Definition
UltraViolet : 100nm to 400nm solar light spectrum

- UV-A : 315~400nm
- UV-B : 280~315nm
- UV-C : 100~280nm
 
Feature
 
UV-A
UV-B
UV-C
Wavelenght [nm]
315 ¢¦ 400
280 ¢¦ 315
100 ¢¦ 280
Operating Temperature
Penetrates the ozone layer
Mostly absorbed by the ozone layer
Almost all absorbed by the ozone layer
Amount reaching the Earth's surface
98% of UV radiation is UV-A
2% of UV radiation is UV-B
Negligible
Effects on human and environment

 • photo aging (winkles)
 • photo-chemical smog

 • vitamin Dgeneration
 • immune suppression
 • skin cancer
 • cataract

 • mutation generation
 • destruction of
   an ecosystem
 • destruction a gene
 
 
 

Factors Affecting the UV intensity
Factor
Influence on UV intensity at the Earth's surface
Position of the sun which varies with time of the year, time of the day and the latitude.
 The higher the sun's position, the higher the UV intensity.
Amount of ozone in the atmosphere.
Ozone absorbs UV radiation. The more abundant the ozone in the atmosphere, the less the amount of UV radiation reaching the Earth's surface.
Clouds and haze.
 UV radiation is both absorbed and scattered by clouds and haze.
Ground reflection.
Most natural surfaces such ac grass, soil and water reflect less than 10% of UV. However, fresh snow strongly reflects (80%) UV. Sand also reflects 10-25% of UV.
Altitude above the sea level.
The higher the altitude, the higher the UV intensity as the depth of the atmosphere and therefore the amount of ozone available to absorb UV radiation is reduced.
 
 
 

Effects of UV Exposure
  • Skin Cancer
According to the National Cancer Institute, more than 600,000 new diagnoses of non-melanoma skin cancer are likely to be reported in the US this year. Other agencies suggest that the estimated number of new cases of non-melanoma is closer to 1 milion. The death rate from non-melanoma cancers is expected to be 1,900. For melanoma, the estimate for 1999 is 44,200 new diagnoses, with 7,300 deaths expected.
 
  • Premature Aging (Photoaging)
  • Cataracts and Other Eye Disorders
  • Immune System Damage
 
  Genicom Co., Ltd. Unit 605, National Nano Fab Center, KAIST, #53-3, Eoeun-dong, Yusung-gu, Daejeon 305-333 Korea
Tel. +82-42-862-3982 ¤Ó Fax. +82-42-862-2982 ¤Ó E-mail: uvsensor@geni-uv.com
UV sensor/UV detector / UV photodiode/ UV index / Ultraviolet