updated 06:50 pm EDT, Fri August 27, 2010
Dell misses mark, times LSD to strenuous activity
In a nod to Apple's attention to detail and human engineering, Flood Light describes how Apple got its sleep status indicator right, while Dell got it wrong. A July 2002 patent for a Breathing Status LED Indicator describes how the blink rate of a sleep status LED would be timed to a slow breathing rhythm. The blink rate of current Mac notebooks falls within the average respiratory rate of an adult -- between 12-20 breaths per minute. For example, the blink rate of the MacBook Pro 15in late 2008 is exactly 12 cycles per minute.
Dell laptops have a sleep indicator as well, but fail to get the timing to a calm breathing rate. Dell instead uses 40 cycles per minute, which is close to the average respiratory rate of an adult during strenuous exercise. Dell's sleep light is more indicative of a race, missing the human engineering mark that Apple precisely hits.