Navigation Links
Barrow scientists discover ways to optimize light sources for vision

(Phoenix, AZ Nov. 15, 2012) -- Vision researchers at Barrow Neurological Institute have made a groundbreaking discovery into the optimization of light sources to human vision. By tuning lighting devices to work more efficiently with the human brain the researchers believe billions of dollars in energy costs could be saved.

The research was conducted by Stephen Macknik, PhD, of Barrow's Laboratory of Behavioral Neurophysiology, and Susana Martinez-Conde, PhD, of Barrow's Laboratory of Visual Neuroscience. The study is published Proceedings of the National Academy of Sciences. The paper, titled "Optimizing the temporal dynamics of light to human perception," is believed to be the first attempt to tune light-emitting devices to the optimal temporal dynamics of the human visual system.

The discovery concerns the way humans perceive temporal modulations of light. For example, most light-emitting devices, such as light bulbs, video monitors and televisions, flicker. Faster flicker rates result in reduced perception of flicker, which is more comfortable to viewers. In studying this phenomenon in the brain, the researchers discovered that there is a range of flicker dynamics of light that optimizes the perceived brightness of the light without increasing power.

"We found a temporal sweet spot in visual perception that can be exploited to obtain significant savings by redesigning light emitting devices to flicker with optimal dynamics to activate visual system neurons in the human brain," says Dr. Macknik.

The researchers estimate that if every light-emitting device in the U.S. from light bulbs to cell phones operated at optimal efficiency for the human visual system, it could result in billions of dollars of savings in electricity and power.

To come to their conclusion, the researchers conducted experiments into two contradictory theories of temporal visual perception, or how bright a light appears. Bloch's Law states that the perceived contrast of a visual stimulus increases with its duration, but eventually plateaus at approximately 100 milliseconds. For example, a 5-millisecond flash will appear half as bright as a 10-millisecond flash, but a 200-millisecond flash will be just as bright as one of 400 milliseconds. The Broca-Sulzer Effect, on the other hand, states that perceived contrast increases with duration initially, but then peaks and falls again.

The researchers discovered that the discrepancy between Bloch's Law and the Broca-Sulzer Effect is caused by an intrinsic bias among experiment subjects, leading to dramatically skewed data. By improving their experimental design to overcome this bias, something that has never been before reported or intentionally controlled for, the results demonstrated that temporal vision actually follows the Broca-Sulzer Effect.

"Researchers have been studying temporal vision for more than 125 years, but because ours is the first experiment of its kind to control for all known forms of criteria, it is the first to accurately measure the role of temporal dynamics in brightness perception," says Dr. Macknik. "Thus, the power savings are ripe for the picking because we can adjust our lighting to flicker to take advantage of this peak in perception."


Contact: Lynne Reaves
St. Joseph's Hospital and Medical Center

Related biology news :

1. WSU scientists find new way for antibiotic resistance to spread
2. NIH awards Penn scientists $10 million over 5 years for innovative research on single cells
3. Scientists question the designation of some emerging diseases
4. Watching the developing brain, scientists glean clues on neurological disorder
5. Scientists take objective look at terms least toxic pesticides applied as last resort
6. Scientists unravel the mystery of marine methane oxidation
7. Scientists discover new method of gene identification
8. Weber State Scientists discover possible building blocks of ancient genetic systems
9. Space research institute awards postdoctoral fellowships to 4 scientists
10. Space research institute awards postdoctoral fellowships to four scientists
11. 3,000 insect scientists coming to Knoxville next week
Post Your Comments:
(Date:11/12/2015)... 11, 2015   Growing need for low-cost, ... has been paving the way for use of ... discrete analytes in clinical, agricultural, environmental, food and ... used in medical applications, however, their adoption is ... to continuous emphasis on improving product quality and ...
(Date:11/9/2015)... JOSE, Calif. , Nov. 9, 2015  Synaptics ... human interface solutions, today announced broader entry into the ... vehicle-specific solutions that match the pace of consumer electronics ... and biometric sensors are ideal for the automotive industry ... vehicle. Europe , ...
(Date:10/29/2015)... RESTON, Va. , Oct. 29, 2015 ... announced today that it has released a new version ... Daon customers in North America ... gains. IdentityX v4.0 also includes a FIDO UAF ... customers are already preparing to activate FIDO features. These ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... Nov. 24, 2015 Cepheid (NASDAQ: CPHD ... at the following conference, and invited investors to participate ...      Tuesday, December 1, 2015 at 11.00 a.m. ...      Tuesday, December 1, 2015 at 11.00 a.m. ... New York, NY      Tuesday, December ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... metabolism. But unless it is bound to proteins, copper is also toxic to ... researchers at Worcester Polytechnic Institute (WPI) will conduct a systematic study of copper ...
(Date:11/24/2015)... 2015  Clintrax Global, Inc., a worldwide provider of clinical research ... announced that the company has set a new quarterly earnings record ... quarter growth posted for Q3 of 2014 to Q3 of 2015. ... Mexico , with the establishment of an Asia-Pacific ... United Kingdom and Mexico ...
(Date:11/24/2015)... ... November 24, 2015 , ... The Academy of Model ... Group (SIG), MultiGP, also known as Multirotor Grand Prix, to represent the First–Person View ... years. Many AMA members have embraced this type of racing and several new model ...
Breaking Biology Technology: