On Sleep Indicators

John Gruber linked to this article on Flood Lite today:

In July 2002, Apple filed a patent for a “Breathing Status LED Indicator” (No. US 6,658,577 B2). They described it as a “blinking effect of the sleep-mode indicator in accordance with the present invention mimics the rhythm of breathing which is psychologically appealing.”

The average respiratory rate for adults is 12-20 breaths per minute, which is the rate that the sleep-indicator light fades in and out on most Apple laptops. Older models such as the Macintosh PowerBook, however, use a blinking LED indicator, with discrete pulses in one-second intervals.

Apple’s attention to detail is amazing, but to this day it perplexes me that the iMac doesn’t have a sleep indicator. The unibody MacBook Pros’ sleep LEDs are hidden in the aluminum; why not use a similar design on the desktop?