阅读说明：本技术 用于眼睛视锥细胞保护的滤光片 (Optical filter for eye cone cell protection ) 是由 M·玛丽 S·皮考德 V·弗拉多特 J·萨赫勒 T·维莱特 C·巴劳 C·埃里斯曼 于 2020-03-13 设计创作，主要内容包括：本发明涉及专用于保护眼睛视锥细胞的滤光片以及相关联的方法。眼睛视锥细胞保护滤光片旨在应用到透明表面,并且过滤入射光,用于防止用户的眼睛视锥细胞由于对所述用户的眼睛的生理光水平照射而受到损伤,并且具有以下光谱特征：i)过滤在405纳米与465纳米之间的光波长,以及ii)在预定义最大阈值下透射到达眼睛视锥细胞并对所述眼睛视锥细胞具有危害性的过滤光。(The present invention relates to filters intended for protecting the cone cells of the eye and to the associated method. An ocular cone protective filter is intended to be applied to a transparent surface and to filter incident light for preventing damage to a user's ocular cones from being irradiated by physiological light levels to the user's eye, and has the following spectral characteristics: i) filtering light wavelengths between 405 and 465 nanometers, and ii) filtering light transmitted to and harmful to eye cone cells at a predefined maximum threshold.)

1. An eye cone protective filter intended to be applied to at least one transparent surface to filter incident light on said transparent surface,

for preventing damage to the user's eye cones from physiological light level illumination of the user's eye,

and has the following spectral characteristics:

-filtering light wavelengths between 405 and 465 nanometers, and

-transmitting filtered light reaching and being harmful to the eye's cone cells below a predefined maximum threshold.

2. The eye cone protection filter of claim 1, wherein the spectral features comprise a filtering peak between 425 nanometers and 445 nanometers.

3. The ocular cone protection filter according to any one of claims 1 and 2, comprising an active matrix for filtering incident light on the transparent surface, the ocular cone protection filter further comprising:

-an input for receiving a measurement of light transmitted between the transparent surface and the eye,

-a processor for calculating spectral characteristics of the eye cone protective filter based on at least:

said transmitted light measurements, an

-the predefined maximum threshold value is set to a value,

and for controlling the active matrix to filter incident light based on the calculated spectral characteristics.

4. The eye cone protection filter of claim 3, wherein the spectral features comprise a filtering peak between 425 nanometers and 445 nanometers, and the active matrix comprises an electrochromic material.

5. The ocular cone protection filter of any one of claims 1 and 2, wherein the filter is applied to the transparent surface as a darkened hue and is configured to absorb a fixed proportion of incident light.

6. The eye cone protection filter according to any of the preceding claims, wherein the predefined maximum threshold is determined based on at least one element of:

-a type of activity of the user,

-a physiological parameter of the user,

-the age of the user,

-an average light dose to which the user is exposed.

7. The ocular cone protection filter of any preceding claim, configured to absorb a proportion of incident light above 99% at wavelengths below a critical wavelength.

8. The eye cone protection filter of claim 7, wherein the critical wavelength is between 425 nanometers and 445 nanometers.

9. The eye cone protection filter according to any one of the preceding claims, wherein the predefined maximum threshold is further determined to limit the power density of light reaching the eye cones to 0.2mW/cm²。

10. A method for calculating the spectral characteristics of the ocular cone protective filter of claim 3, the method comprising:

a) obtaining a Light Hazard (LHC) to cones, defined by a percentage of cone death of the eye related to the dose of the solar incident light, for the solar incident light and within at least one predetermined wavelength range,

b) measuring irradiance of currently transmitted light within the predetermined wavelength range between the transparent surface and the eye, and estimating a current cell death hazard percentage based on the transmitted light measurement,

c) calculating the spectral feature to reduce the measured transmitted light if the current cell death hazard percentage is above the predefined maximum threshold,

and repeating b) and c) until the current cell death hazard percentage is below the predefined maximum threshold.

11. A method for calculating the spectral characteristics of the ocular cone protective filter of claim 5, the method comprising:

a') obtaining a light damage to cones (LHC) for the incident solar light and within at least one predetermined wavelength range, said light damage to cones being defined by the percentage of cone death of the eye in relation to the dose of incident solar light,

b') estimating the light dose to the eye in the predetermined wavelength range and in a predefined time range from data of the user,

c') estimating a current cell death hazard percentage in the given time range based on the estimated light dose,

d') if said current cell death hazard percentage is above said predefined maximum threshold, calculating said spectral feature to reduce said current transmitted light until said current cell death hazard percentage is below said predefined maximum threshold.

12. The method according to any one of claims 10 and 11, wherein the current transmitted light is determined in a plurality of successive wavelength ranges, and the current cell death hazard percentage is derived by summing the products of the current transmitted irradiance of light in each of the wavelength ranges and the light hazard to cone cells (LHC).

13. Method according to claim 12 in combination with claim 10, wherein said spectral characteristics are derived by the light transmission, Tlens (λ), defined for each of said successive wavelength ranges (λ) by:

tlens ═ TH/CD, where:

TH is the predefined maximum threshold;

CD is the current cell death hazard percentage.

14. A computer program for calculating the spectral characteristics of the ocular cone protective filter according to claim 3, the computer program comprising: instruction code for performing the method according to claim 10 when the instructions are executed by the processor.

15. A computer program for calculating the spectral characteristics of the ocular cone protective filter according to claim 5, the computer program comprising: instruction code for performing the method according to claim 11, when the instructions are executed by a processor.

Technical Field

The present invention relates generally to the field of ocular cone protection filters intended to be applied to transparent surfaces such as eye-wear (e.g. sunglasses) to filter incident light. Embodiments of the invention relate to a method of determining a configuration for an eye's cone protection filter intended to be applied to at least one transparent surface.

Background

The electromagnetic spectrum covers a wide range of wavelengths, with wavelengths visible to the human eye often referred to as the visible spectrum covering the range of 380nm to 780 nm. Some wavelengths of the electromagnetic spectrum, including those in the visible spectrum, have deleterious effects, while others are known to have beneficial effects on the eye. Some wavelengths of the visible spectrum are also known to elicit a range of neuroendocrine, physiological and behavioral responses known as non-imaging (NIF) responses.

The vertebral retina is a light-sensitive tissue that lines the inner surface of the eye. This tissue has four major layers from the choroid to the vitreous humor: retinal pigment epithelium (hereinafter referred to as "RPE"); a photoreceptor layer (including rods and cones); an inner nuclear layer with bipolar cells, Muller cells, amacrine cells; and finally a ganglion cell layer comprising astrocytes, motile amacrine cells, and retinal ganglion cells with some intrinsic photosensitive ganglion cells (1% to 3% of retinal ganglion cells). This last cell type is important for circadian light traction (biorhythm) and pupil function.

Neural signals initiate rods and cones, and undergo complex processing by other neurons of the retina. The output from this process takes the form of action potentials in retinal ganglion cells, the axons of which form the optic nerve. Several important features of visual perception can be traced back to retinal coding and processing of light.

Photobiology, which studies the biological effects of light, has determined that a portion of the electromagnetic spectrum provides beneficial effects for good health, including visual perception and circadian function. However, it has also determined the importance of protecting both eyes from harmful radiation, such as Ultraviolet (UV) light. Even visible light of ordinary daily intensity may cause cumulative retinal damage or lead to retinal aging, and may be an aggravating factor in the development of early and late age-related maculopathy (ARM), such as age-related macular degeneration (AMD). There are indications in several epidemiological studies that the degree of exposure to sunlight may be correlated with the development of AMD.

Ophthalmic devices that filter out harmful UV radiation with low spectral selectivity are widely used. For example, ophthalmic clear lenses are designed to provide UV protection by protecting the eye from the harmful effects of UVA and UVB radiation. Intraocular lenses (IOLs) with UV filters were introduced in the 1990's; these are primarily cataract surgery implants to replace the lens.

Blue light filtering solutions already exist, including daily protection of clear lenses with a bluish violet filtering level of about 20%. However, these solutions are based on studies of phototoxicity of other types of retinal cells (RPE), and most studies are associated with higher toxic irradiance levels. For example, previous studies on RPE (Arnault et al, 2013, scientific public library. Synthesis [ PlosOne]Angle of refraction) indicates that light levels nearly 3 times higher are required to direct light compared to cones in vitroAnd has strong toxicity to RPE cells in vitro. For example, about 1.09mW/cm at 440nm is used²To cause 65% damage to primary RPE cells in vitro, while only requiring 0.39mW/cm at 440nm²To cause 85% damage to primary cone cells in vitro. Blue-violet filters have been designed specifically to reduce the transmission of the toxic blue band of the RPE (i.e. 415-. Existing blue-violet filters are mainly used as clear lenses for daily prevention of cumulative retinal damage, but they are not directed to specific cone protection where higher filtration rates are required.

Filters dedicated to protecting RPE can be found in US-8,360,574, EP 2602654 and EP 2602655. Indeed, it is known to those skilled in the art that blue light can damage the RPE. However, the effect of light on the cones is still poorly studied and is associated with visual pigments (especially green light). The light level required to damage the cones is not estimated.

Technical problem

This known solution is not optimized to protect the cone cells from phototoxicity, more particularly from blue light toxicity. Recent studies by the inventors have shown that blue light damages cone cells by producing higher cone cell mortality than RPE at lower light irradiance. Likewise, no green photodamage was confirmed, indicating that phototoxicity to the cones may be independent of visual pigment and indeed lie in the blue-violet range for the spectrum of sunlight reaching the retina. Photoreceptors are photodamaged, and this photodamage is usually due to activation of visual pigments.

Moreover, no method or solution provides filters specifically designed and adapted to filter light for cone protection. The filter is used to prevent phototoxicity, particularly in the cone cells.

Therefore, in view of the background, there is a need for an invention that can prevent blue light toxicity against cone cells.

Disclosure of Invention

The present invention improves this situation.

The present invention aims to provide an ocular cones protecting filter, which is intended to be applied to at least one transparent surface to filter the incident light on said transparent surface,

for preventing damage to the user's eye cones from physiological light level illumination of the user's eye,

and has the following spectral characteristics:

-filtering light wavelengths between 405 and 465 nanometers, and

-transmitting filtered light reaching and being harmful to the eye's cone cells below a predefined maximum threshold.

Thus, the ocular cone protective filter may have a spectral signature that includes a filtering peak between 425nm and 445 nm.

In fact, the phototoxicity on the cone cells of the eye reaches a maximum at wavelengths comprised between 425nm and 445nm (explained later).

Since the present invention is intended to protect the user's ocular cones from phototoxicity, it needs to be possible to apply the invention in any transparent surface.

The at least one transparent surface may be a transparent surface of glasses, sunglasses, eye protection glasses, virtual reality glasses, or even contact lenses, intraocular lenses, or ophthalmic medical devices. The at least one transparent surface may be a transparent surface of a window, windshield, screen, roof, or any transparent surface intended to prevent ambient light. Preferably, the at least one surface is a transparent surface of the lens. The light reaching the cones may be sunlight or any artificial light, such as the light of a light bulb, neon light, smartphone, computer or car headlight.

Physiological light level illumination refers to real life light to which the user's eye cones are exposed.

The filter may be an active filter or a passive filter suitable for application to any transparent surface as previously described.

As used herein, the term "filter" refers to and encompasses the term "eye cone protective filter" unless the properties of the filter are specified, and can be any passive or active filter.

The eye cone protection filter may partially cut off blue light in a wavelength range between 405nm and 465nm, preferably between 425nm and 445 nm.

According to an aspect of the present invention, there is provided an eye cone protective filter comprising an active matrix for filtering incident light on the transparent surface, the eye cone protective filter further comprising:

an input for receiving a measurement of light transmitted between the transparent surface and the eye,

-a processor for calculating spectral characteristics of the eye cone protective filter based on at least:

said transmitted light measurements, an

-the predefined maximum threshold value is set to a value,

and for controlling the active matrix to filter incident light based on the calculated spectral characteristics.

As such, the eye cone protective filter may have a spectral signature including a filtering peak between 425nm to 445nm, and the active matrix includes an electrochromic material.

As used herein, an "active filter" may be a filter that is capable of changing its filtered spectrum in real time by means of an active matrix. For example, the active matrix may include a chemical component that reacts with the light and thus changes its filter spectrum with respect to the amount of light received by the active filter. The active matrix may also be a chemical component associated with the power system that can exchange electrical energy with the chemical component in order to change the filtered spectrum of the active matrix and adjust the filtered spectrum accordingly in real time. Finally, the active matrix may be a filter, which comprises, in particular, electrical components that can adjust the filtered spectrum in real time.

For example, the active filter may be an LCD active matrix, a polarizing active matrix, more preferably an active matrix comprising electrochromic material.

According to another aspect of the invention, there is provided an ocular cone protection filter for use as a passive filter, for example an absorptive filter, a dye, a polar filter, a MOF, a photonic crystal, an interference filter deposited using a high refractive index, low refractive index material, a photochromic lens, a cholesteric layer, or a mixture of these solutions.

Preferably, the passive filter may be a darkened tone applied to a transparent surface and configured to absorb a fixed proportion of incident light.

As used herein, a "passive filter" may be a filter that is fully characterized by its filtered spectrum. Once the passive filter is manufactured, it is no longer possible to easily change its filter spectrum.

The eye cone protective filter may be configured to absorb a proportion of incident light above 99% at wavelengths below a critical wavelength.

Thus, the critical wavelength may be between 425nm and 445 nm.

The predefined maximum threshold may be determined based on at least one element of:

the type of activity of the user (e.g. work, running, swimming, cycling, horse riding, hunting, fishing, walking),

physiological parameters of the user (e.g. the individual's own filtering power, weight, height, form of the eyes, rim face curvature of the frame, frame shape, lens shape),

-the age of the user,

-an average light dose to which the user is exposed.

The predefined maximum threshold may be a percentage between 0% and 20%. In preferred embodiments, damage to the eye's cone should not be tolerated. Therefore, the predefined maximum threshold should be close to 0%. Thus, the predefined maximum threshold represents a detrimental effect that filtered light reaching the eye's cones causes on the eye's cones that should not be reached.

Recent studies by the inventors have shown that the average irradiance on the corneal surface is 12mW/cm over 400 to 500nm²Has been directed to in vitro visionCone damage is very large, especially for wavelengths between 425nm and 445nm, cone death approaches 90%.

In the graph of fig. 7, the two curves show that the eye cones are more sensitive than the RPE cells. In Arnault et al, 2013, "library of science, complex [ PlosOne ], RPE curves have been used to establish the toxicity of light to RPE cells. This curvilinear cone was recently used to establish the toxicity of light to cone cells. At 430nm, for example, it can be seen that light is almost three times as toxic to cone cells as to RPE cells.

In another embodiment, the predefined maximum threshold may be determined, as an example, from the average irradiance at the corneal surface over 405nm to 465nm, preferably 425nm to 445nm, obtained in the winter typical cloudy in paris where toxicity to the visual cone is not expected. Thus, the predefined maximum threshold may represent an irradiance threshold at which filtered light reaching the eye's cone cells does not arrive.

More generally, the predefined maximum threshold may be further determined to limit the irradiance of the light reaching the eye cells, preferably the eye cone cells, to 0.2mW/cm². In this case, it may be preferable that the eye cone protective filter includes an active matrix.

Furthermore, the present invention aims to provide, in an embodiment in which an active matrix may be used, for example, a method for calculating the spectral characteristics of an ocular cone protective filter, the method comprising:

a) obtaining a Light Hazard (LHC) to cones, defined by a percentage of cone death of the eye related to the dose of the solar incident light, for the solar incident light and within at least one predetermined wavelength range,

b) measuring irradiance of currently transmitted light within the predetermined wavelength range between the transparent surface and the eye, and estimating a current cell death hazard percentage based on the transmitted light measurement,

c) calculating the spectral feature to reduce the measured transmitted light if the current cell death hazard percentage is above the predefined maximum threshold,

and repeating b) and c) until the current cell death hazard percentage is below the predefined maximum threshold.

In an embodiment, for example, where passive filters may be used, it is intended to provide a method for calculating the spectral characteristics of an eye's cone protective filter, the method comprising:

a') obtaining a light damage to cones (LHC) for the incident solar light and within at least one predetermined wavelength range, the light damage to cones being defined by the percentage of cone death of the eye in relation to the dose of incident solar light,

b') estimating the light dose on the eye in said predetermined wavelength range and in a predefined time range based on data of the user,

c') estimating a current cell death hazard percentage in the given time range based on the estimated light dose,

d') if the current cell death hazard percentage is above the predefined maximum threshold, calculating the spectral feature to reduce the current transmitted light until the current cell death hazard percentage is below the predefined maximum threshold.

In any embodiment where active or passive filters may be used, the current transmitted light may be determined over a plurality of successive wavelength ranges, and the current cell death hazard percentage may be derived by summing the products of the current transmitted irradiance of light in each of the wavelength ranges and the light hazard to the cones.

In this way, the light hazard to cone cells can be derived by summing the percent of eye cone cell death associated with the solar incident light irradiance in each of the successive wavelength ranges. Solar incident light refers to all light that can reach the eye, such as diffuse light, reflected light, multiple diffused or multiple reflected light, that is added to light transmitted through a transparent surface from a transparent surface or other surrounding surface.

In an embodiment, for example but not exclusively using active matrices, the spectral characteristics can be derived by the light transmission Tlens (λ), defined for each of the successive wavelength ranges (λ) by:

tlens ═ TH/CD, where:

-TH is a predefined maximum threshold;

CD is the current percentage of cell death hazard,

more generally, said percent cone cell death of the eye related to solar incident light irradiance may be 0.39mW/cm in a) for a plurality of successive wavelength ranges, from the calcein staining test and at 440nm²Irradiance is obtained within fifteen hours.

The invention is also directed to a computer program for calculating spectral characteristics of an eye cone protective filter in an embodiment using an active matrix, the computer program comprising instruction code for performing a method according to an embodiment using an active lens when the instructions are executed by said processor.

This first computer program can be executed by a computer module MOD1 connected to the active filters 40 (for example electrochromic cells) of the active mirrors as shown in the example of embodiment of fig. 2. Module MOD1 may include:

an input interface IN for receiving ambient light data sensed by the sensor 20,

a processor PROC1 capable of cooperating with the memory unit MEM1 storing a first computer program (and at least the above-mentioned user data from which the threshold value can be calculated) to execute this first computer program and then process the data received from the sensor 20 to send a control signal to

An output interface OUT to control the active filter 40.

The invention is therefore also directed to an apparatus comprising the computer module MOD1 to implement the method according to the embodiment using active matrices.

The invention is also directed to another computer program for calculating spectral characteristics of an eye cone protective filter in an embodiment using a passive filter, the computer program comprising instruction code for performing a method according to an embodiment using a passive lens when the instructions are executed by said processor.

This second computer program can be executed by the computer module MOD2 (shown in fig. 10) of the server SER which is connected via the network NET to a computer device for professional healthcare PCH1, PCH2 or the like which transmits the data of the user of the future wearer to the server SER. The MOD2 module of the server SER may include:

a communication interface COM for receiving user data,

a processor PROC2 able to cooperate with the memory unit MEM2 storing a second computer program to execute this second computer program and then to process the user data received from the interface COM to calculate the spectral characteristics of the passive filter for the passive lens worn by this user according to an embodiment using passive lenses.

The invention is also directed to a server comprising a computer module MOD2 to implement the method according to the embodiment using passive optics.

Problem solving scheme

The present invention thus makes it possible to provide an eye cone protection filter which is dedicated to eye cone protection. In fact, the invention discloses a method of providing a filter with a filtered spectrum that takes into account the ambient light and the activities and pathologies of the user, in order to protect the user's cone cells from blue light toxicity, even in low light conditions. Moreover, the present invention takes into account the fact that cone cells are more sensitive than RPE, and therefore require special protection in specific wavelengths and at specific light threshold intensities, and have higher levels of filtering than the prior art filters provided.

Likewise, the disclosure of this document relates to isolated cones in which no aging model is present in any case. Thus, the disclosure of this document may focus on any user of any age. In particular, the disclosure of this document may be directed to people and children who have genetic mutations that lead to cone degeneration (retinal dystrophy).

Drawings

Other features, details and advantages will be apparent from the following detailed description and the accompanying drawings, in which:

FIG. 1 shows a schematic view of a

FIG. 1 is a diagram of an active matrix applied on a transparent surface according to an embodiment of the invention;

FIG. 2

FIG. 2 is a diagram of a passive filter applied on a transparent surface;

FIG. 3

FIG. 3 is a graph of three different filtered spectra of three different eye cone protective filters according to an embodiment of the invention;

FIG. 4

FIG. 4 is a diagram illustrating a method for calculating spectral characteristics of an eye cone protective filter using an active matrix according to an embodiment of the present invention;

FIG. 5

FIG. 5 is a schematic diagram illustrating a method for calculating spectral characteristics of an eye cone protective filter using passive filters according to an embodiment of the invention;

FIG. 6

FIG. 6 is a spectrum of toxic effects of light on primary ocular cone cells established in vitro after normalizing the irradiance levels of each 10-nm band to the solar spectrum arriving at the retina;

FIG. 7

FIG. 7 is a graph for establishing in vitro irradiance for light-induced toxicity to the RPE and cones;

FIG. 8

FIG. 8 is a graph of cone cell survival for different wavelengths under several irradiances;

FIG. 9

FIG. 9 is a graph of cone cell survival for different wavelengths for different light exposure durations at several irradiances;

FIG. 10 shows a schematic view of a

FIG. 10 is a network organization diagram capable of providing a user with an eye cone filter according to an embodiment of the invention.

Detailed Description

Active optical filter and passive optical filter

As used herein, an ocular cone protection filter selectively suppresses a range of wavelengths if it suppresses at least some transmission of the range of wavelengths while having little or no effect on transmission of visible wavelengths outside the range (unless it is expressly configured for use herein). The term "rejection" or "inhibition" or "degree of inhibition" or "filtration" refers to the percentage of incident light in one or more selected wavelength ranges that is prevented from being transmitted. Conversely, the term "transmittance" refers to the percentage of light that is actually transmitted. For example, a transmission of 0% means that no light is transmitted through the filter, so the corresponding rejection is 100%, and all light reaching the filter is blocked, absorbed, diffused, or reflected. The parameter "wavelength or bandwidth range" is defined as the full width at half maximum (FWHM).

A filter is defined by its "filtered spectrum" or, within the same meaning, "spectral signature". As used herein, the term "filtered spectrum" or "spectral feature" refers to the transmittance of a filter according to a plurality of wavelength ranges.

Reference is now made to fig. 3. Three filtered spectra are shown. One corresponding to the active matrix filtered spectrum, another corresponding to the band stop filtered spectrum and another corresponding to the long pass filtered spectrum. All filtered spectra are characterized in that they comprise a filtered peak between 405nm and 465nm, preferably between 425nm and 445 nm.

The filter, known as "long-pass filter", is configured to absorb a proportion of incident light higher than 30%, preferably higher than 50%, preferably higher than 90%, preferably higher than 99%, at wavelengths lower than a critical wavelength selected from 405nm to 465nm, preferably from 425nm to 445 nm.

The long-pass filter is characterized by its ability to absorb light; this capability can also be expressed in terms of Optical Density (OD). The optical density is the decimal logarithm of the transmission. For example, OD2 means that 99% of the light is absorbed by the filter.

The filter, known as "band-stop filter", is configured to cut off a proportion of incident light higher than 30%, preferably higher than 50%, preferably higher than 90%, preferably higher than 99%, at a wavelength band comprised between 405nm and 465nm, preferably 425nm to 445 nm.

The filtered spectrum of an "active matrix filter" is characterized by its ability to follow the toxicity curve, preferably in a dynamic manner. It may cut off a proportion of incident light above 30%, preferably above 50%, preferably above 90%, preferably above 99% at a specific wavelength,

the cutoff ratio can be further customized according to various parameters:

the pupil size, e.g. the product of the cut-off ratio times the pupil size, can be custom adjusted, e.g. the product can be constant,

environment (more or less luminous) and user's activities (e.g. sports activity, work, driving),

-a predefined maximum threshold.

Color balance may also be provided to the eye cone protection filter to reduce, for example, the yellowness index Y1.

Reference is now made to fig. 1. According to an embodiment of the 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 darkened shade 50 of transmission equal to or less than 10%, preferably equal to or less than 1%. The darkened tint 50 may be applied to the transparent surface 10 of the lens that is in front of the eye 30.

The darkened shade 50 may be applied to the outer surface 12, or the inner surface 12, or between the two extreme surfaces. Referring to fig. 1, a darkened shade 50 is applied to the outer surface 11.

A darkening hue 50 may be provided in order to obtain light reaching the eye that is below a predefined maximum threshold.

Reference is now made to fig. 2. According to another embodiment of the invention, the eye cone protective filter may be an active filter, preferably applied to the outer surface 12, or the inner surface 12, or the active matrix 40 between these two extreme surfaces. Referring to fig. 2, an active matrix 40 is applied between the inner surface 12 and the outer surface 11.

The eye cone protective filter may further comprise a sensor 20. The sensor 20 may be a power meter, an LCD unit, a diode, a component of said elements or any sensor capable of converting an optical signal into an electrical signal. Preferably, the sensor 20 may be a diode assembly converting the optical signal from 405nm to 465nm, preferably from 425 to 445nm, in 1 to 20nm wavelength steps, preferably in 10nm wavelength steps. Thus, the sensor 20 may measure the irradiance of the light to which the user is exposed, preferably in the form of a spectrum of light. Such physiological light measurements are shown in table 5 of example 1.

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 eyewear.

The eye cone protective filter may further comprise a memory MEM 1. The memory MEM1 may be dedicated to storing information such as light hazards to the cone cells, predefined thresholds or data of the user. Memory MEM1 may be applied to an eyewear.

Light hazard to cone cells (LHC)

As used herein, the term "light hazard to cones" (LHC) (expressed as a percentage multiplied by the surface and divided by the light dose) is the percentage of "toxicity to cone cells" with respect to the "light dose", where light is a reference light, preferably a reference sunlight, and preferably a D65 light, defined for a 15 hour exposure time for successive wavelength ranges.

LHC is calculated according to equation math.1 taking into account the measured toxicity to the cone cells and the corresponding dose to the cone cells.

[Math.1]

LHC＝∫ToC(λ)/D_R(λ)dλ

Wherein ToC is toxicity to cone cells, and D_RIs formed by irradiated cone cellsThe amount of light received.

As used herein, "toxicity to cone cells" is the difference between 100% and the percentage of viable cone cells. The percentage of surviving cones can be obtained, for example, by fluorescence of the cones, for example, by calcein staining. Set of N for a plurality of wavelength ranges and for a test duration of several hours, preferably 15 hours_iThe cone cells are irradiated with reference light while another group N₀The cones are not irradiated, for example by being placed in the dark. Both sets of cone cells that reacted positively to calcein were considered viable. Thus, the number V of viable cone cells irradiated by the reference light is obtained_iAnd the number V of non-irradiated viable cones₀。

Number of viable cone cells irradiated with reference light V_iIs determined by the number V of viable cones under dark control₀To further normalize. Toxicity to cone cells, expressed as a percentage, was finally obtained according to equation Math.2.

[Math.2]

Wherein ToC is the toxicity to cone cells in percent (%); v_iIs the number of viable cones irradiated by reference light, and V₀Is the number of non-irradiated viable cones.

Reference is now made to fig. 6. This figure shows toxicity to cone cells of the eye, including wavelengths between 400nm and 470nm showing the highest toxicity values.

As used herein, "light dose" or "energy" corresponds to the time in power in watts (W) or milliwatts (mW) multiplied by hours (h), minutes (min), or seconds(s), preferably the light dose is expressed in milliwatts multiplied by hours (mw.h), as shown by the equation math.2.

[Math.2]

D_R(λ)＝I_R(λ)*t

Wherein, I_RIs the irradiance of the reference light received by the irradiated cone cells; and t is the time in seconds, minutes or preferably hours.

Current hazards of Cell Death (CD)

When an active filter is used, the eye cone protective filter may further comprise a computer module MOD1 in order to calculate the above equation and further equations which will now be described.

The computer module MOD1 may comprise a processor PROC1, a memory MEM, and the inputs and outputs IN/OUT may be part of a computer module MOD1 fitted to the eye-wear and able to communicate with the sensors 20 and the active matrix 40.

The processor PROC1 may receive input IN from the sensors 20 and/or from the memory MEM1 via wire or wireless communication, bluetooth, WiFi, NPC. In particular, the processor PROC1 may receive the current spectrum from the sensor 20 and the processor may receive the user's data and LHC values from the memory MEM 1.

The processor PROC1 may be capable of calculating the "current cell death hazard" or "cell death" (CD) caused by the light to which the user is exposed. Cell death corresponds to the harmfulness of the light (whether filtered or not) reaching the cones of the eye. With respect to this current cell death and user data and predefined thresholds, the processor PROC1 may calculate the filtering characteristics of the active matrix 40 via the output instruction OUT. In practice, processor PROC1 may send output OUT to the active matrix via wire or wireless communication.

As used herein, the term "present cell death hazard" or "cell death" (CD) refers to a measure of the toxicity to cone cells resulting from present light transmitted to the eye compared to LHC. The current cell death hazard is further calculated according to equation Math.4.

[Math.4]

CD＝∫∫D(λ,t).LHC(λ)T_lens(λ).dλ.dt

Wherein CD is cell death expressed as a percentage of 0% to 100%;

d is the light dose received by the real-life cone cells, taking into account the eye transmittance and an estimate or measurement of the user's real-life light exposure. The spectral eye transmittance is expressed as a percentage between 0% and 100% and is defined by the international commission on illumination (CIE,2012) and depends on age;

LHC is a light hazard to cone cell function;

T_lensis the current filtered spectrum of the filter. If no filter is provided on the transparent surface, T_lens＝1。

The processor PROC1 may also calculate the reduction in cytotoxicity compared to the cell death calculated taking into account the filtering characteristics or taking into account any eye cone protection filters. The cytotoxicity reduction rate was further calculated according to the following equation Math.5.

[Math.5]

Wherein, CD_LensIs cell death obtained with a filter;

TH is a predefined maximum threshold;

and CD₀Is directed to T_LensCell death calculated as 1.

Passive method

The invention also relates to a method capable of selecting an optical filter and adjusting the filtering characteristics of said optical filter with respect to the LHC and the calculated or estimated percentage of cell death hazard.

Reference is now made to fig. 4. This figure illustrates a method further associated with embodiments using passive matrices. A method for determining the configuration of one or more eye-protection passive filters based on data of a user associated with a particular environment will now be described.

In a first step S100, the processor PROC2 takes into account the user' S data, a predefined maximum threshold TH and LHC. The user's data, TH and LHC are stored in memory.

In a second step S200, the duration of exposure to light (t) is calculated from the average data of the user over a week, more specifically from the user' S position and the exposure of his activity_daylight). This duration may be expressed in days (d), hours (h), minutes (min) or seconds(s).

In a third step S300, cell death is estimated from the duration of exposure to light. The equation to achieve this calculation is described in the following equation Math.6:

[Math.6]

CD_S3＝∫∫D_S3(λ，t).LHC(λ).dλ.dt

wherein, CD_S3Is cell death calculated in S300;

D_S3is the estimated dose of light received by the cone cells, taking into account the eye transmittance. The eye transmittance is expressed as a percentage between 0% and 100% and is defined by CIE and depends on age;

LHC is a light hazard to cone cell function;

more specifically, in step S300, the dose is calculated considering the spectrum of the reference sunlight, preferably D65 reference sunlight, and the considered time is the duration of exposure to light (tdaylight).

In a fourth step S400, the calculated Cell Death (CD) is compared to a predefined maximum threshold.

If CD < TH, no eye cone protective filter is provided.

Cone protection is required if TH < CD < a. The passive filter may be a long pass or band stop filter.

Cone protection is strongly required if CD > a.th. The passive filter may be a long-pass filter, preferably a darkened shade, characterized in that the darkened shade has an optical density of at least 1, where "a" is a positive real number selected according to the user's data;

the parameter a may operate in dependence of the activity of the user, physiological parameters of the user, age of the user, average light dose to which said user is exposed. For example, if the user is working on the computer every day, the parameter a may be decreased to decrease the predefined maximum threshold. Conversely, if the user is working more often at night, the parameter a may be increased slightly to slightly increase the predefined maximum threshold.

In a final step S500, filter characteristics are implemented for manufacturing an optimized passive filter.

Active method

Reference is now made to fig. 5. The figure illustrates a method further associated with embodiments using an active matrix. A method for determining the configuration of one or more eye-protection active filters based on a particular user associated with a particular environment will now be described.

In an initial step S1, the sensor 20 measures the light it receives. Thus, the sensor 20 measures the irradiance of the light, preferably in the form of a spectrum, to which the user is exposed by converting the light signal into an electrical signal. The spectrum refers to the environment of the user.

In a second step S2, the processor PROC1 calculates this spectrum and takes into account specific wavelengths in the range 405nm to 465nm, preferably 425nm to 445 nm.

In a first sub-step S31, the processor reads the user' S data (USD), LHC and a predefined maximum threshold from the memory MEM 1;

in a second substep S32, the processor PROC1 calculates the cell death caused by the measured spectrum according to equation math.4, taking LHC into account. If the measured Cell Death (CD) is below TH, the user does not need an eye cone protection filter. If the measured cell death is higher than TH, step S3 is initiated.

In step S3, the processor PROC1 calculates the filter characteristic of the active matrix. The filtering characteristics are based on the user's data and cell death with respect to TH. For example, for each wavelength range, if cell death is higher than TH, the transmittance of the active matrix is TH divided by cell death CD. However, considering the user's data, it is preferable for the user to lower some specific wavelengths. Therefore, for each wavelength range, the coefficient (a) of the data on the user can be added. Therefore, the transmittance is calculated according to the following equation math.7:

[Math.7]

wherein, T_Lens,λIs the transmittance of the active matrix for a particular range of wavelengths;

TH is a predefined maximum threshold;

CD_λis directed to cell death in a particular wavelength range.

The parameter a may operate in dependence of the activity of the user, physiological parameters of the user, age of the user, average light dose to which said user is exposed. For example, if the user is working on the computer every day, the parameter a may be decreased to decrease the predefined maximum threshold. Conversely, if the user is working more often at night, the parameter a may be increased slightly to slightly increase the predefined maximum threshold.

In a final step S4, T is considered according to equation Math.4_LensCell death (CD2) was recalculated. If the CD2 is still higher than TH, the transmittance of the filtering feature of the active matrix is increased, e.g., the transmittance is reduced by 1%, 2%, 3%, 4%, or 5%.

Calculation method

Reference is now made to fig. 10, in which the method shown in fig. 4 is implemented in a computer module MOD 2.

The computer module MOD2 comprises at least a memory MEM2, a processor PROC2 and a communication module COM. The computer module MOD2 may be connected to the server SER. The server SER may be connected to a computer module MOD2 and to a network NET. The network may be capable of communicating with the healthcare professional computers PHC1, PHC2, PHC 3.

Healthcare professionals (e.g., an optician, ophthalmologist, nurse or doctor) can enter the user's data and preferences as described above into their computers. These data can be transmitted via the network NET and stored in the server SER.

Also, in embodiments using personalized goggles, the transparency of the cornea and lens may be measured for individual patients and introduced into the computer so that one person has a particular goggle adjusted for its transparency.

Starting from these data stored in the server SER, the processor PROC2 may calculate these data according to the method described above and illustrated in fig. 4, in order to determine the filter characteristics with respect to a predefined maximum threshold value.

The filtering characteristics may then be stored in the memory MEM 2. The filter features may communicate with, for example, a manufacturer via the communication module COM in order to provide an adapted filter. The adaptive filter is, for example, a darkened shade of light of sufficient optical density to transmit harmful light below a predefined threshold.

Examples of the invention

Cone cell survival rate of eye

Reference is now made to fig. 8. This figure shows the ocular cone cell viability at several wavelengths of irradiance. In particular, the irradiance is greater than 0.3mW/cm at wavelengths comprised between 400nm and 430nm²In the case of (2), the ocular cone cell survival rate drops to almost 0%. The irradiance and wavelength considered for this figure are summarized in table 1 below.

[ Table 1]

Reference is now made to fig. 9. This figure shows the effect of light exposure duration on the cones of the eye. It appears that the more cones of the eye that are exposed, the greater the influence on the cell viability and almost drops to 0%. The spectra considered are defined in table 2 below.

[ Table 2]

Calculation of LHC and Cone cell death

Reference is now made to table 3.Toxicity to cone cells disclosed below corresponds to a range of 0.3mW/cm at 430nm after natural filtration of the anterior ocular media over 15h, taken into account²Irradiance of (c), toxicity obtained on isolated primary cones illuminated in 10nm steps from 390nm to 520nm and in vitro for the 630nm solar spectrum (D65), as a comparison between red light (considered at 630 nm).

[ Table 3]

0.39mW/cm used at 440nm +/-5nm for in vitro primary cones²A moderate irradiance corresponds approximately to 0.93mW/cm received on the corneal surface of a 40 year old person²Irradiance is measured.

In the morning of Paris, in summer, when the calibrated spectral radiometer is directed down from the building's five floors to the ground, the irradiance level at 440nm +/-5nm may reach 0.46mW/cm². Already at this very narrow band (440nm +/-5nm), the irradiance used in vitro was only 2 times the irradiance measured in real life in the morning of a very bright paris. Thus, even in paris, pedestrians may encounter toxic blue light levels in the sunny summer days. Fortunately, he may not be exposed for 15 hours continuously, but a cumulative effect over one week may be observed, since mitochondrial turnover is not completed within one day. Finally, in more exposed countries, by observing the sky, further increasing the light level when exposed to very reflective ground such as snow or clouds will reduce the time required to cause the lesions. This photosensitization of cone photoreceptors can easily account for the visual impact caused by direct observation in the solar direction for a few minutes during solar eclipse or by indirect desert ground reflections. It also accelerates the degenerative process in the case of retinal dystrophies which show a higher sensitivity to oxidative stress.

Reference is now made to table 4. The values of LHC are presented depending on their wavelength.

[ Table 4]

Preferably, the LHC is memorized into memory. The LHC may be further calculated by a processor.

The goal is now to estimate real-life toxicity to cone cells caused by solar exposure. For example, it is contemplated that the light dose received by the eye within 1 week needs to be calculated.

Two variables are defined:

time under sunlight exposure, t, within 1 week_daylight(h) In that respect This variable may vary between 10 and 50 hours.

-a predefined maximum Threshold (TH) in percentage. Below this predefined maximum threshold, light may be considered non-toxic to the cones of the eye.

Solar exposure has been evaluated under a variety of lighting conditions, averaging one year, at least taking into account

-the time of day and the time of year,

-the weather, the weather being,

-the orientation of the "eyes",

-the surroundings (e.g. five buildings with a clear view or one building on a street with a tall building).

Thus, for example, from cloudy days in winter to very fine afternoon with a clear view in summer, the eye surface of the eye (DOSE _ EYE surface) at the selected t can be calculated_daylightThe received real life light dose.

Eye transmittance (T)_eyeExpressed as a percentage) is taken into account for the best estimation of the light dose received by the cone. The eye transmittance is defined by CIE (e.g., CIE 203:2012) and depends on age. Here, the calculation is performed for the 40 year old eye.

The current transmission spectrum corresponds to a spectrum at physiological light levels. It is a real-life sun exposure that will enable the calculation of toxicity to cone cells. For example, if the user is driving a car, the current spectrum will correspond to the solar spectrum, varying with the transmittance of the flash and windshield.

Table 5 is an example of a current transmission spectrum, taking into account the eye transmission of a 40 year old user. The current transmission spectrum is measured by the sensor 20 or derived from the user's data.

[ Table 5]

Duration of exposure to light (t)_daylight) Is considered to be data about the user. In this example, t_daylight50 h. Therefore, the current transmission light can be compared with t_daylightThe doses were calculated by multiplication as shown in table 6.

[ Table 6]

Cone cell death was then calculated according to equation math.6. Table 7 below reassembles the values for cone cell death.

[ Table 7]

Selection of filters

From the current transmitted light to the cone cells (see Table 5), the light hazard LHC to the cones (Table 4), for fixed t_daylightAnd fixed toxicity threshold TH real-life cone cell death within 1 week (table 7) can be calculated from math.6.

The aim is to obtain cell death values with filters that are less than a predefined maximum threshold. Three different scenarios are described below.

The first scenario involves a very bright sunny day, in the summer of paris, on floor 5 of an office building. Thus, the user is exposed to prolonged light exposure.

t_daylightEqual to 50h (very high exposure to intense light/extreme case).

The predefined maximum threshold is selected by an algorithm, a health care professional (e.g. ophthalmologist or optician). In this case of this example, TH is 20%.

Obtaining: cell death 48% TH.

Therefore, in the case of such a long-time strong light exposure, the protection of the viewing cone is strongly required.

Using a long pass filter cutting all wavelengths below 445nm, cell death can be reduced to nearly 20%, which is a defined toxicity threshold, which brings the protection factor of the lens close to 1.

The second case relates to a very cloudy winter, in paris, on level 1 of a street. Thus, the user is exposed to prolonged light exposure.

t_daylightEqual to 50h (long light exposure).

The predefined maximum threshold is selected by an algorithm, a health care professional (e.g. ophthalmologist or optician). In this case of this example, TH is 20%.

Obtaining: cell death was close to 0% < TH.

Therefore, no additional cone protection is required.

The third case relates to a very bright sunny day, in spring, in paris, in floor 5 of an office building. Thus, the user is exposed to moderate light exposure.

t_daylightEqual to 10h (moderate light exposure)

The predefined maximum threshold is selected by an algorithm, a health care professional (e.g. ophthalmologist or optician). In this case of this example, TH is 10%

Obtaining: cell death ═ 14% > TH.

Here, cone protection is required. Due to the band-stop or long-pass filters, it is easy to protect the eye's cone cells at TH and to reduce cell death.

INDUSTRIAL APPLICABILITY

The invention can be used in the ophthalmic, construction, automotive, glass manufacturing and optical and photonic industries.

The present invention is not limited to the eye-cone protective filters and associated methods described herein, which are intended to be exemplary only. The invention includes every alternative that would occur to one of skill in the art upon reading this disclosure.

List of reference numerals

-10: transparent surface

-11: outer surface

-12: inner surface

-20: sensor with a sensor element

-30: age of the user

-40: active matrix

-50: darkened color tone