A lady helps her husband install a new computer.
Once it is completed, she tells him to select a password, selecting a word that he'll always remember.
As the computer asks him to enter it, he looks at his wife and with a macho gesture and a wink in his eye, he types: ..... mypenis.
As he hits 'enter', to validate the selection, his wife collapses with laughter and rolls on the floor in hysteria!!
The computer had replied: TOO SHORT- ACCESS DENIED!
Achromatic lensesIn 1758, optician John Dolland, having created achromatic lenses, reported this to the Royal Society. Isaac Newton had described the blurring effect due to chromatic abberation, but could not solve the problem in simple lenses, which was important in the preparation of lenses for telescopes and microscopes. A concave face of a lens of flint glass (which has a greater color dispersion than crown glass) is cemented to a convex face of a crown glass lens. Thus the dispersion properties causing chromatic aberration are removed from both lenses simultaneously. Although Dollond patented the discovery of the achromatic lens in the mid-18th century, it is widely believed that he was not its inventor, but learned about it from lens maker George Bass. |
