By Julie Steenhuysen

CHICAGO (Reuters) – U.S. researchers said on Thursday they have found a way to make large-scale flexible display screens that can be stretched to fit the contours of a bus yet are transparent enough so riders can see out windows.

The thin, light screens might be used to make brake light indicators that follow the contours of a car, or health monitors or imaging devices that wrap around a patient like a blanket, said John Rogers of the University of Illinois at Urbana-Champaign, whose study appears in the journal Science.

He said the large display screens combine the scale and durability of light-emitting diodes, or LED technology, used to make flat, lighted billboards, with the flexibility of screens made using organic — carbon-containing — materials.

“If you look at these giant billboard displays along the road side, those are made out of inorganic light emitting diodes (LEDs). Our feeling is those systems are quite impressive,” Rogers said in a telephone interview.

“The question became is it possible to take that technology and use it in a non-billboard format.”

Rogers said current technology using inorganic materials produces chunky individual LED lights that need to be arranged piecemeal with a robotic arm. Screens made using organic materials can be sprayed or painted onto a film surface, but they are not as bright or durable, he said.

To solve this challenge, researchers built their LEDs on a thin layer of film later dissolved by a chemical and then affixed tiny plastic tabs on two corners to ensure the LEDs did not wash away in the chemical bath.

The team used a special stamping technology to deposit and assemble the inorganic LEDs onto glass, plastic or rubber surfaces. The system works much like a rubber stamp and ink pad, using the LEDs as ink.

“The new approach can lift large numbers of small, thin LEDs from the wafer in one step, and then print them onto a substrate in another step,” Rogers said.

The LEDs can be interconnected and wired with a conventional process used to wire computer chips, he added. And because LEDs can be placed far apart and still provide enough light, the panels and displays can be nearly transparent.

“We can put them on a strip of plastic and make brake lights,” said Rogers, who noted that the project was initially funded in part by Ford Motor Co, which was looking for a way to make brake lights that can follow the contour of a car.

The National Science Foundation and the U.S. Department of Energy also funded the project.

(Editing by Maggie Fox and Paul Simao)

DEMAREST — It’s gotten easier to spot Demarest crossing guards as they enter intersections.

By Michelle Sartor
News Editor | Jan. 15
Source: nvsuburbanite.com

DEMAREST — It’s gotten easier to spot Demarest crossing guards as they enter intersections.

The guards were issued new LED, light-emitting diode, stop sign paddles Jan. 8 that are meant to increase safety for both the guards and the children they cross every school day. Each sign cost about $165.

Police Chief James Powderley brought the signs to the Borough. He first saw them at the International Association of Chiefs of Police conference in the fall and thought they would be extremely beneficial.

When the crossing guards raise the paddles above their waist, “STOP” is lit up with white LED lights and flashing red lights appear above and below the word. When the guards put the signs down, all the lights turn off.

Powderley said the lights turn on and off automatically with a ball switch located inside the signs. When the signs are lifted, the ball travels to the bottom, initiating the lights. The paddles also contain an on/off switch and have internal rechargeable batteries.

The LEDs, which emit low watts and can run on a single charge for days, have a lifetime warranty. According to Powderley, “At most we’d have to change the rechargeable batteries down the road.”

With the LED lights, Powderley said the new paddles are “visible for well over a mile.” He said the lighted signs are especially helpful in inclement weather.

THE NUMBERS

• Demarest has 11 crossing guard posts to cover.

• The Borough has 14 crossing guards and is in the process of hiring another.

• The LED stop sign paddles cost approximately $1,600.

• The magnetic car signs cost about $800.

• The collapsible cones will cost approximately $1,100.

• The last reported incident of a crossing guard being struck by a vehicle was in 2001.
Even without the LED lights, the signs are better than what crossing guards had previously. The new paddles have reflective tape in addition to the lights, which makes them more reflective than the old stop signs, which just contained “STOP” in white letters on a red background.

The newly issued signs are also smaller, lighter weight and have a comfortable handle, which Powderley said makes them easier for crossing guards to use.

So far, feedback has been positive. “In the morning when it’s still cloudy and dark you can see the signs from a farther distance,” said Joe Woska, a crossing guard at the intersection of County Road and Hardenburgh Avenue. “It’s much safer.”

Diane Marello, who crosses students on Knickerbocker Road and Park Street, thinks the paddles are a good addition. “They’re great for visibility,” she said. “It brings attention that there’s a crossing guard in the street. It’s safer for the children and us.”

Stop-Lite manufactures the paddles, which sell for more than $165 apiece. Global Procurement Services, based in Chicago, is the parent company.

The paddles are just one component of a new safety package for Demarest’s crossing guards, which is costing the Borough approximately $3,500. In addition to the new signs, the guards have been issued magnetic signs for their cars and new collapsible cones that say “Demarest School Crossing Guard.” The color for both items is safety green, a custom color that is meant to stand out.

Powderley said the magnetic car signs are helpful to the community. “All crossing guards are members of the Police Department. We tell the kids each is an official you can go to for help. It helps kids identify who the guards are and their vehicles,” he said. “Also, when the car is on the street, motorists and residents can see a guard is on duty and use more caution.”

The new cones, which have not come in yet, will take the place of rubber cones the Police Department currently has. Powderley said the collapsible cones are lightweight and compact for the crossing guards to transport in their vehicles and store, folding into a “flat, pancake type square.”

They rise into full-sized safety cones so motorists can easily see that a guard is present.

Powderley is proud of this safety initiative. For the past several years he has set aside money to upgrade safety features for the Borough’s crossing guards. Last year they received new multi-season, safety green jackets with reflectors along with matching gloves and hats. The year before, each got badges and whistles with lanyards.

“Crossing guards are one of the top two most dangerous municipal jobs,” Powderley said. “Anything to make the job safer is a benefit.”

While all crossing guards are required to undergo training, accidents do happen. A guard was struck and injured at the intersection of Brookside and Hardenburgh avenues in 2001. Although no other incidents have occurred, Powderley said guards regularly report “close calls.”

These new items are meant to decrease the chances that a crossing guard gets hurt while on the job.

The stop sign paddles are the most interesting aspect of the safety package, and probably the most visible. Powderley said, “I think you’re going to see them all over the state in time.”

E-mail: sartor@northjersey.com or call 201-894-6703