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3 months ago 863.410794 868.570794 Many of the laptops we use today have an LCD display. 868.570794 871.490794 This is a liquid crystal display where there are a series of liquid crystals associated 871.490794 872.490794 with color filters. 872.490794 874.850794 And there's a backlight or light source behind all of that that shines through to give 874.850794 876.090794 us the image that's on our screen. 876.090794 878.490794 From a laptop perspective, the advantages of an LCD display is that they are lightweight 878.490794 881.050794 and use very little power and are relatively inexpensive to make, keeping the cost of the 881.050794 882.050794 laptop down. 882.050794 883.370794 There are some disadvantages with LCD displays. 883.370794 885.810794 One is that this light source in the back has to shine through to provide the color, which 885.810794 888.370794 means getting a true black can be quite difficult on an LCD display. 888.370794 890.010794 We might also have different kinds of backlights on our displays. 890.010794 891.010794 The light source may be fluorescent. 891.010794 893.050794 It may be LED or maybe some other type of light. 893.050794 895.690794 If this backlight was to fail, you can see that it's part of the display itself making 895.690794 898.090794 it relatively difficult to be able to repair or replace. 898.090794 900.050794 There are three different technologies of liquid crystal displays that you need to be aware 900.050794 901.050794 of. 901.050794 902.050794 One is the TN LCD. 902.050794 904.290794 This is the twisted pneumatic LCD, which gives us very good response times if you're a 904.290794 906.570794 gamer or you're using some application that has fast moving graphics. 906.570794 907.690794 This may be the display type for you. 907.690794 909.850794 Unfortunately, these displays often have very bad viewing angles, which means once you 909.850794 912.490794 get off to the side of the display, you'll notice there's an inversion of the color. 912.490794 915.170794 If you want the best possible view of a TN LCD, you need to be looking directly at the 915.170794 916.170794 display. 916.170794 917.970794 If you're looking for the best possible color representation on an LCD display, you 917.970794 919.290794 want to use an IPS LCD. 919.290794 920.690794 The IPS stands for in plain switching. 920.690794 922.890794 This gives you very good color representation, which is great if you're using graphics or doing 922.890794 923.890794 some type of desktop publishing. 923.890794 926.690794 But these are slightly more expensive than a TN so that extra color representation comes 926.690794 927.690794 at a bit of a cost. 927.690794 931.010794 If you like something that's in the middle between TN and IPS, you may want a vertical alignment 931.010794 932.690794 LCD or a VA display. 932.690794 934.690794 This has good color representation, but you'll find the response times are a bit slower than 934.690794 935.690794 a twisted pneumatic LCD. 935.690794 937.970794 If you have a newer device, you may be using an OLED display. 937.970794 940.490794 The OLED stands for organic light emitting diode, and it doesn't have a backlight. 940.490794 942.850794 Instead, this organic material emits light when you provide it with a current. 942.850794 945.210794 Because there's no backlight, no liquid crystals, these are very thin displays, and there's 945.210794 947.090794 no glass that you would need on the front of the display to protect it. 947.090794 950.090794 The real key is that organic material that's able to create its own light when you provide it with power. 950.090794 952.290794 And that's what allows these displays to be very light and very thin. 952.290794 954.650794 You'll find them on tablets, phones, and smart devices, not only because they provide such great 954.650794 957.450794 color representation, but because they're so light and so easy to carry. 957.450794 959.450794 One aspect of our laptop displays that we don't often think about is how they're used 959.450794 960.450794 on wireless networks. 960.450794 962.970794 When you open the laptop, your display is the highest component in that system, so it's 962.970794 964.490794 a perfect place to run your wireless antennas. 964.490794 967.050794 If you're using 802.11 Bluetooth or some other type of wireless networking, then you 967.050794 969.410794 probably have an antenna that runs to the top of your laptop display. 969.410794 971.490794 This creates some challenges when you are replacing the display, because you not only 971.490794 973.570794 have to remember to connect all of your video components, you have to remember to connect 973.570794 976.650794 all of these antenna wires as well. Here's a picture of a display, this one does look a bit damaged. 976.650794 978.970794 You can see the primary connection that we use for the video signal, but coming out of 978.970794 982.170794 the other side of the display is a white and a black wire that's used for 802.11. 982.170794 984.970794 You need to take care when replacing this display that you're following the same path that 984.970794 987.650794 the previous wires took so that you can connect all of those wireless antennas to the 987.650794 989.170794 appropriate components on the system board. 989.170794 990.290794 This is what it looks like when everything is in place. 990.290794 992.010794 You can see some antenna wires coming out of the system board. 992.010794 994.170794 They're wrapping around the system and these appear to wrap all the way into the top 994.170794 995.170794 of this particular laptop. 995.170794 997.290794 If we look closely, we can see wires that are used for the 802.11 network. 997.290794 999.170794 There are some additional wires also at the top of this display. 999.170794 1010.690794 These are the wires that are used to bring the signal from the audio and video associated with the webcam. 1010.690794 1011.970794 This makes it easy when you need to be on a zoom call. 1011.970794 1014.330794 You can simply open your laptop display and the camera built into the display will be 1014.330794 1015.330794 able to show you on the call. 1015.330794 1017.690794 Here's a better shot from this laptop, which clearly shows that this is the webcam that's 1017.690794 1020.530794 integrated into the laptop display and you can see there are holes also for the microphone 1020.530794 1021.610794 in the display as well. 1021.610794 1024.050794 We mentioned earlier that a liquid crystal display needs some type of light behind the 1024.050794 1026.290794 system to shine through so that we're able to see the images on the screen. 1026.290794 1029.130794 If you're working with an older laptop, this might be a fluorescent type of light, specifically 1029.130794 1031.250794 a CCFL or cold cathode fluorescent lamp. 1031.250794 1033.450794 These require a bit more power than the LED lights that we tend to use today and you'll 1033.450794 1036.290794 find the LED backlights are also a bit thinner, taking up a lot less space on your laptop 1036.290794 1037.290794 computer. 1037.290794 1039.170794 If you're working with an older laptop or you need to replace the display on an older laptop, 1039.170794 1041.730794 you may find that the backlight that it's using is a CCFL backlight. 1041.730794 1045.090794 Newer LCD displays might use LED lights instead of using a fluorescent lamp. 1045.090794 1047.850794 These LED lights may be around the edge of the display or they might be in a matrix such 1047.850794 1048.850794 as the one that's seen here. 1048.850794 1051.490794 These become so common that instead of people referring to this as an LCD, they often refer 1051.490794 1052.810794 to it as an LED display. 1052.810794 1055.170794 What they really be, of course, is an LED backlit LCD. 1055.170794 1057.730794 If you were to pull the front off of a display that has LED backlights, you might see the 1057.730794 1059.090794 matrix behind it looking like this. 1059.090794 1061.930794 These are strips of LED lights and you can see each one of these LED lights is in a very 1061.930794 1063.130794 large matrix behind the display. 1063.130794 1065.250794 The display is smart enough to recognize what parts of the display should be lighter or 1065.250794 1068.090794 darker and will adjust the lighting depending on what you're viewing on the screen. 1068.090794 1070.730794 If you're working on one of these older laptops with CCFL or these fluorescent backlights, 1070.730794 1072.810794 you may also find some additional components behind the screen. 1072.810794 1073.810794 These are inverters. 1073.810794 1077.090794 We use these inverters because the CCFL backlight requires AC power, but your laptop is using 1077.090794 1078.090794 DC power. 1078.090794 1080.210794 The inverters are responsible for taking that DC power, converting it to AC so that we can 1080.210794 1081.530794 power those fluorescent backlights. 1081.530794 1083.890794 One way to tell if your backlight has failed is to shine a flashlight directly at the 1083.890794 1084.890794 screen. 1084.890794 1086.730794 If you're able to make out some of the information on the screen, it's very possible that 1086.730794 1089.210794 the problem is not with the display, but with the backlight behind the display. 1089.210794 1091.730794 If this is a CCFL backlight, you may just need to replace the inverters and you be able 1091.730794 1092.730794 to restore the backlight. 1092.730794 1094.130794 On some systems you may have to replace the entire display. 1094.130794 1096.130794 You'll have to check with the documentation for your laptop to see what applies for your 1096.130794 1097.130794 particular model. 1097.130794 1100.090794 If you're using a hybrid device like this one that has a keyboard and a tablet type display, 1100.090794 1102.730794 you may be able to use a very high resolution input with this stylus. 1102.730794 1105.130794 That stylus allows you to directly draw on the screen and whatever you're pushing 1105.130794 1107.170794 on the screen is converted into digital signals in the display. 1107.170794 1110.010794 We're able to provide that conversion because inside of this display is a digitizer 1110.010794 1113.410794 that converts that analog input onto the display into digital signals that the computer can use. 1113.410794 1116.130794 The digitizer in your device may only allow for stylus input or it might also provide input 1116.130794 1117.130794 using a touchscreen. 1117.130794 1119.410794 A touchscreen digitizer takes input from our finger, converts it into a digital form to 1119.410794 1120.410794 be used by that system. 1120.410794 1122.810794 It's a very common way to get information into a laptop or tablet and we can often use 1122.810794 1125.930794 a keyboard, a stylus, or key presses all on the same system to perform this input function. 1125.930794 1129.671669 [BLANK_AUDIO]
https://www.youtube.com/watch?v=sn4B3zANQug&list=PLG49S3nxzAnnOmvg5UGVenB_qQgsh01uC&index=3
This audio excerpt provides an overview of various types of displays used in laptops, including their advantages and disadvantages. It covers the workings of LCDs (Liquid Crystal Displays), their reliance on backlights, and the differences between TN (Twisted Nematic), IPS (In-Plane Switching), and VA (Vertical Alignment) technologies. It also mentions the newer OLED (Organic Light Emitting Diode) displays, which do not require a backlight, making them thinner and lighter.
Additionally, the excerpt explains the integration of wireless antennas and webcams into laptop displays, the role of backlight technologies such as CCFL (Cold Cathode Fluorescent Lamp) and LED, and the use of inverters in older laptops. It concludes with a brief discussion on hybrid devices and digitizers, which convert analog input from a stylus or touchscreen into digital signals for the computer.