|
Your monthly guide to staff training outside the box
Eyes / Lenses / Fitting Lenses / Free-Form / Frames / Sunwear / Patient Solutions / In-office / Standards
PATIENT SOLUTIONS — Color Vision
VISIBLE LIGHT AND COLOR
By Darryl Meister
The spectrum of electromagnetic radiation includes cosmic rays at one end and radio waves at the other. We think of light as the visible portion of this electromagnetic spectrum. This means that the radiation can stimulate the photoreceptors within the retina of the eye, creating a visual sensation. This region consists of electromagnetic radiation whose waves range from 380 to 760 nanometers (nm)—or one billionth of a meter—in length. This is only 0.000380 to 0.000760 millimeters! The range of radiation visible to the human eye is referred to as the visible spectrum, ranging from violet at one end of the spectrum to red at the other, and represents a small fraction of the total electromagnetic spectrum.
See Plus »
|
|
|
Why Does Color Deficiency Matter?
|
By Robert S. Christensen, OD
Those without color deficiency (myself included) may not realize all the things you rely on color recognition for. When you're driving, not only the stoplights, but the signs on the road are partly recognizable because of their color, and if you see a sign with letters and background that happen to have colors you don't have the ability to see, you may not see the words at all. In a less serious, but no less inconveniencing sense, the ability to coordinate your clothes and put yourself together also can be affected.
See Plus »
|
|
Color Vision Deficiency (CVD)
|
There are more than 13 million people in the U.S. with color vision deficiency (CVD). There are two ways that a
person becomes color deficient. The majority of CVD individuals are born with it, i.e., it's hereditary. The other is by disease or from toxic substances that can create a color vision deficiency problem.
See Plus »
|
|
Let Me Recommend...
|
By Mark Mattison-Shupnick
Color Vision Deficiency, A Concise Tutorial for
Optometry and Ophthalmology from Richmond Products
This booklet is an invaluable reference for the optician that wants a better understanding of color vision and more importantly, color deficiency. This booklet starts with: "Many times each day we use our color vision ability to discern and evaluate objects, signs, situations and other phenomena, often concerning matters of safety, work or pleasure, and observation in general. Use of color is considerably more prevalent in today's information-oriented environment with the advent of color computer displays and printers, for example. With age, color vision often deteriorates at a faster rate than visual acuity."
See Plus »
|
|
Our Eyes
Our eyes are stimulated by the visual spectrum—electromagnetic radiation from 400 nm to 700 nm—and contain different color sensitive retinal receptors. There are three polychromatic receptors called cones, which are stimulated to generate an electric signal based on certain wavelengths and intensities of light. These three types of cones define our vision as "trichromatic." The interaction of the electric signals that these cones send to the brain through the optic nerve is necessary to produce the ability to perceive color. The three types of cones are Short (420 to 440 nm), Medium (530 to 540 nm) and Long (560 to 580 nm). The increased ability to perceive more colors from this overlap is advantageous. Any wavelength of light from 420 nm to 660 nm will produce a unique set of responses that combines all three cone types.
See Plus »
|
SMART SUNGLASSES: FIVE-POINT FILTRATION TECHNOLOGY
Today's high-tech sunglasses integrate many technologies to deliver the highest level of protection and performance to the wearer. Specifically-tailored filter recipes (colors with selective absorption of specific wavelengths) are available for just about every activity. One or more of the following high-performance components are found in today's smart sunglasses.
Chromatic contrast control filters light of different wavelengths, designed to enhance contrast by modifying color discrimination. For example, the target color of a skeet or clay pigeon is enhanced, while the background sky colors are reduced or suppressed in the Pilla Sports lens.
Glare control filters both overall and selective brightness, and may include a reduction or enhancement of reflected light. For example, the general-use sunglass wearer can benefit from the safety and comfort aspects of polarized lenses blocking reflected light, whereas a competitive golfer utilizes and requires subtle cues—gleaned from reflections off the grass blades on the greens—to best evaluate ground contours during putting (Nike Golf).
Dynamic brightness control creates lenses to rapidly adjust to changes in overall outdoor brightness. The newer photochromic lenses excel here, as they are engineered to not only work effectively behind the windshield of a car, but also can include Chromatic Contrast Control as well (Julbo Falcon lenses, Younger Optics Drivewear lenses).
Effective solar protection is critical. This is achieved best when a lens blocks everything that we know to be harmful: UVB, UVA, High-Energy Visible Light (HEVL, also known as high-energy blue light), and may include a portion of the infrared, or heat spectrum.
Authentic, in prescription is designed for every optical office. The special filtration recipe of smart sunglasses is now available to the prescription wearer as well. Many sunglass companies, such as Rudy Project, Oakley, Serengeti, Maui Jim, Julbo, 7eye, etc., offer authentic prescription programs to ensure everyone—nonprescription and prescription wearers—can enjoy identical benefits of their solar protection and color enhancement technology.
For the life of the Rx is a promise. The benefits of authentic lenses will last the life of the prescription. This is accomplished by confining the proprietary recipe of color filtration, photochromism or polarization within 0.9 mm of the front of the semi-finished lens.
—Barry Santini
See Plus ยป
|
|
|
|
