Anti-blue light lens containing perovskite quantum dots

Abstract

The invention provides an anti-blue-light lens containing perovskite quantum dots. The anti-blue-light lens at least comprises a base material and the perovskite quantum dots dispersed in the base material, the chemical formula of the perovskite quantum dot is CsPb (BrCl) 3: Sr, wherein Sr is strontium ions doped into perovskite crystal lattices; the emission peak of the perovskite quantum dot is located in the wave band range of 480-510 nm, the half-peak width is not larger than 25 nm, and harmful blue light in the wave band of 415-445 nm can be absorbed and subjected to light conversion; in addition, the perovskite quantum dots also generate a synergistic absorption effect on part of red light and green light in transmission light, so that three primary colors of red, green and blue are synchronously attenuated, thereby reducing lens yellow color cast caused by blue light reduction, and realizing consideration of blue light prevention performance and visual color balance.

Description

Technical Field

[0001] This invention belongs to the field of perovskite quantum dot preparation technology, and particularly relates to a blue light blocking lens containing perovskite quantum dots. Background Technology

[0002] With the widespread use of electronic display devices, prolonged exposure of the human eye to high-energy blue light, primarily emitted by LEDs, can easily lead to visual fatigue, dry eyes, and other discomforts. Furthermore, under prolonged or high-intensity conditions, it can increase the risk of macular damage to the retina. Therefore, blue light blocking lenses, as an important vision protection product, are widely used in daily life and office settings.

[0003] like Figure 1 As shown, traditional blue light blocking lenses typically achieve their protective purpose by introducing blue light blocking agents or other blue light blocking factors into the lens substrate to selectively absorb harmful blue light in the 415–445 nm wavelength band, thereby reducing the transmittance of blue light in this band. However, this type of blue light blocking solution based on absorption mechanism has unavoidable limitations in practical applications, namely, the overall lens tends to exhibit a yellowish tint.

[0004] From a spectral perspective, the perception of colorless transparency stems from the combined effect of blue, green, and red light in a certain proportion on the human eye. When traditional blue light blocking lenses selectively absorb short-wavelength blue light in the 415–445 nm band by adding light-absorbing agents, they do not absorb green and red light. This significantly reduces the short-wavelength blue light component in the transmission spectrum, while increasing the relative proportion of mid- and long-wavelength components. With reduced blue light stimulation, the human eye perceives the remaining transmitted light, primarily green and red, as yellowish or warm (yellow can be considered a composite color of red and green light), thus visually appearing as an overall yellowish tint to the lens. Research shows that while increasing the amount of light-absorbing agent can improve the absorption intensity of harmful blue light, it also exacerbates the yellowish shift of the lens.

[0005] However, a yellowish tint in lenses alters the spectral structure of the light entering the eye, leading to a series of adverse effects. These include a warmer appearance of white objects, reduced ability to recognize short-wavelength colors such as blue and purple, and color distortion in display screens. These problems are particularly pronounced in applications requiring high color accuracy and reproduction, such as design, medicine, image analysis, and driving. From an optical design perspective, absorptive blue light blocking lenses essentially sacrifice color fidelity for blue light reduction. On the other hand, while keeping the amount of light-absorbing agent low can reduce the yellow tint to some extent, it limits the ability to block harmful blue light, making it difficult to simultaneously achieve both protective performance and a good visual experience. Therefore, improvements are urgently needed. Summary of the Invention

[0006] The purpose of this invention is to provide a blue light blocking lens containing perovskite quantum dots. Through the synergistic effect of spectral conversion and absorption, it can effectively reduce the transmission of harmful blue light in the 415–445 nm band while compensating for the beneficial blue light components in the 445–505 nm band. It improves the transmission spectrum balance from multiple angles, reduces the yellow color cast of the lens, and achieves a balance between protective performance and visual experience.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is: a blue light blocking lens containing perovskite quantum dots, wherein the blue light blocking lens comprises at least a matrix material and perovskite quantum dots dispersed in the matrix material; the chemical formula of the perovskite quantum dots is CsPb(BrCl)3:Sr; Sr represents strontium ions that are doped into the perovskite lattice; The emission peak of the perovskite quantum dot is located in the 480–510 nm wavelength range, and the half-width is no more than 25 nm, which can absorb and convert harmful blue light in the 415–445 nm wavelength range. The perovskite quantum dots also synergistically absorb some of the red and green light in the transmitted light, causing the three primary colors of red, green, and blue to attenuate synchronously. This reduces the yellow color cast on the lens caused by blue light reduction, achieving a balance between blue light protection and visual color balance.

[0008] As is well known in the field, blue light can be divided into harmful blue light and beneficial blue light. Among them, blue light in the 415–445 nm wavelength band has high energy and strong penetrating power, and long-term exposure may cause damage to the macula of the retina, thus it is considered harmful blue light; while blue light in the 445–505 nm wavelength band (especially the approximately 495 nm band) plays an important role in regulating circadian rhythms, maintaining wakefulness, and inhibiting melatonin secretion, and should not be excessively blocked.

[0009] The blue light blocking lens of this invention not only effectively reduces blue light in the 415–445 nm wavelength range, but also ensures high transmittance of blue light in the 445–505 nm wavelength range and converts some harmful blue light into beneficial blue light. Furthermore, the perovskite quantum dots in the lens synergistically absorb some red and green light in the transmitted light, causing synchronous attenuation of the red, green, and blue primary color signals. This reduces the yellow tint of the lens caused by blue light reduction, achieving a balance between blue light blocking performance and visual color balance.

[0010] Furthermore, the emission peak of the perovskite quantum dots of the present invention is 495 nm.

[0011] Furthermore, the lens substrate material is selected from one of resin materials, optical plastics, and inorganic glass.

[0012] Furthermore, the perovskite quantum dots are inorganic perovskite quantum dots obtained through high-temperature solid-state reaction combined with mesoporous encapsulation and water washing post-treatment, and their exterior has a coating structure composed of inorganic mesoporous materials.

[0013] Furthermore, the blue light blocking lens also contains a light absorber, which is dispersed together with perovskite quantum dots in the lens matrix material to synergistically regulate the transmission spectrum of the lens.

[0014] Furthermore, the light absorber absorbs at least harmful blue light in the 415–445 nm wavelength band; The perovskite quantum dots are used to weakly absorb the remaining blue light and some red and green light after absorption by the light absorber, so that the red, green and blue primary color signals are attenuated synchronously. Through the synergistic effect of perovskite quantum dots and light absorbers, the transmittance of harmful blue light in the 415–445 nm band is reduced, while the yellow tint of the lens is mitigated and natural visual colors are maintained.

[0015] Furthermore, the light absorber is selected from organic light absorbers, inorganic light absorbers, or combinations thereof; The organic light-absorbing agent is selected from one of benzotriazoles, benzophenones, thiazides, or their derivatives; The inorganic light absorber is selected from one of transition metal oxides and rare earth oxides.

[0016] Furthermore, the amount of perovskite quantum dots added to the lens is greater than the amount of light absorber added.

[0017] Furthermore, the amount of perovskite quantum dots added is at least twice that of the light absorber.

[0018] Furthermore, the perovskite quantum dots are prepared by the following method: S1. Mix CsBr, PbCl2, KBr and SrCl2 to obtain the sintering precursor; S2. The sintering precursor is mixed and ground with nano-alumina, mesoporous molecular sieve and calcium hydroxide to obtain a mixture. Then the mixture is placed in a sintering device and heated to 500-600℃ for calcination. After holding at the temperature, it is naturally cooled and then washed and dried to obtain perovskite quantum dots.

[0019] The beneficial effects of this invention are mainly reflected in: (1) This invention utilizes the absorption and spectral conversion of high-energy blue light in the 415–445 nm wavelength band by perovskite quantum dots, combined with the selective suppression of harmful blue light in the 415–445 nm wavelength band by light absorbers, to avoid excessive reduction of beneficial blue light components. At the same time, the emission peak of perovskite quantum dots is 495 nm, which allows perovskite quantum dots to convert some harmful blue light into beneficial blue light, thereby supplementing the beneficial blue light.

[0020] (2) The perovskite quantum dots added to the lens of the present invention synergistically absorb some red and green light, causing the red, green and blue primary color signals to attenuate synchronously, avoiding serious imbalance of the proportion of the three primary colors from the spectral level, effectively improving the yellow color distortion phenomenon that is common in existing anti-blue light lenses, and improving visual naturalness and comfort.

[0021] (3) This invention achieves a composite blue light protection mechanism of "spectral conversion + absorption modulation" through the synergistic effect of perovskite quantum dots and light absorbers. Compared with single absorption-type blue light protection schemes, the spectral control has a higher degree of freedom and can adapt to different protection levels and visual needs. Attached Figure Description

[0022] Figure 1 For existing blue light blocking glasses; Figure 2 From top to bottom, the images show the appearance of the lenses prepared in Comparative Example 2, Example 2, and Comparative Example 1 of this invention. Figure 3 These are spectral comparison diagrams of Embodiment 2 and Comparative Examples 1-2 of the present invention; Figure 4 This is a spectral diagram showing the synchronous attenuation of blue, green, and red primary color signals by the perovskite quantum dots prepared in Example 1 of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0024] Example 1: A method for preparing perovskite quantum dots includes the following steps: Step 1: Mix CsBr (8.5g), PbCl2 (6.652g), KBr (1.75g) and SrCl2 (1.253g) using a stirrer for 60s to obtain the sintering precursor; Step 2: The sintering precursor from Step 1, nano-alumina (3.27g), MCM-41 (50g), calcium hydroxide (5.602g), and zirconium oxide (5g) were mixed in a 1L mill at 300 rpm for 1 hour to obtain a mixture. Step 3: Place the mixture from Step 2 into a muffle furnace and calcine it at 570℃ at a rate of 10℃ / min, hold it at that temperature for 30 min, and then allow it to cool naturally. Finally, bluish-green perovskite quantum dots with a wavelength of 495nm, a full width at half maximum (FWHM) of 17nm, a luminous efficiency of 60%, and a D90 of 20μm are obtained.

[0025] Example 2: The preparation of blue light blocking lenses includes the following steps: The 495nm perovskite quantum dot powder and 450nm light absorber prepared according to Example 1 were mixed with PC masterbatch, and then put into a pulverizer for thorough mixing and pulverization. After being added to an extruder for high-temperature hot extrusion, a blue light blocking lens was obtained. The amount of perovskite quantum dot powder added is 0.05% of the mass of PC masterbatch.

[0026] The amount of the 450nm light absorber added is 0.5 parts per ten thousand of the PC masterbatch mass; In this embodiment, the light absorber used is VIS450 light absorber from Shanghai Chenlai Chemical Technology Co., Ltd.

[0027] Comparative Example 1: The difference from Example 2 is that no 450nm light absorber was added, but perovskite quantum dot powder was still added; otherwise, it was the same as Example 2. Testing showed that the blue light intensity reduction percentage was only 7.07%.

[0028] Comparative Example 2: The difference from Example 2 is that perovskite quantum dot powder is not added, but a 450nm light absorber is still added; otherwise, it is the same as Example 2.

[0029] The amount of the 450nm light absorber added is 0.5 parts per ten thousand of the PC masterbatch mass.

[0030] Comparative Example 3: The difference from Example 2 is that no 450nm light absorber or perovskite quantum dot powder is added.

[0031] Comparative Example 4: The difference from Comparative Example 1 is that the perovskite quantum dots of this invention are replaced with 495nm quantum dots prepared by ball milling (CN119907380A) prepared by our company in a previous application. The surface of the quantum dots prepared by ball milling is not coated with the mesoporous material MCM-41, and therefore they are prone to failure during high-temperature hot extrusion in an extruder. Testing showed that the blue light intensity reduction percentage was only 0.5%.

[0032] Figure 3 The spectral irradiance of a blue light source (nominal wavelength 450 nm) was measured using an HP350L spectrophotometer. The instrument directly outputs the unit as μW / (cm²).2 Spectral irradiance data in nm. The data were converted to mW / (m 2 After ·nm), numerical integration is performed in the 380–780 nm band to obtain the total irradiance (mW / m). 2 ),Right now Figure 3 The vertical axis unit is total irradiance (mW / m 2 ).

[0033] Depend on Figure 3 It can be seen that the blue light intensity of the blank control group (Comparative Example 3) without the addition of perovskite quantum dots and light absorbers is 192.87485 mW / m. 2 After adding the light absorber, the blue light intensity was 95.43411 mW / m². 2 If perovskite quantum dots are further added, the blue light intensity reaches 50.24189 mW / m². 2 This reduced the intensity of harmful blue light by 73.95%. At the same time, we found that after adding perovskite quantum dots, some of the harmful blue light was converted into beneficial blue light, thus compensating for the lack of blue light in the projected light.

[0034] To test the absorption intensity of blue, green, and red light by the perovskite quantum dots of this invention, the following experimental method was constructed: A. The UV resin was removed and dispersed using a dispersion disc for 0.5 hours. After ultrasonic defoaming for 10 minutes, it was evenly coated onto the micro-projection light-emitting panel using a coating process. The measured values ​​were: blue peak intensity 0.0396, green peak intensity 0.0218, and red peak intensity 0.0274.

[0035] B. Add perovskite quantum dot powder with a wavelength of 495nm from Example 1 to an equal amount of UV resin in step A above at a ratio of 0.05%. Disperse the mixture using a dispersion disc for 0.5 hours, and then defoam using ultrasound for 10 minutes. Finally, apply the mixture evenly to a micro-projection backlight panel using a coating process. The measured blue light peak intensity was 0.0368 mW / m. 2 The green peak intensity is 0.0208 mW / m 2 The intensity of the red peak is 0.0264 mW / m 2 .

[0036] This data comparison reveals that adding the 495nm perovskite quantum dots of this invention reduces blue light intensity by 0.0028 mW / m. 2 The percentage was 7.07%, and the green light intensity decreased by 0.001 mW / m. 2 The percentage is 4.5%, and the red light intensity decreases by 0.001 mW / m. 2The percentage is 3.74%. This further proves that the perovskite quantum dots added to the lens synergistically absorb some red and green light, causing the red, green, and blue primary color signals to attenuate synchronously. This avoids a serious imbalance in the proportion of the three primary colors at the spectral level, effectively improving the yellow color cast phenomenon that is common in existing blue light blocking lenses, and improving visual naturalness and comfort.

[0037] Finally, combining Figure 2 It can be seen that both Example 2 and Comparative Example 2 of this invention use the same concentration of light-absorbing agent, but the resulting lens colors are significantly different. This invention uses a light-absorbing agent to absorb harmful blue light in the 415–445 nm wavelength band within the lens; perovskite quantum dots are used to weakly absorb the remaining blue light and some red and green light after absorption by the light-absorbing agent, causing the red, green, and blue primary color signals to attenuate synchronously; through the synergistic effect of perovskite quantum dots and the light-absorbing agent, the transmittance of harmful blue light in the 415–445 nm wavelength band is reduced while mitigating the yellow tint of the lens and maintaining natural visual color.

[0038] The present invention has been illustrated with the above embodiments to explain the detailed preparation method of the present invention. However, the present invention is not limited to the above detailed preparation method, that is, it does not mean that the present invention must rely on the above product and detailed preparation method to be implemented. Those skilled in the art should understand that any improvement to the present invention, or the combination or equivalent substitution of the raw materials of the present invention, falls within the protection scope and disclosure scope of the present invention.

Claims

1. An anti-blue light lens containing perovskite quantum dots, characterized in that, The blue light blocking lens comprises at least a matrix material and perovskite quantum dots dispersed in the matrix material; the chemical formula of the perovskite quantum dots is CsPb(BrCl)3:Sr; Sr represents strontium ions that are doped into the perovskite lattice; The emission peak of the perovskite quantum dot is located in the 480–510 nm wavelength range, and the half-width is no more than 25 nm, which can absorb and convert harmful blue light in the 415–445 nm wavelength range. The perovskite quantum dots also synergistically absorb some of the red and green light in the transmitted light, causing the three primary colors of red, green, and blue to attenuate synchronously. This reduces the yellow color cast on the lens caused by blue light reduction, achieving a balance between blue light protection and visual color balance.

2. The anti-blue light lens containing perovskite quantum dots according to claim 1, wherein, The lens substrate material is selected from one of resin materials, optical plastics, and inorganic glass.

3. The anti-blue light lens containing perovskite quantum dots according to claim 1, wherein, The perovskite quantum dots are inorganic perovskite quantum dots obtained through high-temperature solid-state reaction combined with mesoporous encapsulation and water washing post-treatment, and their exterior has a coating structure composed of inorganic mesoporous materials.

4. The anti-blue light lens containing perovskite quantum dots according to claim 1, wherein, The blue light blocking lens also contains a light absorber, which is dispersed together with perovskite quantum dots in the lens matrix material to synergistically regulate the lens's transmission spectrum.

5. The anti-blue light lens containing perovskite quantum dots according to claim 4, wherein, The light absorber absorbs at least the harmful blue light in the 415–445 nm wavelength range; The perovskite quantum dots are used to weakly absorb the remaining blue light and some red and green light after absorption by the light absorber, so that the red, green and blue primary color signals are attenuated synchronously. Through the synergistic effect of perovskite quantum dots and light absorbers, the transmittance of harmful blue light in the 415–445 nm band is reduced while mitigating yellow tint in the lens and maintaining natural visual color.

6. The anti-blue light lens containing perovskite quantum dots according to claim 5, wherein, The light absorber is selected from organic light absorbers, inorganic light absorbers, or combinations thereof; The organic light-absorbing agent is selected from one of benzotriazoles, benzophenones, thiazides, or their derivatives; The inorganic light absorber is selected from one of transition metal oxides and rare earth oxides.

7. The anti-blue light lens containing perovskite quantum dots according to claim 5, wherein, The amount of perovskite quantum dots added to the lens is greater than the amount of light absorber added.

8. A blue light blocking lens containing perovskite quantum dots according to claim 7, characterized in that, The amount of perovskite quantum dots added is at least twice that of the light absorber.

9. A blue light blocking lens containing perovskite quantum dots according to any one of claims 1-7, characterized in that, The perovskite quantum dots were prepared by the following method: S1. Mix CsBr, PbCl2, KBr and SrCl2 to obtain the sintering precursor; S2. The sintering precursor is mixed and ground with nano-alumina, mesoporous molecular sieve and calcium hydroxide to obtain a mixture; then the mixture is placed in a sintering device and heated to 500-600℃ for calcination, and after holding at the temperature, it is naturally cooled to obtain perovskite quantum dots.

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