Department of Experimental Psychology, University of Oxford, Oxford, UK.
Centre for Chronobiology, Psychiatric Hospital of the University of Basel (UPK), Basel, Switzerland.
Ophthalmic Physiol Opt. 2019 Nov;39(6):459-468. doi: 10.1111/opo.12648.
Optical filters and tints manipulating short-wavelength light (sometimes called 'blue-blocking' or 'blue-attenuating' filters) are used in the management of a range of ocular, retinal, neurological and psychiatric disorders. In many cases, the only available quantification of the optical effects of a given optical filter is the spectral transmittance, which specifies the amount of light transmitted as a function of wavelength.
We propose a novel physiologically relevant and retinally referenced framework for quantifying the visual and non-visual effects of these filters, incorporating the attenuation of luminance (luminous transmittance), the attenuation of melanopsin activation (melanopsin transmittance), the colour shift, and the reduction of the colour gamut (gamut reduction). Using these criteria, we examined a novel database of spectral transmittance functions of optical filters (n = 121) which were digitally extracted from a variety of sources.
We find a large diversity in the alteration of visual and non-visual properties. The spectral transmittance properties of the examined filters vary widely, in terms of shapes and cut-off wavelengths. All filters show relatively more melanopsin attenuation than luminance attenuation (lower melanopsin transmittance than luminous transmittance). Across the data set, we find that melanopsin transmittance and luminous transmittance are correlated.
We suggest that future studies and examinations of the physiological effects of optical filters quantify the visual and non-visual effects of the filters beyond the spectral transmittance, which will eventually aid in developing a mechanistic understanding of how different filters affect physiology. We strongly discourage comparing the downstream effects of different filters on, e.g. sleep or circadian responses, without considering their effects on the retinal stimulus.
光滤光片和镜片可调节短波长光（有时称为“蓝光阻断”或“蓝光衰减”滤光片），用于治疗多种眼部、视网膜、神经和精神疾病。在许多情况下，给定光滤光片的光学效果的唯一可用量化指标是光谱透过率，它指定了光随波长传输的量。
我们提出了一种新的生理相关和视网膜参考框架，用于量化这些滤光片的视觉和非视觉效果，包括亮度衰减（光透过率）、黑视素激活衰减（黑视素透过率）、色移和色域减少（色域减少）。使用这些标准，我们检查了一个新的光滤光片光谱透过率函数数据库（n=121），这些函数是从各种来源数字提取的。
我们发现视觉和非视觉特性的改变有很大的差异。所检查的滤光片的光谱透过率特性在形状和截止波长方面变化很大。所有滤光片显示出相对更多的黑视素衰减而不是亮度衰减（黑视素透过率低于光透过率）。在整个数据集内，我们发现黑视素透过率和光透过率相关。
我们建议，未来研究和检查光滤光片的生理效应，除了光谱透过率之外，还量化滤光片的视觉和非视觉效应，这最终将有助于了解不同滤光片如何影响生理学的机制。我们强烈反对在不考虑它们对视网膜刺激的影响的情况下，比较不同滤光片对例如睡眠或昼夜节律反应的下游影响。
