A display screen anti-blue light optical film

Abstract

This invention relates to a blue light blocking optical film for display screens. Several sampling points are selected on the display screen. Based on measured data from each sampling point, the spectral radiant power corresponding to each sampling point is obtained. Based on the spectral radiant power of each sampling point, the blue light radiation energy corresponding to each sampling point is calculated according to the spectral radiant power and a blue light hazard weighting coefficient. The blue light radiation energy corresponding to each sampling point is compared with a corresponding safety threshold. Based on the comparison result, a blue light radiation filtering coefficient is assigned to the sampling point. Surface fitting is performed based on the data of each sampling point to generate a blue light radiation filtering coefficient distribution function that the blue light blocking optical film should have. Based on this, the blue light blocking optical film is prepared. This blue light blocking optical film is more in line with actual conditions and can be used to adhere to the outermost LCD screen, OLED screen, MiniLED screen, or Micro LED screen.

Description

TECHNICAL FIELD

[0001] The present application relates to a display screen anti-blue light optical film, which is mainly applicable to various medical and civilian display screens and smart phone screens. BACKGROUND

[0002] Blue light refers to visible light with a wavelength in the range of 380nm-700nm on the spectrum. This type of visible light has a short wavelength and high energy, and is the main cause of retinal damage in the human eye after exposure. The possibility of photochemical retinal damage caused by exposure amount between wavelengths of 380nm-700nm is usually referred to as blue light hazard (BLH).

[0003] To reduce or eliminate the blue light hazard, an optical film capable of blocking / filtering blue light can be attached or prepared on the display screen. For example, Chinese patent document CN114806438A discloses a blue light-proof screen sticker film and a preparation method thereof. The blue light-proof screen sticker film comprises the following raw materials: a silica gel layer, a first OCA glue, a second OCA glue, and a high-color-point perovskite quantum dot film. The first OCA glue, the high-color-point perovskite quantum dot film, and the second OCA glue are sequentially arranged on the back of the silica gel layer from top to bottom. The preparation method comprises the following specific steps: after the first OCA glue is coated on the back of the silica gel layer, the high-color-point perovskite quantum dot film is transferred, and then the second OCA glue is used for packaging to obtain the blue light-proof screen sticker film. The blue light-proof screen sticker film is green and is an external sticker film of an electronic display screen. The green quantum dots absorb more blue light and convert it into green light. Then, a red light absorber is matched to reduce the change of CCT, thereby forming a blue light-proof screen sticker film that meets the high-level RPF standard. Chinese patent document CN216956422U discloses a blue light-proof eye protection film for a super large display screen. The blue light-proof eye protection film comprises a protective layer, a first adhesive layer, a blue light-proof layer, a heat dissipation layer, a second adhesive layer, and a protective layer. The protective layer is arranged above the first adhesive layer, the first adhesive layer is arranged above the blue light-proof layer, the blue light-proof layer is arranged above the heat dissipation layer, the heat dissipation layer is arranged above the second adhesive layer, and the second adhesive layer is arranged above the protective layer. The blue light-proof layer is composed of a nano grating layer and a reinforcing layer. The nano grating layer is arranged above the reinforcing layer and has a nano grating microstructure. The blue light-proof layer is attached together through the first adhesive layer and the protective layer, and the heat dissipation layer is attached together through the second adhesive layer and the protective layer. The blue light-proof eye protection film can accurately filter the short-wave blue light of 430 nm to 460 nm of electronic products, inhibit environmental glare, has no color deviation, is low in cost, and is simple and convenient to attach. The blue light-proof eye protection film has no air bubble residue. The blue light-proof eye protection film is applied to a super large display screen and can greatly reduce the harm of harmful blue light inside the screen to the eyes. Chinese patent document CN112874100A discloses a blue light-proof and ultraviolet light-proof polyester film, a preparation method thereof, and an application thereof. The blue light-proof and ultraviolet light-proof polyester film comprises A layer, B layer, and C layer polyester films which are sequentially stacked. The A layer and the C layer polyester films each comprise the following raw materials in parts by weight: polyester chips 30-50 parts and opening agent 50-70 parts. The B layer polyester film comprises the following raw materials in parts by weight: polyester chips 70-80 parts, ultraviolet light absorber 10-15 parts, blue light-proof additive 10-15 parts, and blue light absorber 5-10 parts. The polyester film in the present application achieves the effects of preventing ultraviolet light and blue light by adding the blue light-proof additive and the ultraviolet light-proof additive in the middle layer B layer. Meanwhile, the polyester film has the effects of preventing adhesion and high light transmittance.

[0004] Existing blue light blocking optical films are basically pre-set with a filtration rate coefficient (such as 40%, 50%, or 60%). The amount of blue light blocking additives and the thickness of the film are determined based on the set filtration rate coefficient, and a film of uniform thickness with a consistent filtration rate is made in all parts. Therefore, it cannot be applied to the actual conditions of different displays at the same time, nor can it be adapted to the actual conditions of different parts of the same display at the same time.

[0005] On the other hand, Chinese patent document CN113916505A discloses a method for determining the safety threshold and safety of blue light radiation from a display. Based on determining the safety threshold for blue light radiation energy or power, a spectroradiometer is used to detect the spectral radiation power data at each detection point of the display at maximum brightness and not lower than a certain color temperature value T using appropriate methods such as the nine-point detection method. The required exposure time is calculated according to actual needs or specifications, and a wavelength-related blue light hazard weighting coefficient is introduced to calculate the blue light radiation energy or power. The blue light radiation energy or power is then compared with the corresponding safety threshold to determine whether there is a risk of blue light hazard. This method is suitable for situations where spectral radiation power is frequently used in testing during production lines or on-site applications. It simplifies the process of determining the safety of blue light radiation from various displays, including those for medical and civilian use, in industrial production or on-site applications, and provides favorable conditions for the refined design of anti-blue light optical films. Summary of the Invention

[0006] The purpose of this invention is to provide a more refined and personalized blue light blocking optical film for displays that better reflects actual conditions.

[0007] The technical solution of this invention is: a blue light blocking optical film for a display screen, wherein several sampling points are selected on the display screen, and the spectral radiant power corresponding to each sampling point is obtained based on the measured data (or detection data) of each sampling point. Based on the spectral radiant power corresponding to each sampling point, the blue light radiant energy corresponding to each sampling point is calculated using the following formula:

[0008]

[0009] The blue light radiation filtering coefficients for each sampling point (corresponding to each sampling point on the anti-blue light optical film) are assigned values ​​according to the following method:

[0010]

[0011] In the display screen coordinate system (including its equivalent coordinate system), a surface fitting is performed on the blue light radiation filtering coefficient of each sampling point (each point on the anti-blue light optical film corresponding to each sampling point) to obtain the distribution function of the blue light radiation filtering coefficient that the anti-blue light optical film should have:

[0012]

[0013] Anti-blue light optical films are prepared based on the blue light radiation filtering coefficient distribution function that anti-blue light optical films should possess.

[0014] In the above formula, This corresponds to the blue light radiation power at the sampling point. For the exposure time, The blue light radiation energy corresponding to the sampling point that poses a hazard is the product of the blue light radiation power and the exposure time. This represents the spectral radiant power corresponding to the sampling point. The wavelength-related weighting factor for blue light hazards. For wavelength, The safe threshold for blue light radiation energy. The blue light radiation filtering coefficient distribution function that the blue light blocking optical film should have. The sampling point number (the number can be...) The sampling point is denoted as the sampling point. ), For corresponding sampling points Blue light radiation energy that poses a health hazard Sampling points (On the anti-blue light optical film and at the sampling point) Assign values ​​to the blue light radiation filtering coefficient of the corresponding point. These are the coordinates in the display screen coordinate system.

[0015] Preferably, sampling points are selected according to the nine-point detection method or the 25-point detection method.

[0016] Preferably, the sampling point data is detected using spectroradiance, and the spectral radiance power corresponding to the sampling point is calculated according to the following formula:

[0017]

[0018] In the above formula, This represents the spectral radiant power corresponding to the sampling point. The sampling point and wavelength The relevant light source spectral radiance, The effective radiation source area is calculated based on the maximum opposite angle. This is the solid angle of the pupil relative to the light source.

[0019] Preferably, set .

[0020] Preferably, the anti-blue light optical film is bonded to the outermost LCD screen, or OLED screen, or MiniLED screen, or Micro LED screen.

[0021] The beneficial effects of this invention are: because Multiple measured data points were used to determine the appropriate blue light filtering coefficient for each sampling point. Based on the blue light filtering coefficient of each sampling point, a surface fitting was performed to obtain the blue light filtering coefficient distribution function of the entire blue light blocking optical film. The blue light blocking capabilities of different parts of the anti-blue light optical film are adapted to the blue light radiation conditions of different parts of the display, effectively avoiding insufficient and / or excessive filtering of local blue light, and can obtain a more refined and personalized anti-blue light optical film for the display screen that is more in line with the actual situation. Attached Figure Description

[0022] Figure 1 This is a distribution diagram on the display screen of the nine points involved in the nine-point detection method of the present invention;

[0023] Figure 2 This is the subject of the present invention. Curve graph ( curve);

[0024] Figure 3 This is a schematic diagram (cross section) of the blue light blocking optical film of unequal thickness involved in this invention.

[0025] Figure 4 This is a schematic diagram of the thickness line of the blue light filtering layer of the blue light blocking optical film with unequal thickness that relates to the present invention. Detailed Implementation

[0026] See Figures 1-4 For any specific monitor, or monitors from the same batch with good consistency produced by the factory, a spectroradiometer is used to perform multi-point detection of the spectral radiation power of the display screen. The detection can be carried out when the display screen is at its maximum brightness (design maximum brightness) or normal operating brightness, and not lower than the set color temperature value T (such as T=6000K or other color temperature values). The exposure time can be determined according to actual usage requirements or specifications (including technical standards). For example, medical monitors can typically be 28800s.

[0027] Wavelength-dependent spectral radiant power can be calculated based on measured data. ,in accordance with Weighted coefficient of known blue light hazards (recognized or standard) The blue light radiation energy (or blue light radiation power) can be calculated using the following formula (using a function):

[0028]

[0029] in,

[0030] Blue light radiation power, commonly measured in J. s -1 ;

[0031] Exposure time, commonly measured in seconds (s).

[0032] The blue light radiation power is the product of the exposure time, and can be considered as the blue light radiation energy that poses a blue light hazard. The common unit is J.

[0033] Wavelength-dependent spectral radiant power, commonly measured in J. s -1 nm -1

[0034] The wavelength-dependent weighting factor for blue light hazard (see...) Figure 2 ), dimensionless;

[0035] Wavelength, commonly measured in nm (nanometer).

[0036] Spectral radiant power can be calculated using the following formula. :

[0037]

[0038] in, The effective radiation source area (common unit: m²) is calculated based on the maximum opposite angle (0.1 rad). 2 ); The solid angle of the pupil with respect to a light source (commonly measured in sr) is related to the pupil diameter and the viewing distance, depending on the scene being observed. To match the wavelength Related light source spectral radiance (common unit: ).

[0039] The coordinates of the display screen coordinate system are ( any sampling point The blue light radiation energy and the safe threshold (set value) of blue light radiation energy will be calculated based on the detection data at this point. Compare the samples and determine the sampling points based on the comparison results. Blue light radiation filtering coefficient :

[0040] When the blue light radiation energy calculated based on the detection data at this point is not greater than the safe threshold for blue light radiation energy... ;

[0041] When the blue light radiation energy calculated based on the detection data at this point exceeds the safe threshold for blue light radiation energy... .

[0042] It can be determined based on relevant technical specifications, standards, and / or through experimental or theoretical analysis. For example, it can be based on currently recognized or appropriate standards. .

[0043] Blue light radiation filtering coefficient at each sampling point The blue light radiation filtering coefficient distribution function (data) matching the display screen size was obtained through surface fitting:

[0044]

[0045] Based on the above-mentioned filtration coefficient distribution data (function), a corresponding blue light blocking optical film is prepared.

[0046] For example, see Figure 3 and Figure 4 With the blue light filtering material remaining unchanged, the desired blue light radiation filtering coefficient can be obtained by controlling the thickness of the blue light filtering material layer 2. The blue light filtering material layer can be placed between the base layer 1 and the surface layer 3 using existing technology, or other single-layer or multi-layer structures can be adopted. The preparation method of the blue light filtering material layer and the blue light filtering optical film can employ any suitable existing technology. For example, for rigid blue light filtering materials, grinding can be used to make the thickness variation of the blue light filtering material layer conform to... The requirements; for the blue light blocking material layer formed by spraying, digital control technology can be used to control the spraying process, so that the variation in spraying thickness meets the requirements. This meets the requirements. Applying this blue light blocking optical film to the front of a display can achieve a better blue light radiation protection effect.

[0047] Further explanation regarding sampling points (detection points):

[0048] Figure 1This diagram illustrates an example of sampling points for the nine-point test method. Nine points (P0 to P8) are located on the display under test. In the diagram, h represents the height of the display screen, and w represents the width of the display screen. These nine points are arranged in 3 rows and 3 columns, forming a rectangular grid. The horizontal (width) and vertical (height) directions are evenly spaced. One point is located in the center of the display screen. The distance from the outermost point in the horizontal direction to the corresponding side of the display screen is w / 9-w / 10, and the distance from the outermost point in the vertical direction to the corresponding side of the display screen is h / 9-h / 10 (other distances can also be used depending on the actual situation, such as: the distance from the outermost point in the horizontal direction to the corresponding side of the display screen is w / 3-w / 4, and the distance from the outermost point in the vertical direction to the corresponding side of the display screen is h / 3-h / 4, etc.). Here, w is the width of the display screen (display area), and h is the height of the display screen (display area).

[0049] Depending on the needs, a 25-point detection method or other numbers of detection points can be used. The positions of the detection points are typically determined by aligning them in a rectangular grid pattern, or other suitable point selection methods can be employed to ensure that the condition of each detection point essentially reflects the condition of the display screen. For example, the points are distributed in rows and columns (e.g., the 25 points in the 25-point detection method are divided into 5 rows and 5 columns). Usually, one point is located in the exact center of the display screen (both the number of rows and columns are odd). The horizontal spacing between adjacent points is equal, and the vertical spacing between adjacent points is equal. A gap is usually left between the outermost point in both the horizontal and vertical directions and the corresponding side of the display screen. The size of this gap can adopt the corresponding gap of the aforementioned nine-point detection method, or it can be set according to actual needs or specifications.

[0050] The aforementioned rules and evenly distributed sampling points are beneficial for achieving high accuracy with less data processing. However, since this invention uses a fitting method to obtain the blue light radiation filtering coefficient distribution function, other sampling point selection methods are also permissible or effective. Sampling points should be distributed across the entire display screen, and denser sampling points can be set in areas with significant variations.

[0051] Since there is no substantial difference between a monitor and a display screen in practice when only the display screen or blue light radiation is involved, the terms "monitor," "screen," and "display screen" in this specification can refer to various monitors and displays that use the relevant display methods, including stand-alone monitors, displays, and monitors and displays integrated into or installed on other devices.

[0052] For any given exposure time, the blue light radiation energy (the product of blue light radiation power and exposure time) can be compared with a safe threshold for blue light radiation energy. When the blue light radiation energy is not greater than the safe threshold, there is no risk of blue light hazard; when the blue light radiation energy is greater than the safe threshold, there is a risk of blue light hazard. This comparison or calculation method is consistent with the conclusion reached by comparing blue light radiation power with a safe threshold. Therefore, in this invention, according to the relevant formula, the comparison or calculation method based on blue light radiation power or its threshold is equivalent to the comparison and calculation method based on blue light radiation energy or its threshold.

[0053] The safe zone or other similar expressions referred to in this invention are limited to the safety of blue light hazard risk to the human eye relative to the blue light radiation from the display during viewing. They do not involve the safety relative to other hazard methods or other hazard factors. At the same time, this safety assessment is based on existing research results or knowledge of the relevant hazards to the general population and does not involve the potential hazards to specific individuals due to individual differences and other factors.

[0054] Unless otherwise specified, the preferred and optional technical means disclosed in this invention can be arbitrarily combined to form several different specific embodiments when one preferred or optional technical means is a further limitation of another technical means.

Claims

1. A blue light blocking optical film for a display screen, characterized in that... Several sampling points are selected on the display screen. Based on the measured data of each sampling point, the spectral radiant power corresponding to each sampling point is obtained. Based on the spectral radiant power corresponding to each sampling point, the blue light radiant energy corresponding to each sampling point is calculated using the following formula: ； The blue light radiation filtering coefficient for each sampling point is assigned according to the following method: ； In the display screen coordinate system, surface fitting is performed on the blue light radiation filtering coefficient of each sampling point to obtain the distribution function of the blue light radiation filtering coefficient that the anti-blue light optical film should have: ； Anti-blue light optical films are prepared based on the blue light radiation filtering coefficient distribution function that anti-blue light optical films should possess. In the above formula, This corresponds to the blue light radiation power at the sampling point. For the exposure time, The blue light radiation energy corresponding to the sampling point that poses a hazard is the product of the blue light radiation power and the exposure time. This represents the spectral radiant power corresponding to the sampling point. The wavelength-related weighting factor for blue light hazards. For wavelength, The safe threshold for blue light radiation energy. The blue light radiation filtering coefficient distribution function that the blue light blocking optical film should have. The sampling point number, For corresponding sampling points Blue light radiation energy that poses a health hazard Sampling points The blue light radiation filtering coefficient is assigned a value. These are the coordinates in the display screen coordinate system.

2. The anti-blue light optical film for display screens as described in claim 1, characterized in that... Sampling points are selected based on the nine-point detection method or the 25-point detection method.

3. The anti-blue light optical film for display screens as described in claim 1, characterized in that... The spectral radiance was used to detect the sampling point data, and the spectral radiance corresponding to the sampling point was calculated according to the following formula: ； In the above formula, This represents the spectral radiant power corresponding to the sampling point. The sampling point and wavelength The relevant light source spectral radiance, The effective radiation source area is calculated based on the maximum opposite angle. This is the solid angle of the pupil relative to the light source.

4. The anti-blue light optical film for display screens as described in claim 1, characterized in that... set up .

5. The anti-blue light optical film for display screens as described in claim 1, characterized in that... The blue light blocking optical film is applied to the outermost LCD screen, OLED screen, MiniLED screen, or Micro LED screen.

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