Friday, January 26, 2007

Another Optics Advance

Finally the purpose of eyelashes and squinting explained.
http://www.sciencedaily.com/releases/2007/01/070124175420.htm

3 comments :

Anonymous said...

So that is the purpose of eyelashes and squinting.

Tom Buss

Lief said...

Eyelashes and squinting make you look cool, like Clint Eastwood.

Bop-op said...

Lief is right: the only real purpose of squinting is to look cool.

The Science Daily article is a good example of a misleading explanation. Squinting actually changes the F stop, or the focal ratio of the lens in your eyeball. A longer focal ratio is more forgiving of flaws in the lens, and tends to produce a sharper image, but with less light.

A better explanation is the technology of the SOHO telescope, used for viewing the Sun's corona. It has a device that blocks the Sun, allowing the sensitive camera to record images of the corona and stars behind it. Take a look at the January 15 photos they took of comet McNaught where the comet is so bright that it overwhelms the SOHO camera.

The new "micro shutter" technology allows the camera to block out individual bright stars in an image, in the same way as the SOHO camera blocks out the Sun. This is not even close to "squinting" but is more like holding your hand up in front of your eyes to block out glare so you can see something that is near the glare.