![]() ![]() In classical thermodynamics it was known that matter emitted radiation the frequency of which depended on the temperature. Itt could not explain the frequencies the spectrum of radiation coming from matter, and quantum mechanics was discovered because of this. Thermodynamics is the classical physics regime. The question of what causes an object to absorb some wavelengths and reflect or scatter other wavelengths requires a much more complicated answer, because it depends on the atomic, molecular, and structural properties of the object's composition. Our eyes have receptors for three different ranges of visible wavelengths, and the specific color we perceive at any point in an image depends primarily on the relative intensity of light in each of those three ranges. If wavelengths in the long and short range of the visible spectrum are absorbed but those in the middle range are reflected, the reflected light reaches our eyes and is perceived as green - and so on. If all of the visible wavelengths of the white light are absorbed, our eyes will see no light at all, and our brains interpret that as a black color. When white light illuminates an object, the object will absorb some wavelengths and reflect/scatter other wavelengths. White light - e.g., sunlight - contains all wavelengths. In both the light and the dark there were some very strongly fluorescent fibers mixed in.The question suggests a slight misunderstanding about color:īlack color absorbs light better than any other.Ĭolor does not cause absorption. With blue light excitation the bulk of the dark lint seemed to not produce much fluorescence, while there was a weak general fluorescence from the light lint. (Anyone from the Nobel committee paying attention?) Under ultraviolet excitation both fluoresced blue-white, and the light lint fluoresced much more intensely than the dark. As you can see in the white-light image below, the load of light-colored clothes produced light lint while the load of darks produced dark lint. The first set of images below shows the collected lint as a whole, against a white posterboard background. It is almost hard to believe that they are images of the same sample. So it should come as no surprise that I found a blue-white fluorescence under UV light.īut what was really striking was the difference in fluorescence between the dark and light lint under UV and blue light excitation. And what is dryer lint but a large collection of these fibers. Anyone who has been in a place using black lights has probably noticed fibers fluorescing blue-white. These are designed to absorb ultraviolet light and emit in the blue portion of the spectrum. Laundry detergents commonly include fluorescent brighteners to make ‘whiter whites, brighter brights’. Startling results – It was no surprise that there was fluorescence. ![]() So I ran the two loads and explored the resulting specimens under white light, excitation by longwave ultraviolet light (predominantly 365nm), and excitation by blue light (~440-460nm). What if I suppressed my natural urges and separated the lights and the darks and washed them separately? Would I see a difference in the lint captured on the dryer filter? And by ‘difference’ I of course mean ‘fluorescence difference’. Inspiration – At the last moment it occurred to me that this was an opportunity to run an experiment. I had done this plenty of times before and nothing particularly bad (or pink) had come of it yet. My normal (apparently male) predilection is to just dump all the clothes in together since we run a cold water wash cycle. Your intrepid spectral explorer, NIGHTSEA founder Charles Mazelīackground – Recently my wife was out of town long enough for me to have to take sole responsibility for the accumulated laundry. A dispatch from the front lines of fluorescence
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |