Blue-light Blocking Research Articles

Comparison of Blue Light Blocking Effects of Tips and Tinted Lenses for Dental Light Curing Machines

Background/Objectives: This study aimed to examine the blue-light blocking effect according to the curing light tip and the color of the protective eyeglass lens for the operator’s eye protection.Method/Statistical Analysis: The transmittance of light with a wavelength between 200 and 900 nm was measured three times at 1.8 nm intervals using a UV-vis spectrophotometer (LAMBDA 265, Perkinelmer, Inc.). Then the average values obtained were compared for analysis. The visible- and blue-light transmittances of all the tips and tinted lenses were examined, and the ratios of blue light in the transmitted visible light were analyzed to compare the blue-light blocking effects.Findings: The transmittance of visible light with a wavelength between 380 and 750 nm was highest in the yellow lens (60.58%), followed by company B’s tip (55.23%), company A’s tip (51.46%), the orange lens (47.48%), company C’s tip (41.53%), and the red lens (41.00%). The blue-light transmittance was 0.14% in company A’s tip for the curing light gun, 0.75% in company B’s tip, and 0.12% in company C’s tip, which were all very low. Among the tinted lenses, the orange lens had the lowest blue-light transmittance (0.20%), the red lens had a blue-light transmittance of 6.59%, and the yellow lens had the highest blue-light transmittance (12.53%). For the analysis results of the ratio of blue light in the transmitted visible light, it was 0.27% for company A’s tip, the best blue-light blocking rate, and 20.68% for the yellow lens, the worst blue-light blocking rate. The ratios of blue light in the transmitted visible light for companies B and C’s tips were 1.35 and 0.29%, respectively, showing that they have a good blue-light blocking effect.Improvements/Applications: The curing light tips and orange lens used for the analyses in this study showed a blue-light blocking effect. In the case of blue-light blocking by tinted lenses, further studies are required because the blocking rate may vary depending on the lens tint concentration.

Qualitative and Quantitative Analysis of Blue Light Blocking Effect

Purpose : A new method of quantitatively analyzing the effects of blue light blocking lenses was proposed and applied to a commercially available functional lens. Methods : The light transmittance of the lens was measured and qualitative analysis of the efficiency was performed by applying the blue light blocking efficiency function. In addition, a new quantitative analysis method for integrating and quantifying blue light blocking efficiency results was introduced, and applied to commercially available blue light blocking functional lenses for comparative analysis. Results : As a result of applying qualitative analysis method to general lens, two lenses manufactured by coating method and one lens manufactured by coloring method, all lenses were found to have excellent effect of blocking light in short wavelength region. However, the results of the quantitative analysis method confirmed that there is a slight difference for each lens. Conclusion : As the optical characteristics of various display devices and smartphones are evolving and changing day by day, optical characteristics analysis of light sources and optical products is required in various ways. Accordingly, the new quantitative analysis method introduced in this study was confirmed to be an effective means.

Blue light blocking glasses and CBT-I: effect on subjective and objective sleep quality

Blue light blocking glasses and CBT-I: effect on subjective and objective sleep quality

Augmenting CBT-I with blue-light blocking glasses improves anxiety in insomnia patients

Augmenting CBT-I with blue-light blocking glasses improves anxiety in insomnia patients

코팅 청색광 차단 렌즈의 설계와 청색광 차단율에 따른 광학적 특성 연구

코팅 청색광 차단 렌즈의 설계와 청색광 차단율에 따른 광학적 특성 연구

The Protective Effects of Blue Light-Blocking Films With Different Shielding Rates: A Rat Model Study.

PurposeTo examine light emitting diode (LED)-induced retinal photochemical damage and assess the protective performance of blue light-shielding films with different shielding rates in Sprague-Dawley rats (SD rats).MethodsSD rats were randomly divided into five groups: blank control (group I), white LED illumination (group II), and white LED illumination combined with shielding of blue light of wavelength 440 nm at 40%, 60%, and 80% (groups III, IV, and V). The illumination was 200 lux. All animals underwent electroretinography (ERG), hematoxylin-eosin (H&E) staining, immunohistochemical (IHC) staining, and transmission electron microscopy (TEM) observation after 14 days of dark-adaptation before illumination, after 14 days of cyclic illumination, and after 14 days of darkness for recovery following illumination.ResultsERG showed retinal functional loss after LED light exposure. However, retinal cell function was partly recovered after a further 2 weeks of dark adaptation. H&E staining and TEM revealed increases in photoreceptor cell death after illumination. IHC staining demonstrated that oxidative stress was associated with retinal injury. Although retinal light injury was discovered in the LED light-exposure groups, shielding 60% of blue light of wavelength 440 nm (bandwidth 20 nm) protected retinas.ConclusionsCyclic illumination of low light intensity (200 lux) for 14 days produced retinal degeneration; shielding 60% of blue light may protect retinas from light damage.Translational RelevanceThis study found the effective shielding rate that could protect retinas from light damage when shielding specific narrow-band harmful blue light; thus providing a more normative method for protecting eyes from blue light hazard.

Polarized glasses may help in symptomatic cases of intraocular lens glistenings.

Intraocular lens (IOL) glistening is a relatively common phenomenon. Although most of the patients remain asymptomatic, a small percentage of patients can develop unwanted optical side effects. We report 6 symptomatic patients with IOL glistening. All patients underwent an implantation of a hydrophobic acrylic mononofocal, multifocal or toric IOL in external clinics for visually significant cataract at least 6 months prior. Patients had very reasonable corrected visual acuity (0.8–1.0 decimal), but significantly had reduced contrast sensitivity and modulation transfer function, complained of visual phenomena and expressed dissatisfaction with their visual status. Patients indicated the symptoms were not present immediately after surgery, but gradually developed postoperatively. Slit-lamp examination revealed moderate-to-severe glistening in all cases. No other pathology that would be responsible for the visual symptoms was present. Patients reported improvement in side effects with the use of edge filter (blue-light blocking) eyeglasses and polarized sunglasses with an increase in contrast sensitivity by aproximately 1 line on Pelli–Robson chart. The use of specific eyewear seems to be a promising alternative to avoid explant of an IOL in symptomatic patients with glistenings and very good visual acuity. In conclusion, we believe that long-term optical clarity is crucial for the choice of an IOL.

Protective effects of blue light-blocking shades on phototoxicity in human ocular surface cells

ObjectiveBlue light hazards for retina and ocular surface have been repeatedly described and many protective methods are introduced for retina; however, no study has been conducted on ocular surface protection....

Insights into Australian optometrists' knowledge and attitude towards prescribing blue light-blocking ophthalmic devices.

The aim of this cross-sectional study was to survey Australian optometrists regarding their attitudes towards, and knowledge of, blue light-blocking lenses designed to attenuate blue light transmission to the eye. A 29-item survey was distributed at a major national optometry education conference and through professional networks. Respondents provided information regarding their demographics and practice modalities, knowledge about the potential effects of blue light, and attitudes towards prescribing blue light-blocking ophthalmic devices. Ordinal logistic regression analysis was performed to assess the factors that predicted optometrists' prescribing of blue light-blocking lenses. Of 372 respondents, 75.3% indicated prescribing blue light-blocking spectacle lenses in their clinical practice. Forty-four per cent of optometrists considered daily environmental exposure to blue light as a potential cause of retinal damage, and approximately half of respondents thought blue light emitted from computer screens was an important factor in causing computer vision syndrome. About half of optometrists considered placebo effects to potentially play a role, at least sometimes, in patients' experiences with blue light-blocking lenses. Most optometrists estimated that they first prescribed a blue light-blocking lens in 2016. The most common reason optometrists prescribed these devices was for patients who were computer or electronic device users (87.9%). The two main sources of information used to guide practitioners' management approaches were conference presentations and manufacturer product information. Practitioners were significantly more likely to prescribe blue light-blocking lenses if they considered blue light to cause either retinal damage (odds ratio, OR 2.28, 95%CI 1.34-3.88, p=0.002) or computer vision syndrome (OR 2.52, 95%CI 1.41-4.50, p=0.002) compared with practitioners who did not consider such factors to be relevant. Prescribing trends by Australian optometrists in relation to blue light-blocking lenses reflect the inconclusive nature of several aspects of the evidence in this field. Blue light-blocking lens prescribing has increased since 2010, despite practitioners acknowledging the lack of high-quality evidence to support their use and also commonly believing that placebo effects may have a role in patient responses to these lenses. Information from this study will help inform the development of resources to guide evidence-based prescribing of blue light-blocking lens products.

스마트 기기로 바탕색이 다른 근거리작업 시 청광차단렌즈가 가독성 및 자각 증상에 미치는 영향

스마트 기기로 바탕색이 다른 근거리작업 시 청광차단렌즈가 가독성 및 자각 증상에 미치는 영향

Ultraviolet to blue blocking and wavelength convertible films using carbon dots for interrupting eye damage caused by general lighting

Our eyes are regularly exposed to ultraviolet (UV) and blue light emitting diode (LED) light-based devices. However, the blue light induces macular degeneration, optic nerve crush, eye strain, and increases reactive oxygen species, which negatively influence eye-related cells (photoreceptor and retinal pigmented epithelial cells). UV light is also harmful to humans. It induces photokeratitis, cataract, and ocular surface squamous neoplasia. Here, we present carbon dot films with different carbon dot contents, prepared by a simple method. The films exhibit strong UV and blue light absorption. The transmittance of carbon dot films is >70% in the visible region (>500 nm). The UV light blocking ratio of commercial blue blocking filter and carbon dot film using UV LED chips is 94.1% and 95.9% (40 wt%), respectively. The blue light blocking ratio of commercial blue blocking filter and carbon dot film using blue LED chips is 10.2% and 82.3% (40 wt%), respectively. These results indicate that the prepared carbon dot films have a UV blocking rate similar to that of commercial blue blocking filters and a much better blue blocking rate than commercial blue blocking filters. Therefore, they can be effectively used as UV and blue blocking films in various applications.

스마트폰 조명에 의한 망막내의 Lipofuscin인 A2E의 광산화 효과와 청색광 차단 렌즈에 의한 광산화 방지효과

스마트폰 조명에 의한 망막내의 Lipofuscin인 A2E의 광산화 효과와 청색광 차단 렌즈에 의한 광산화 방지효과

스마트 기기로 바탕색이 다른 근거리 작업 시 청광 차단 렌즈가 조절 기능에 미치는 영향

스마트 기기로 바탕색이 다른 근거리 작업 시 청광 차단 렌즈가 조절 기능에 미치는 영향

Cesium lead halide perovskite nanocrystals for ultraviolet and blue light blocking

Using cesium lead halide perovskite nanocrystals, CsPb(Cl/Br)3, as a light absorber, we report a highly effective UV and blue light blocking film. The CsPb(Cl/Br)3 nanocrystals are well dispersed in the ethyl cellulose (EC) matrix to compose a UV and blue light shielding film, and the absorption edge of the film is tunable by adjusting Cl to Br ratio using anion exchange. The CsPbCl2Br-EC film exhibits a transmittance of 5% at 459 nm, 90% at 478 nm and 95% in the range of 500–800 nm, which makes it excellent for UV and blue light shielding. In addition, the as-prepared EC-CsPb(Cl/Br)3 film shows excellent photostability under UV irradiation. Results demonstrate that this EC-CsPb(Cl/Br)3 based materials with sharp absorbance edges, tunable blocking wavelength, and high photostability can be useful for the applications in UV and blue light blocking and optical filters

Effects of color lenses on visual evoked magnetic fields following bright light.

Photophobia is a common condition in which bright light causes an unpleasant feeling due to increased sensitivity to light. In addition to discomfort, photophobia may be accompanied by visual dysfunction. The present study was conducted in order to examine whether visual evoked cortical responses contribute to the assessment of visual dysfunction due to bright light. Visual evoked magnetic fields (VEFs) following the presentation of a uniform bright light of 200–3700 cd/m2 in the lower visual field were recorded in 10 healthy volunteers and the effects of five color lenses: yellow, blue, gray, green, and colorless, were examined. VEFs were subjected to a multi-dipole analysis that resulted in the separation of several source activities, including the retina, V1, V2, V6, and fusiform gyrus. Source activity in the retina corresponding to the ERG b-wave exhibited a reduced amplitude and elongated peak latency with the yellow lens. Its latency strongly correlated with transmittance at 450 nm. On the other hand, cortical activities in V1 and the fusiform gyrus were stronger with the yellow lens than with the other color and colorless lenses. Only blue-light blocking showed significant effects. The result showing that the yellow lens enhanced V1 and fusiform activities indicated that processing in these areas was improved when subjects used this lens. The combination of delayed retinal activity and increased visual cortex activity may be an objective indicator of the effects of a color lens on visual function.

자외선 차단제의 블루라이트 차단효과에 관한 연구

Blue light is the highest energy wavelengths in the visible light region and induces skin aging and active oxygen. Studies on harmful mechanism of skin are under way. Research on blue light blocking materials in cosmetics and formulation studies are in the early stage, and the test methods related to blue light blocking measurement are not established. The blue light blocking efficacy was established by referring to the test method of the sunscreen in vitro test(COLIPA guideline, ISO 24443, FDA Final Rule on Sunscreen Testing and Labeling). The blue light blocking effect was evaluated for 17 kinds out of 27 kinds of sunscreen raw materials suggested in KFDA guideline. The Effect was 14.97% for zinc oxide and 16.32% for bishexyloxyphenol methoxyphenyl triazine, 35.47% for methylene bis-benzotriazolyltetramethylbutylphenol, and 65.96% for titanium dioxide. In addition, the effect of micro-titanium dioxide was twice as high as that of the nano-titanium dioxide. The results suggested that the light blocking effect test method can be used to search for blue light blocking materials and study cosmetic formulations.

Evaluation of the impact of a new selective blue light filter and class 1 UV blocking SiHy lens (75% WC) examining contrast sensitivity and colour perception

Purpose: Changes in lifestyles and the exposure, both at work and leisure time, to smartphones, tablets, screens and led illumination, has raised concerns about the potential harmful effects of blue light. The purpose of this study is to evaluate the impact of a new blue light and UV blocking silicone hydrogel lens measuring contrast sensitivity and colour perception, under photopic and mesopic conditions, and to compare it with same material with no filters.

Development of functional spectacle lens with Photo-Discoloration and ultraviolet blocking function

The photochromic layer is disposed at the outermost periphery, and then the ultraviolet light blocking layer and the blue light blocking layer are disposed inward. The photo-discoloration requires ultraviolet rays, but the ultraviolet blue light blocking layer does not require ultraviolet rays, so the two layers must be separated. Ultraviolet rays of 410 nm or less were completely blocked, and blue light showed a blocking rate of about 40% in the range of 380 nm to 500 nm. The discoloration required 0.5 seconds and 3 seconds, respectively, in the light reaction. Photochromic spectacle lenses are generally used as in sunglasses in outdoors. This is a very useful item because it effectively blocks ultraviolet and blue light.

Analysis of Optical Performance in Blue Light Blocking Lenses

Analysis of Optical Performance in Blue Light Blocking Lenses

Blue-light filtering alters angiogenic signaling in human retinal pigmented epithelial cells culture model

BackgroundLight exposure and more specifically the spectrum of blue light contribute to the oxidative stress in Age-related macular degeneration (AMD). The purpose of the study was to establish whether blue light filtering could modify proangiogenic signaling produced by retinal pigmented epithelial (RPE) cells under different conditions simulating risk factors for AMD.MethodsThree experiments were carried out in order to expose ARPE-19 cells to white light for 48 h with and without blue light-blocking filters (BLF) in different conditions. In each experiment one group was exposed to light with no BLF protection, a second group was exposed to light with BLF protection, and a control group was not exposed to light. The ARPE-19 cells used in each experiment prior to light exposure were cultured for 24 h as follows: Experiment 1) Normoxia, Experiment 2) Hypoxia, and Experiment 3) Lutein supplemented media in normoxia. The media of all groups was harvested after light exposure for sandwich ELISA-based assays to quantify 10 pro-angiogenic cytokines.ResultsA significant decrease in angiogenin secretion levels and a significant increase in bFGF were observed following light exposure, compared to dark conditions, in both normoxia and hypoxia conditions. With the addition of a blue light-blocking filter in normoxia, a significant increase in angiogenin levels was observed. Although statistical significance was not achieved, blue light filters reduce light-induced secretion of bFGF and VEGF to near normal levels. This trend is also observed when ARPE-19 cells are grown under hypoxic conditions and when pre-treated with lutein prior to exposure to experimental conditions.ConclusionsFollowing light exposure, there is a decrease in angiogenin secretion by ARPE-19 cells, which was abrogated with a blue light - blocking filter. Our findings support the position that blue light filtering affects the secretion of angiogenic factors by retinal pigmented epithelial cells under normoxic, hypoxic, and lutein-pretreated conditions in a similar manner.