Radiant energy – Invisible radiant energy responsive electric signalling – Ultraviolet light responsive means
Reexamination Certificate
1999-06-24
2002-02-19
Hannaher, Constantine (Department: 2878)
Radiant energy
Invisible radiant energy responsive electric signalling
Ultraviolet light responsive means
Reexamination Certificate
active
06348694
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to exposure of skin to harmful radiation, and more particularly, to methods and apparatus for determining both an ability of the skin to withstand exposure to the harmful radiation, as well as a safe exposure time of the skin to the harmful radiation.
BACKGROUND OF THE INVENTION
Radiation emanated by the sun, commonly referred to as “sunlight,” is composed of many different wavelengths of electromagnetic radiation. The spectrum of radiation constituting sunlight may be categorized generally into infrared energy wavelengths, visible light wavelengths, and ultraviolet light wavelengths. Infrared energy typically includes wavelengths above approximately 760 nanometers. Visible light typically includes wavelengths in a range of from approximately 400 nanometers to 760 nanometers. Ultraviolet light typically includes wavelengths below approximately 400 nanometers.
Over the years, scientists, medical researchers, and the like have discovered that humans are susceptible to a variety of internal and external bodily damage from exposure to various wavelength ranges of radiation. In particular, researchers have discovered that humans are among the living beings most vulnerable to a number of ailments associated with exposure to ultraviolet radiation. Excessive exposure to ultraviolet radiation has been linked to skin cancer, cataracts in human eyes, sunburn, skin wrinkling, and other external and internal bodily damage. While, in the past, the earth's ozone layer acted as a natural filter for ultraviolet radiation emanated by the sun, thereby limiting potentially harmful ultraviolet rays from reaching the earth's surface, a decrease in the earth's ozone layer in recent years has resulted in an increased exposure of the earth's surface to ultraviolet radiation.
The potentially harmful effects of over-exposure to various harmful radiation, such as ultraviolet radiation, pose a particularly insidious threat to humans. For example, in general, long-term damage caused by ultraviolet radiation may begin in early years, with sunburns that occur during childhood and the teenage years. Notwithstanding early exposure, however, the cumulative effects of exposure to ultraviolet radiation generally do not begin to manifest themselves until mid-life, between the ages of 40 to 60, when it is often too late to rectify such damage and prevent further damage.
Many medical professionals believe that skin cancer has become one of the most widespread forms of cancer today, as a result of the decrease in the earth's ozone layer and early over-exposure to ultraviolet radiation. It is currently estimated that over one million people in the United States develop different types of skin cancer every year. Although skin cancer is generally considered as one of the mildest forms of cancer, approximately 7% of those people afflicted with skin cancer die as a result. In some areas of the world, for example, the United Kingdom, skin cancer is currently the second most common form of cancer.
Wavelength ranges of ultraviolet radiation which are potentially harmful, as well as threshold limits of exposure intensity associated with such wavelength ranges, have been studied by the American Conference of Governmental Industrial Hygienists (ACGIH). The ACGIH, as well as other health related organizations world-wide, have determined that the most harmful ultraviolet wavelengths are in a range from approximately 200 nanometers to 320 nanometers. Threshold limit values for exposure to these ultraviolet wavelengths have been set forth in the publication “Documentation of the Threshold Limit Values and Biological Exposures Indices,” American Conference of Governmental Industrial Hygienists, Pub. No. 0206, ISBN: 0-936712-96-1, pp. 671-674. Additionally, the Diffey Erythema Sensitivity Spectrum, which was developed to describe the relative sensitivities of human skin in general to particular ultraviolet wavelengths, has been accepted throughout the world as a generic indicator of human susceptibility to harm from ultraviolet radiation.
As discussed above, due to the filtering function of the earth's ozone layer, the intensity of ultraviolet radiation emanated by the sun and reaching the earth's surface is not uniform throughout the ultraviolet wavelength spectrum. By considering both the spectrum of ultraviolet radiation that actually reaches the earth's surface through the ozone layer, in combination with the Diffey Erythema Sensitivity Spectrum of relative human sensitivity to ultraviolet wavelengths, an “effective ultraviolet spectrum” can be constructed for humans on the earth's surface. Such an effective ultraviolet spectrum reveals that the particular ultraviolet wavelengths most harmful to humans are in a narrow range of from approximately 300 nanometers to 320 nanometers. This ultraviolet wavelength range is commonly referred to as UV-B. It should be appreciated, however, that other wavelength ranges, including other ultraviolet ranges such as UV-A (from approximately 320 nanometers to approximately 400 nanometers), may be potentially harmful to humans.
To reduce ultraviolet radiation exposure, it is common to apply a sunscreen, or an ultraviolet radiation blocking cream, to the skin. In general, while some types of sunscreen are designed to reflect ultraviolet radiation to some extent, other more common types of sunscreen contain ultraviolet radiation absorbers, which absorb or “block” part or most of the harmful ultraviolet radiation to prevent it from reaching the skin, depending upon the amount of the absorbers present in the sunscreen. Many sunscreens, however, whether reflecting or absorbing, do not completely block ultraviolet radiation and, in particular, allow some of the harmful UV-B range of ultraviolet wavelengths to reach the skin. Additionally, while most sunscreens are labeled with a generic “sun protective factor,” or SPF, it is often difficult to ascertain the actual effectiveness of the sunscreen, as well as the actual total exposure level to harmful ultraviolet radiation, with respect to a particular individual.
Several medical professionals have suggested that the probability of an individual to develop skin cancer, or other ailments associated with exposure to ultraviolet radiation, likely depends on several “personal” factors, in addition to the level of harmful ultraviolet radiation reaching the earth's surface to which the individual is exposed. Examples of other factors that likely affect an individual's propensity to suffer harm from over-exposure to ultraviolet radiation include the total exposure time to ultraviolet radiation, any personal or family history of skin-related and/or cancer-related ailments, and an individual's skin type or “darkness.” In particular, the risk of developing skin cancer or other ultraviolet radiation related damage may be higher, for example, for more fairly-skinned people who may freckle or burn easily, or those with more lightly colored hair.
Another potentially significant factor that affects an individual's propensity to suffer harm from over-exposure to ultraviolet radiation relates to the actual effectiveness of any sunscreen applied to the particular individual's skin, given other personal characteristics of the individual, such as skin darkness. The generic sun protection factor (SPF) with which most sunscreens are typically labeled merely indicates a multiplication factor of protection against ultraviolet radiation, based on any “natural” protection afforded by human skin itself. For example, an SPF of 15 suggests protection from ultraviolet radiation on the order of approximately 15 times that of the natural protection afforded by human skin.
However, there may be several instances in which the actual SPF of a sunscreen applied to a region of skin may be different than a labeled SPF of the sunscreen. For example, one factor related to the effectiveness of sunscreen applied to an individual's skin is how thickly the sunscreen is applied to
Gershtein Elliot
Gershteyn Mikhail
Schechter Alexander
Hannaher Constantine
Lee Shun
LandOfFree
Method and apparatus for determining an ability of skin to... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for determining an ability of skin to..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for determining an ability of skin to... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2985506