A plus 220-1001 – Exam Objective 1.2
A+ Exam Objective 1.2
1.2 Given a scenario, install components within the display of a laptop.
Wi-Fi antenna connector/placement
Welcome to ExamNotes by CertBlaster! Here we will look at what you need to know to satisfy A+ 220-1001 sub-objective 1.2. We will examine the functions available and the features of a laptop display panel. While most of us think of it as simply “the lid”, more and more features are finding their way into the laptop display panel. We will begin by examining the types of displays available for the laptop display. The display type can provide space for other components without adding size. Laptop displays break down into two main types: LCD and OLED. These display types can be defined further by their characteristics.
LCD is a term that has had its definition evolved as the technology has improved. The basic LCD design consists of a liquid crystal material sandwiched between two clear plastic sheets with a light source behind the package. The liquid crystal material is divided into small squares.
Each square is independent of the others and each is capable of 32-bit color depth. These squares are referred to as pixels and many monitors are classified by its monitor pixel count, that is, how many pixels wide and how many pixels high is the screen’s resolution. For example, you may see a display listed as 1680×1050. This indicates that there are 1,680 independent rows of pixels arranged horizontally on the display and 1,050 rows of pixels arranged vertically. You may also see values such as DPI (Dots per Inch). With DPI, more is better. Here is a great comparison of how pixels have been and are used to provide imperceptibly clean images. Remember, these images are greatly magnified.
Pixel geometry (This image was created by Pengo, many thanks!)
The time it takes a pixel to respond to a changed value is known as the response time. The response time is defined as the time it takes a pixel to change from completely black to completely white, and then return back to black. The response time is measured in milliseconds. Response times vary from 1ms to 11ms. The monitor’s cost varies according to its response time. Use these numbers to ballpark the monitors you are choosing. Often, the response time measurement is instead the response time for the pixel to go from grey to white to grey. In addition, with no true definition of grey, these measurements are highly inconsistent. Instead, use your eyes and look for ghosting and viewing angle when selecting a monitor.
TTL vs. IPS
There are three technologies used in LCDs: TN, TTL, and IPS. Let’s familiarize ourselves with these three technologies.
TN – Twisted Nematic (TN) screens have exceptional response times, brighter colors, and crisp imaging. The downside to this technology is that they use considerably more power while providing a restricted viewing angle compared to the other types.
TTL – describes a digital circuit that uses Transistor Translator Logic (TTL). The term has also been used to describe monitors that accept digital signals as opposed to analog signals such as composite or component.
IPS – In-Plane Switching (IPS) technology provides an enhanced viewing experience when compared to the other display types. IPS offers truer colors and an expanded viewing angle when compared to the others.
Fluorescent vs. LED backlighting
For all the previously discussed screen technologies, keep in mind that there is no light emitted from the screens themselves. Like a photographic “negative” or a projector slide, the screens need illumination for us to see the image. That is where the concept of backlights comes in. Two types of backlights are shown below.
CCFL – Cold Cathode Fluorescent Light (CCFL), or its common name fluorescent light, is simply a fluorescent light placed behind the display. Multiple lights can be used but each one requires its own Inverter board. The Inverter converts DC current into AC current to power the bulb. If two lights are used, two inverters are required to power them.
LED – Light Emitting Diodes (LED) are quite bright and very efficient in terms of energy consumption. LEDs are also environmentally friendly. One of the reasons for their efficiency comes from the fact that the power does not have to be “inverted” for use. The LED is able to use DC power straight from the motherboard with no waste. In addition, LEDs themselves are small, efficient, and quite bright. When placed behind the LCD, they produce bright accurate color. Here are images of a LED panel and a CRT monitor display. Both are highly magnified for detail but the similarity is evident.
Another type of display is the OLED (Organic Light – Emitting Diode) which uses a thin LED film of organic material sandwiched between two electrode grids. There’s no backlight and the lower light produced by the LED film allows for better contrast and deep blacks. This display type is best suited to low light environments where you can see the benefits of the technology.
What’s in the lid?
We’ve examined the types of technology used in laptop displays, but the lid also contains some other necessary items that make sense being in the lid.
Your Wi-Fi antenna benefits greatly in range and performance if you can get it up in the air an extra foot or two. Putting the Wi-Fi antenna in the lid makes a lot of sense.
Webcam & Microphone
When it comes to webcam and microphone placement, the laptop lid is the ideal location. This makes videoconferencing or chatting much more natural.
A digitizer is a device, or even an overlay on your LCD panel, that takes physical input, such as finger or stylus movement, and converts it digitally on your display. For example, this device makes it possible to draw directly into a graphics program. This is a great accessory for a graphic artist and provides him/her the opportunity to create and digitally modify their creations. The digitizer can be considered a touchscreen.
And that friends, is it for 220-1001 1.2. Not a lot but you need to know it! Good luck on the exam!