- Organic compound
- low running cost
- low power consumption
- ideal for subtle back lighting
- can form high impact images
- can appear animated
- water proof
- can be sandwiched together or produced as wire or strips.
- has colour limitations
- high cost to initially set up
- low tech compared to LCD's
- background effects only
- used in electronic books
- a pixel is a tiny pit containing a number of black and white beads which are charged positively and negativel. each pit has a transparent electrode on top and two at its base.
- altering the charge on the base electrodes makes either the white or black beadl leap to the top of the pit forming either a blank or black spot on the large display.
- electronic paper was developed to overcome limitations of computer monitors
- piezoelectric crystal converts mechanical stress or vibration into electrical vibrations.
- expands and contracts when an electric current is applied.
- used in musical greetings cards
Thermochromic Liquid Crystals
- used in forehead thermometres, battery test panels and special printing effects.
- a layer of conductive ink is screen printed on to the reverse of the thermometer ***** - this makes contact with the forehead. ontop of the conductive bar is a layer of normal ink that conveys the temperature gauge colour bar. then there is a thermochromic which is black in colour when cool.
- by pressing the bar on the forehead the temperature generated turns the thermochromic ink translucent - revealing the temperature gauge colour bars.
- absorbs energy or 'charge' in normal daytime conditions and are capable of storing that energy for some time, then releasing it slowly in the form of light
- non radioactive materials
- can be manufactured into paints or inks to make safety signage and watch faces that can be seen in complete darkness.
Radio Frequency Identification
- RFID is a method of identification that uses tags stuck on to a product to store data that can be retrived by a reader.
- RFID technology is based on the transmission and reception of radio frequency (RF) signals between a transmiter and a responder/tag attatched to a product.
This method is often used to track products from the manufacturer to the retailer.
It also has applications in libraries, a tag is used on a book to identify the book and lender and isuseful as a security measure to stop books from being stolen.
RFIDs can also be used in livestock management.