Japanese lens manufacturer Tokai Optical has launched a newly developed No Reflection Coating (NRC) in response to increased reliance on screen-based communications.
“With an increase in time spent indoors and an increase in frequency using digital devices, including video streaming services, remote work and web meetings, how you look through imaging technology is becoming more important,” the company said.
In response, Tokai Optical has designed NRC with an emphasis on two factors: reflectance and relative luminous efficacy.
“The higher the reflectance, the higher the effect of reducing extraneous light. The second factor, daylight relative luminous efficacy, is the value of light representing the degree of brightness perceivable to human eyes by wavelength in relation to light energy. Even if the amount of light is the same, the brightness of light human eyes feel is different depending on the wavelength,” the company said.
“In this graph, the vertical axis is reflectance, and the horizontal axis is the wavelength range. NRC has achieved a luminous efficacy reflectance of approximately 0.19%, which is approximately one-fourth of conventional multi-coatings.”
Tokai Optical said NRC keeps reflectance low and, at the same time, further reduces reflections more than conventional multi-coatings by turning the reflected colours into bluish purple, considering the daylight relative luminous efficacy curve.
“A curve shows light in a relative value at a wavelength of 555 nm, at which people feel light brightest, as the reference value is called a relative luminous efficacy curve. As this graph shows, the same energy of light looks different to human eyes between a wavelength of 555 nm and other wavelengths. This means that when the amount of light is the same, the wavelength of green is the highest in the intensity of light people feel, and the wavelength of purple or red is the lowest,” the lens manufacturer explained.
NRC provides the wearer with the lowest reflection and clearest vision and offers a premium scratch resistance capability, the company said.
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