Night Vision Goggles
Night glasses are telescopes or binoculars with a large diameter objective. Large lenses can gather and concentrate light, thus intensifying light with purely optical means and enabling the user to see better in the dark than with the naked eye alone. Often night glasses also have a fairly large exit pupil of 7 mm or more to let all gathered light into the user's eye. However, many people can't take advantage of this because of the limited dilation of the human pupil. To overcome this, soldiers were sometimes issued atropine eye drops to dilate pupils. Before the introduction of image intensifiers, night glasses were the only method of night vision, and thus were widely utilized, especially at sea. Second World War era night glasses usually had a lens diameter of 56 mm or more with magnification of seven or eight. Major drawbacks of night glasses are their large size and weight.
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Famous quotes containing the words night and/or vision:
“Let me have wisdom, Beauty, wisdom and passion,
Bread to the soul, rain when the summers parch.
Give me but these, and though the darkness close
Even the night will blossom as the rose.”
—John Masefield (1878–1967)
“I want you to consider this distinction as you go forward in life. Being male is not enough; being a man is a right to be earned and an honor to be cherished. I cannot tell you how to earn that right or deserve that honor. . . but I can tell you that the formation of your manhood must be a conscious act governed by the highest vision of the man you want to be.”
—Kent Nerburn (20th century)