All about Flexible Macroelectronics

17 January 2009

This is the forth post of the Macroelectronics.org OLEDs series. Stay tuned.

AMOLED, or active matrix OLED, is composed of an anode, a cathode, an organic layer, and a thin film transistor (TFT) matrix. Each pixel of the OLED is integrated onto a TFT array. TFT array controls the amount of current flows on each pixel which determines the brightness of generated light.

Instead of having external circuit to turn on/off the cathode and anode stripes that activate pixels in passive matrix configuration, AMOLED allows the current to flow through all of the OLED pixels while having TFTs controls how much current will each pixel gets. This is one of the advantages of AMOLED over PMOLED because TFT arrays need less power than external circuit. In addition, AMOLED’s pixel turns on and off at an incredibly rapid rate making it ideals for motion pictures. Though, AMOLED’s main disadvantage is its expensive manufacturing cost due to the intricacy of the active matrix structure that requires complex processes to fabricate.

Many leading display companies today such as Samsung, LG, Sony, Universal Display, Nokia and Kodak see a potential of and working on developing AMOLED displays. AMOLED now has become a promising technology for large display and portable display products.

(via universal display, howstuffworks, wikipedia, and oled-display ; image credit: howstuffworks and oled-display)

Labels: OLED

Posted at 10:55 by Ed Dechaumphai| Editor: Teng Li

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Applications of RFIDs (Part 1 of 3)

16 January 2009

RFIDs, as mentioned before, come in several different forms, each with its own advantages and disadvantages. Passive RFIDs do not have their own power supplies, but are limited to short range communications with the reader; Active RFIDs have longer ranges, but are more susceptible to interference.

Currently, in everyday use, we use RFIDs for theft prevention at stores. However, several companies have come up with several novel ideas to make lives easier.

Such a company is Metro Group. Innovating from the warehouse to one's home, their concept of the RFID is prevalent throughout everyday life from when one reaches for the milk in the refrigerator to sorting clothes for the laundry machine.

Metro Group is one of several companies making the RFIDs that are placed in warehouses to account for inventory. They also have concept designs for refrigerators that tell the owner if he or she is out of milk; laundry machines that can detect when you've mixed in a red sock with your white laundry; mirrors that can take a snapshot of your physique so that you can try on the clothes that you picked out without actually having to wear them; and personal pads that you can carry around in a store, which document which items you are about to purchase. The last allows the shopper to pass through a scanner, with credit card in hand and, with the items already listed, payment is all but a swipe away.

All of these items mentioned, from the red sock to the milk to the new outfit, are all fitted with RFIDs, which originate from the warehouse with the original shipments. These RFIDs are integrated into our everyday lives so that you do not have to worry about minute things of everyday life.

(via Metro Group; Photo Credit: Space is Lost)

Labels: RFIDs

Posted at 20:30 by J| Editor: Teng Li

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OLEDs: types and applications - PMOLED

05 January 2009

This is the third post of the Macroelectronics.org OLEDs series. Stay tuned.

The Passive-Matrix OLED or PMOLED is the first OLED to be commercialized. PMOLED is composed of anode strips, cathode strips, an organic active layer, and a substrate. Passive matrix is the configuration in which anode and cathode strips are arranged perpendicularly having an organic active layer in between. The intersections between anode and cathode strips are pixels. Light is generated when current passes through the selected anode and cathode strips. Therefore, turning on/off the current that goes through strips determined which pixels will be displayed and an image is created. Even though PMOLED is easy to fabricate and manufacture, the external circuit that controls current source is relatively expensive. Comparing to other OLED types, PMOLED is less efficient mostly due power loss from diodes and the strips. Though, this type of OLED still consumes less power than LCD display. Therefore, PMOLED is the most power efficient in and best used for small displays ranging from 2” to 3”. Currently they are used in cell phones, music players, GPS, and portable displays.