Period Costs. Period costs are expenses that are easier to attribute to times and accounting periods than actual production processes or finished goods. Typically, managerial accountant want to classify expenses in categories that can improve operations. Manufactures tend to focus on functional classifications.
The amber color of these impact-resistant polycarbonate lenses block short-wavelength blue light and 100% of ultraviolet (UV) light, thus providing additional protection against cataract formation and the development of macular degeneration, while increasing contrast on both sunny and bright hazy days.
Do they block so called âcomputer blue light or should I invest in clip-on lenses that do block this portion of the light spectrum? Written answer: Although polycarbonate lenses will absorb almost all UV light without the addition of a coating, it will not absorb blue light, so you will need a tint or clip-on lens.