. Therefore, a coefficient (a) related to the user's data can be added over all wavelength ranges. Therefore, the transmittance is calculated according to Equation 7 below.

Equation

[0102] Here, T Lens,λ is the transmittance of the active matrix over a specific wavelength range, TH is a predetermined maximum threshold value, CD λ is the cell death rate over a specific wavelength range.

[0103] The parameter a may be set according to the user's activities, the user's physiological parameters, the user's age, and the average light dose to which the user is exposed. For example, if the user works on a computer every day, the predetermined maximum threshold value can be lowered by reducing the parameter a. Conversely, if the user works more at night, the predetermined maximum threshold value can be increased by slightly increasing the parameter a.

[0104] In the final step S4, T LensTaking this into account, the cell death rate (CD2) is calculated again according to Equation 4. If CD2 is still higher than TH, the transmittance of the filtering characteristics of the active matrix is increased, for example, the transmittance is reduced by 1, 2, 3, 4 or 5%.

[0105] Calculation method Reference is now made to FIG. 10 in which the method shown in FIG. 4 is implemented in computer module MOD2.

[0106] Computer module MOD2 includes at least memory MEM2, processor PROC2 and communication module COM. Computer module MOD2 may be connected to server SER. Server SER may be connected to computer module MOD2 and network NET. The network may be communicable with computers PHC1, PHC2, PHC3 of medical staff.

[0107] Medical staff, such as optometrists, ophthalmologists, nurses or doctors, can input user data and preferences into their own computers as described above. These data may be transmitted via network NET and stored in server SER.

[0108] Also, in an embodiment using personal goggles, by measuring the transparency of the cornea and lens for each individual patient and passing it to computer calculations, a person can obtain their own dedicated goggles adjusted according to their own transparency.

[0109] Starting from these data stored in server SER, processor PROC2 can calculate these data according to the above-described method shown in FIG. 4 to determine the filter characteristics regarding a predetermined maximum threshold.

[0110] Next, the filtering characteristics can be stored in the memory MEM2. The filtering characteristics can be communicated, for example, to a manufacturer via the communication module COM to provide a matched filter. The matched filter is, for example, a light-shielding paint having an optical density sufficient to transmit light with a harmfulness below a predetermined threshold value.

Example

[0111] Eye cone cell survival rate Refer to FIG. 8 here. This graph shows the eye cone cell survival rate for a plurality of irradiances at a plurality of wavelengths. In particular, the eye cone cell survival rate drops to almost 0% at wavelengths in the range of 400 - 430 nm and irradiances greater than 0.3 mW / cm 2 The irradiances and wavelengths considered in this graph are summarized in Table 1 below.

[0112]

Table 1

[0113] Refer to FIG. 9 here. This graph shows the effect of continued exposure of eye cone cells to light. The more exposure the eye cone cells have, the more the cell survival rate seems to be affected and drops to almost 0%. The light spectra considered are defined in Table 2 below.

[0114]

Table 2

[0115] Calculation of LHC and cone cell death rate Refer to Table 3 here. The harmfulness to cone cells disclosed below corresponds to the harmfulness caused to isolated primary cones irradiated in vitro with the sunlight spectrum (D65) at 10 nm intervals from 390 - 520 nm and at 630 nm as a comparison with red light (considered at 630 nm), taking into account that the anterior eye media naturally filters an irradiance of 0.3 mW / cm 2 for 15 hours at 430 nm.

[0116]

Table 3

[0117] For the primary cone, an appropriate irradiance of 0.39 mW / cm² used in vitro at 440 nm ± 5 nm 2 corresponds approximately to the irradiance of 0.93 mW / cm² received on the corneal surface of a 40-year-old person. 2

[0118] On a clear summer morning in Paris, when a calibrated spectroradiometer is directed from the 5th floor of a building towards the ground surface, the irradiance level may reach 0.46 mW / cm² at 440 nm ± 5 nm. 2 Already over this very narrow band (440 nm ± 5 nm), the irradiance used in vitro was only twice the irradiance measured in the real life of a very bright Parisian morning. Therefore, even in Paris, pedestrians may be at risk of encountering harmful levels of blue light on a clear summer day. Fortunately, a person cannot be exposed to light continuously for 15 hours, but since mitochondrial regeneration is not completed in a day, cumulative effects may be observed over a week. Finally, by further increasing the light levels in countries where people are more exposed to light by looking at the sky, when exposed to very reflective ground surfaces such as snow or clouds, the time required to induce lesions will be shortened. This photosensitization of cone photoreceptors can easily explain the visual impairments caused by looking directly at the sun for a few minutes during a solar eclipse or by indirect desert ground surface reflections. This can also accelerate the degenerative process in the field of retinal dystrophies that are more sensitive to oxidative stress.

[0119] Refer to Table 4 here. The LHC values are shown according to their wavelengths.

[0120]

Table 4

[0121] Preferably, the LHC is stored in memory. The LHC can further be made computable by a processor.

[0122] The purpose here is to estimate the harmfulness to the cones that occurs in real life due to exposure to sunlight. It is considered necessary to calculate the amount of light received by the eye, for example, over a one-week period.

[0123] Define two variables. - The time t of exposure to sunlight during a week daylight (h). This variable can vary in the range of 10 to 50 hours. - A predetermined maximum threshold (TH) expressed as a percentage. If it is below this predetermined maximum threshold, the light is considered to be not dangerous to the eye cone cells.

[0124] Exposure to sunlight has been evaluated under multiple light conditions, and the annual average is obtained considering at least the following. - Time and season, - Weather, - The orientation of the "eye", - Surroundings (for example, the 5th floor with a good view or the 1st floor of a street where a high-rise building is built).

[0125] Therefore, for the selected t daylight , it is possible to calculate the amount of light in real life received by the eye surface (DOSE_eye surface) from, for example, a cloudy day in winter to the afternoon of an extremely sunny day in summer with a good view.

[0126] When performing an optimal estimation of the amount of light received by the cones, the eye transmittance (T eye ) expressed as a percentage is taken into account. The above eye transmittance is defined by the CIE (for example, CIE 203:2012) and is age-dependent. Here, the calculation was performed for the eyes of 40-year-olds.

[0127] The current transmitted light spectrum corresponds to the spectrum of light at physiological light levels. This is sunlight exposure in real life and enables the calculation of the harmfulness to cone cells. For example, when the user is driving a car, the current light spectrum corresponds to the solar spectrum changed by the flash light and the transmittance of the windshield.

[0128] Table 5 is an example of the current transmitted light spectrum considering the eyeball transmittance of a 40-year-old user. The current transmitted light spectrum is measured by sensor 20 or inferred from the user's data.

[0129]

Table 5

[0130] The exposure time (t daylight ) to light is considered with respect to the user's data. In this example, t daylight = 50 h. Therefore, the dose can be calculated by multiplying the current transmitted light by t daylight as shown in Table 6.

[0131]

Table 6

[0132] Next, the cone cell death rate is calculated according to Equation 6. Table 7 below regrouped the values of the cone cell death rate again.

[0133]

Table 7

[0134] Selection of the filter From the current transmitted light to cone cells (see Table 5), the light risk to cone cells and LHC (Table 4), a certain t daylight and the cone cell death rate in real life when a certain harmfulness threshold TH lasts for one week (Table 7) can be calculated according to Equation 6.

[0135] The aim is to obtain a value of the cell death rate with a filter lower than a predetermined maximum threshold. Three different cases are described below.

[0136] The first case concerns the 5th floor of an office building on a very sunny day in Paris in summer. Therefore, the user is exposed to light for a long time.

[0137] t daylight is equal to 50 h (very high exposure to bright light / extreme situation).

[0138] The predetermined maximum threshold is selected by an algorithm, a healthcare professional such as an ophthalmologist or optometrist. In the case of this example, TH = 20%.

[0139] A cell death rate of 48% > TH is obtained.

[0140] Therefore, there is a high need to protect the cones in this situation of long-term exposure to bright light.

[0141] By using a long-pass filter that blocks all wavelengths less than 445 nm, the cell death rate can be reduced to near 20%, which is the defined harmful threshold, and the protection factor of the lens approaches 1.

[0142] The second case concerns the 1st floor of a narrow street in Paris on a very cloudy winter day. Therefore, the user is exposed to light for a long time.

[0143] t daylight is equal to 50 h (long-term exposure to light).

[0144] The predetermined maximum threshold is selected by an algorithm, a healthcare professional such as an ophthalmologist or optometrist. In the case of this example, TH = 20%.

[0145] A cell death rate close to 0% < TH is obtained.

[0146] Therefore, there is no need to protect the cone cells any further.

[0147] The third case relates to the fifth floor of an office building on a very sunny day in spring in Paris. Therefore, the user is exposed to moderate light.

[0148] t daylight is equal to 10 h (exposure to moderate light).

[0149] A predetermined maximum threshold is selected by an algorithm, a medical practitioner as an ophthalmologist or optometrist. In the case of this example, TH = 10%.

[0150] A cell death rate = 14% > TH is obtained.

[0151] Here, it is necessary to protect the cones. It is easy to protect the eye cone cells by a band-stop or long-pass filter and mitigate the cell death rate to less than TH.

[0152] Industrial applicability The present invention is applicable in the spectacle manufacturers, construction companies, automobile manufacturers, glass manufacturing companies, and the optical and optical communication industries.

[0153] The present invention is not limited to the cone protection filter and related methods which are merely examples described in this specification. The present invention includes all modifications that would be conceived by those skilled in the art when referring to this specification. Finally, some aspects of the present invention are described below. [Aspect 1] A cone cell protection filter for the eye, applied to at least one transparent surface, and by filtering the incident light on the transparent surface, intended to protect the user's eye cone cells from damage caused by irradiation at physiological light levels to the user's eyes, and having the following spectral characteristics, namely - filtering light wavelengths in the range of 405 to 465 nm, - a cone cell protection filter that transmits filtered light that travels towards the cone cells and has a harmfulness to the cone cells below a predetermined maximum threshold. [Aspect 2] The cone cell protection filter according to Aspect 1, wherein the spectral characteristics include a filtering peak in the range of 425 to 445 nm. [Aspect 3] Including an active matrix for filtering the incident light on the transparent surface, and the cone cell protection filter further - an input for receiving a measured value of the light transmitted between the transparent surface and the eye, - calculating the spectral characteristics of the cone cell protection filter based on at least * the measured value of the transmitted light, * the predetermined maximum threshold, and including a processor that controls the active matrix to filter the incident light based on the calculated spectral characteristics. The cone cell protection filter according to any one of Aspects 1 and 2. [Aspect 4] The cone cell protection filter according to Aspect 3, wherein the spectral characteristics include a filtering peak in the range of 425 to 445 nanometers, and the active matrix includes an electrochromic material. [Aspect 5] The cone cell protection filter according to any one of Aspects 1 and 2, wherein the filter is applied as a light-shielding paint to the transparent surface and is configured to absorb a certain portion of the incident light. [Aspect 6] The predetermined maximum threshold is - the type of activity of the user - the physiological parameters of the user - the age of the user, - the average amount of light to which the user is exposed The cone cell protection filter according to any one of Aspects 1 to 5, determined based on at least one of the elements. [Aspect 7] The cone cell protection filter according to any one of Aspects 1 to 6, configured to absorb a portion of the incident light higher than 99% at wavelengths below the critical wavelength. [Aspect 8] The cone cell protection filter according to aspect 7, wherein the critical wavelength is in the range of 425 nm to 445 nm. [Aspect 9] The predetermined maximum threshold is further determined to limit the power density to 0.2 mW / cm of the light directed to the cone cells. 2 The cone cell protection filter according to any one of aspects 1 to 8. [Aspect 10] A method for calculating the spectral characteristics of the cone cell protection filter according to aspect 3, comprising: a) Obtaining the light hazard to cone cells (LHC), defined by the cone cell death rate relative to the solar light incident light amount, for the solar light incident light and within at least one predetermined wavelength range; b) Measuring the irradiance of the current transmitted light between the transparent surface and the eye within the predetermined wavelength range, and estimating the current cell death risk based on the measured value of the transmitted light; c) When the current cell death risk exceeds a predetermined maximum threshold, calculating the spectral characteristics to attenuate the measured transmitted light, and repeating steps b) and c) until the current cell death risk is below the predetermined maximum threshold. [Aspect 11] A method for calculating the spectral characteristics of the cone cell protection filter according to aspect 5, comprising: a') Obtaining the light hazard to cone cells (LHC), defined by the cone cell death rate relative to the solar light incident light amount, for the solar light incident light and within at least one predetermined wavelength range; b') Estimating the light amount entering the eye based on the user's data over the predetermined wavelength range and within a predetermined time range; c') Estimating the current cell death risk within the given time range based on the estimated light amount; d') When the current cell death risk exceeds a predetermined maximum threshold, calculating the spectral characteristics to reduce the current transmitted light until the current cell death risk is below the predetermined maximum threshold. [Aspect 12] The method according to any one of aspects 10 to 11, wherein the current transmitted light is determined in a plurality of consecutive wavelength ranges, and the current cell death risk is given by the sum of the values obtained by multiplying the current transmitted light intensity in each of the wavelength ranges by the light hazard to cone cells (LHC). [Aspect 13] The spectral characteristics are given by the light transmittance Tlens(λ) defined by Tlens = TH / CD for each of the consecutive wavelength ranges (λ), where TH is the predetermined maximum threshold, The method according to the combination of aspect 10 and aspect 12, wherein CD is the current cell death risk level. [Aspect 14] A computer program for calculating the spectral characteristics of the eye cone cell protection filter according to aspect 3, the computer program including instruction codes for executing the method according to aspect 10 when executed by the processor. [Aspect 15] A computer program for calculating the spectral characteristics of the eye cone cell protection filter according to aspect 5, the computer program including instruction codes for executing the method according to aspect 11 when executed by the processor.

Explanation of Symbols

[0154] 10 Transparent surface 11 Outer surface 12 Inner surface 20 Sensor 30 User's age 40 Active matrix 50 Light-shielding paint

Claims

1. An eye cone cell protection filter for application to at least one transparent surface, configured to filter incident light on the transparent surface, for protecting the user's eye cone cells from damage caused by irradiation at physiological light levels to the user's eyes, and - filtering light wavelengths between 405 and 465 nanometers, - transmitting filtered light that reaches the eye cone cells and has a harmful degree of light to the eye cone cells below a predetermined threshold, having spectral characteristics such as the eye cone cell protection filter - an active matrix for filtering incident light on the transparent surface, - an input interface configured to receive a measured value of transmitted light between the transparent surface and the eye, - at least * the measured value of the transmitted light received by the input interface, * the predetermined threshold, A processor configured to calculate the spectral characteristics of the eye cone cell protection filter based on the above and to control the active matrix to filter incident light based on the calculated spectral characteristics. An eye cone cell protection filter comprising.

2. The spectral characteristics include peak absorption occurring at a predetermined filtering peak, The filtering peak is included between 425 and 445 nanometers. The eye cone cell protection filter according to claim 1.

3. The active matrix includes an electrochromic material. The eye cone cell protection filter according to claim 1 or 2.

4. An eye cone cell protection filter according to any one of claims 1 to 3, configured to absorb a proportion of incident light higher than 99% at wavelengths below a critical wavelength corresponding to a specific light wavelength.

5. The eye cone cell protection filter according to claim 4, wherein the critical wavelength is between 425 nanometers and 445 nanometers.

6. The predetermined threshold value further limits the power density of light reaching the cone cells of the eye to 0.2 mW / cm 2 The cone cell protection filter according to any one of claims 1 to 5.

7. A method for calculating the spectral characteristics of the eye cone cell protection filter according to claim 1, a) obtaining, for sunlight incident light and within at least one predetermined wavelength range, the light risk (LHC) for cone cells defined by the rate of eye cone cell death with respect to the sunlight incident light dose b) measuring the irradiance of the current transmitted light between the transparent surface and the eye within the predetermined wavelength range, and estimating the current cell death risk based on the measured value of the transmitted light and the light risk for cone cells; c) calculating the spectral characteristics to attenuate the measured transmitted light when the current cell death risk exceeds the predetermined threshold; repeating b) and c) until the current cell death risk is below the predetermined threshold. A method comprising the steps of.

8. wherein the current transmitted light is determined within a plurality of continuous wavelength ranges; The method according to claim 7, wherein the current cell death risk is given by the sum of the values obtained by multiplying the current transmitted light intensity in each of the wavelength ranges by the light risk (LHC) for cone cells.

9. for each of the continuous wavelength ranges (λ), the spectral characteristics are: given by a light transmittance Tlens(λ) defined by Tlens = TH / CD, where TH is the predetermined threshold, CD is the current cell death risk. The method according to claim 8, which quotes claim 7.

10. A computer program for calculating the spectral characteristics of the eye cone cell protection filter according to claim 1, wherein the computer program includes instruction codes for executing the method according to claim 7 when the instructions are executed by the processor. A computer program.

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