| After piece of paper is fed into printer, what happens? (inkjet) | print head moves across paper to produce an image/character |
| What is an Inkjet printer | a printer in which characters/image are formed by minute jet of ink |
| What are the 4 components in inkjet printer? | 1. a print head
2. ink cartridges
3. a stepper motor and belt
4. paper feed |
| What does a print head consist of in inkjet printer ? | nozzles which spray ink droplets to form character or image |
| How many ink cartridges are there in an inkjet printer | two. One black, one blue, magenta and yellow |
| What does a stepper motor and belt do? | moves the print head across the printer |
| What are the two technologies of inkjet printer? | thermal bubble and piezoelectric |
| How does a thermal bubble printing technology work? | ink vaporize because of heat in the resistors, ink forms tiny bubbles which expands and cause ink to land on paper from print head |
| What is piezoelectric technology in inkjet printer | a crystal located at the back of ink supply for each nozzle is given electric charge, causing it to virate and cause ink to land on paper from printhead |
| How does a printer work | 1. data form file to be print is sent to printer driver, printer driver checks if it's understandable and if printer is able to carry out print job
2. Data sent to printer is stored in printer buffer
3. piece of paper is fed into printer (if no paper, message is sent to computer) and printer head moves across paper to produce character/image
4. after print head passes, paper is advanced to print for next line
5. process if repeated until printer buffer is empty. If empty, printer buffer will sent an interrupt to computer requesting for more data |
| Who checks if data is understandable and printer can carry out job after data form file is sent to printer driver? | printer drivers |
| After printer driver in inkjet printer checks everything's good, where is data stored? | in the printer buffer |
| the process of printing in inkjet printer continues until? | printer buffer is empty |
| What will printer buffer do after it's empty? | printer buffer will sent interrupt to computer requesting for more data |
| What are the advantage of inkjet printer? | best for printing good quality one-off photos (ink cartridges and paper trays are small) |
| What are laser printers? | a printer which makes use of powdered ink and static electricity to print |
| What is the difference in printing styles between inkjet and laser printer? | inkjet printer print line by line while laser printer pint a whole page in one go |
| What kind of printing is suitable for laser printer | large print jobs (test,exams) because it has speed advantages and dont run out of ink halfway |
| How does a laser printer work? | 1. data to be print is sent to printer driver, printer driver checks that data is understandable and printer is available to carry job out
2. data is sent to printer and stored in printer buffer
3. Printer drum in printer is given a positive charge. Laser beam removes charge in certain area, leaving negatively charged areas which match character to be printed
4. the drum is then covered with positively charged toner (powdered ink) which sticks to negative charged areas
5. negatively charged piece of paper rolled over the drum, causing toner to stick on paper, negative charge is then removed
6. paper goes through the fuser,which melts ink onto paper. |
| What happens after data is send to printer and stored in printer buffer in laser printer? | printer drum is given positive charged and laser beam removes charge in blank areas of the paper, leaving negatively charged areas to be print |
| after removing charge in certain areas, leaving negatively charges in paper what happens in laser printer? | drum is covered with positively charged toner (powdered ink) which sticks to negative charged areas |
| What happens after powdered ink is stick to negative charged areas in laser printer | negative charged paper roll over drum, causing toner to stick on paper, negative charge is then removed |
| What happens after toner stick on paper in laser printer? | paper goes through fuser, which melts ink onto paper |
| Why do laser printer have high speed? | because they have large toner cartridges and print trays |
| What is the definition of 3D printer | a printer which makes a physical object from a 3D digital model (used in CAD) |
| what are the two types of manufacturing 3D printer | additive (printed by building layers and layers using powdered resin, powdered metals, ceramic powder) and subtractive (object being carved form stone) manufacturing |
| What are the two types of 3D printers | direct print printer, blinder print printer |
| Describe direct print printer in two points | uses inkjet technology, print head moves side to side like inkjet printer but also up and down to build layers |
| Describe blinder printer in 3 points | print head moves same as direct printing, two substance are sprayed for each layer dry powder and binder to form object, some other also uses UV light to harden liquid |
| How does a 3D printer work? | 1. design is made using CAD software
2. design imported to software which converts design into understandable format for 3D printer
3. 3D printer set up to print
4. the object is build up layer by layer (can take hours)
5. once complete, object is finalized depending on object printed |
| After design is made using CAD software what happens? | design is imported to software which converts design into understandable format |
| What are the 4 uses of 3D printer | 1. make prosthetic limbs
2. make items which allow precise reconstructive surgery
3. light weight plane wings
4. sculptures |
| What is the definition of laser cutter | an output device that is used to cut materials |
| Give 5 examples of materials laser cutter can cut | glass, wood, polymer, crystal, metal |
| What is the difference between 2D laser cutter and 3D laser cutter | 2D laser cutter cuts in x-y direction, 3D laser cutter cuts in x-y-z direction |
| What is the definition of actuators | an electromechanical out put device that is used to control something |
| Where is an actuator used? | used in controlling application |
| How does an actuator work? | when energised, it can operate a plunger or control system |
| What is required to control actuator? | DAC |
| How does actuator link to DAC | computer is connected to actuator and data is sent to it go DAC when being transmitted |
| What is a speaker | an output device that converts electrical impulses into sound |
| How does a speaker work? | sound produced from computer by transmitting digital values through DAC then through amplifier lastly to speaker |
| What is sampling rate | the rate that DAC converts digital data into analogue voltage |
| A music file will be sampled 44100 times per sec, each sample rate is 16 bits, it is stereophonic. | 44100*16*2=1211200 bits per sec |
| What things are stereophonic and how does it affect calculation | music, you have to multiply by 2 |
| What is the definition of flat panel display screen | a screen that displays image generated by computer |
| What are the two types of flat-panel display screen | Cold-cathode fluorescent lamp (CCFL), light emitting diode (LED) |
| What is the front layer of LCD screen made up of? | liquid crystal diodes, diodes are grouped in 3's and 4's which are called pixels |
| What method does LCD use | Cold-cathode fluorescent lamp (CCFL) technologies back-lighting method |
| What is the definition of LED | LED uses matrix of tiny LED behind LCD screen |
| How is LED technology better than CCFL | last longer, brighter lights, less energy, thinner |
| What is LED made up of | organic materials, carbon compounds, plastic |
| What is the definition of projectors | a device that displays computer output onto wall |
| What are the two types of projectors | Digital Light Projectors (DLP), Liquid Crystal Display (LCD) |
| What is the definition of DLP | millions of micro-mirrors on a chip. When microprocessor is tilted-towards light source, they are on. |
| How does a DLP work | 1. bright white light source passes through colour filter to DLP chip
2. light is split into 3 colours (red,green,blue)
3. on and off states of mirror link to colors to produce coloured image |
| How does a LCD projector work? | 1. beam of white light generated from bulb of LED in projector
2. beam sent to group of chromatic -coated mirrors, which reflect back at diffferent wavelength corresponding to 3 light component
3. colour component passes through 3 LCD screen and color of grey image emerges
4. combine prism to produce millions of colours |
