Canon says it has developed Blue Spectrum Refractive (BR), a new optical element for use in camera lenses that corrects chromatic aberrations at an extremely high level to achieve superb imaging performance.
The BR optical element, positioned between two glass lens elements to create a BR lens, will makes its debut in the new EF 35 mm f/1.4L II USM wide-angle fixed-focal-length lens, which is scheduled to go on sale in October.
The new optical element offers characteristics that significantly refract blue light, which lies within the short-wavelength range, to achieve impressive levels of chromatic aberration correction for outstanding imaging performance, the company explains.
Natural light, or white light, comprises a spectrum of wavelengths, or colours, each of which realizes a unique refractive index when passing through a lens. As all colours do not converge on the same point, this disparity causes chromatic aberrations, or colour fringing, to occur in an image.
With the development of the BR optical element, which offers unique light-dispersion characteristics that significantly refract blue light – a wavelength that had been particularly difficult to converge to a specific focal point – Canon suggests it is able to develop lenses that result in outstanding imaging performance by correcting chromatic aberrations at an exceptionally high level.