Lighting for the Aging Eye
As we age, natural physical changes of the human eye diminish our visual abilities
including our ability to read.
The cornea becomes more opaque, the lens absorbs more light, and the pupil
diameter decreases, resulting in a reduction in retinal illuminance. Increased fat
deposits in the cornea and lens lead to an increase in light scattering inside the eye, making it more difficult for the eye to recognize the visual images. The lens yellows and absorbs a higher amount of blue wavelengths. Last but not least, weaker ciliary muscles and an increased rigidity and hardening of the lens reduce our ability to focus and to adjust to different light levels easily.
Holtkötter has initiated and supported research at the University of Colorado at
Boulder to study and develop the scientific basis of lighting for the aging eye and to research how good lighting can mitigate the effects of the natural physical changes that we all are subjected to as time passes. Some of the results of this study are being incorporated into this series of table, chair-side and floor reading lamps.
The reduction in retinal illuminance requires a light level of more than 100 footcandles for optimal reading performance. The 75-Watt or 100-Watt Halogen light bulb by Osram, as well as the shape and construction of the inside of the reflector, allow for a light level in excess of 100 footcandles. A matte glass diffuser and a reflector that focuses the light only on the reading material will reduce glare and scattering.
Full range dimming controls allow for personal optimal light levels which will minimize the need for the eye to adjust regardless of the different light intensities in the room. The majority of the Holtkoetter reading and task lamps also have moveable reflectors and infinite arm positions so that the light is utilized in the most effective manner.