About the knowledge of television, television will never be strange to us. We often watch it in our spare time, but many people don't know much about TV. Here are some related knowledge about TV for you.
About TV 1 1, what is brightness? What is the function of brightness?
Brightness refers to the brightness of a TV set under a white screen, and the unit is candela per square meter (cd/m2) or nits.
High brightness: clear picture display, richer layers and long service life of TV. Low brightness: the picture display is blurred, the layering is poor, and the service life of the TV is short.
2. What is contrast? What is the function of contrast?
A. Static contrast refers to the ratio of the brightness of the brightest (white) to the darkest (black) at the same point on the screen. Contrast can reflect the level from black to white.
B. Dynamic comparison usually refers to; The ratio of the brightest white to the darkest black in a series of TV pictures is expressed in the same way as contrast. Dynamic contrast is usually higher than static contrast.
The greater the contrast, the clearer and more striking the image, the more vivid and gorgeous the color.
There are two methods to measure contrast: one is to measure the brightness ratio of full-screen white to full-screen black;
3. What is color temperature?
You can adjust the white scene to warm color (reddish), plain color (blue) or natural state (standard).
4. What is fixed resolution?
Fixed resolution refers to the number of pixels on the screen and the smallest unit that constitutes an image. Television images are mainly produced by many stacked pixels, so the number of pixels is an important factor affecting the resolution. Resolution is one of the main standards of TV.
5. What is the response time?
Response time is a specific indicator of LCD TV, which refers to the response speed of each pixel to the input signal in milliseconds (ms). The shorter the response time, the faster the pixel response. However, if the response time is too long, when displaying dynamic images (even the cursor of the mouse), it will produce a serious tailing phenomenon.
6. Screen size: determined by the diagonal size. The aspect ratio of the screen is 4: 3, 16: 9.
Maximum resolution: Also known as the maximum displayable resolution, it refers to the highest resolution of the input signal that the projector can display.
Through the image processing algorithm, the projector can scale the input signal and realize the full-screen display of the signal. If it exceeds this range, the projector will not be able to display the picture normally.
7. What's wrong with it?
The bad dot of LCD, also called dot missing, refers to the sub-pixel points displayed in black and white and red, yellow and blue, and each point refers to a sub-pixel. The LCD screen is most afraid of bad points. Once a bad dot appears, no matter what image is displayed on the display screen, a certain point on the display screen will always display the same color. This "bad point" can't be repaired. Only by replacing the whole display can the problem be solved.
Bad spots can be roughly divided into two categories, in which dark spots are black spots that can't display content no matter how the content displayed on the screen changes, and the most annoying thing is the bright spots that always exist as long as the screen is turned on.
8. What is noise reduction? What is its function?
Noise reduction refers to filtering the noise signal in the image, which can suppress noise points and filter out clutter.
Make the picture clearer and neater, and the effect is obvious when the signal is weak.
9. What is VM speed modulation? (SVM) What is its function?
By controlling the scanning speed of electron beam, the deterioration of image signal-to-noise ratio caused by high brightness of TV is overcome. The main function is to overcome the blurring of image contour edges and improve the burr phenomenon of image lines and text edges. SVM is an improved version of VM.
10, what is DCDI diagonal compensation processing technology? (Anti-aliasing of image edges)
It is a unique patent technology for detail compensation of moving images. Tracking, detecting and interpolating the edge of the moving image can completely eliminate the step-like sawtooth when the moving image is displayed line by line, and make the edge of the image smooth and natural.
1 1. What is CCS digital crosstalk suppression technology?
By comparing the differences between the two scanning signals, the brightness signal of each picture can be clearly distinguished from the horizontal, vertical and diagonal directions, from which clutter, spots and color overlap in the signal can be effectively eliminated and the image quality can be effectively improved.
12, what is a black bottom pipe?
The gap between the fluorescent surface and the fluorescent spot is filled with a black substance that does not emit light. From the outside, the screen looks black, which reduces the reflectivity of the fluorescent surface to external light by about 50%. Greatly improve the image contrast.
13, what are the four major pieces of cRT color TV?
Picture tube, line output transformer, tuner, integrated circuit (IC or integrated block)
What is a tuner? What is a single high frequency? What is dual high frequency?
A tuner is a tuner that receives TV signals.
Single high frequency: Picture-in-picture function, big screen plays TV signals, small screen only plays discs, not two TV programs at the same time.
Double high frequency: Picture-in-picture function (double window), which can play TV programs of different channels freely at the same time.
What is the standard? How many standards are there?
System is the way of signal composition and transmission. (The composition method determines a variety of delivery methods. Broadcast mode is a system. )
There are 28 formats in the world:
It is divided into three categories: PAL system, NTSC system and SECAM.
(1) image system
NTSC standard: 60HZ interlaced scanning .525 lines; This image system is used in North America, Japan and Taiwan Province Province.
PAL system: 50HZ interlaced scanning .625 lines, used in Europe and most parts of Asia.
SECAM system: This image system is used in France, Eastern Europe, Russia and Africa.
(2) Sound system
D/K system: This sound system is used in Chinese mainland with sound carrier frequency of 6.5MHZ.
I system: sound carrier frequency is 6.0MHZ；; China and Hongkong use this audio system.
BG system: sound carrier frequency is 5.5MHZ；; This kind of sound system is used in European countries such as Russia.
M system: the sound carrier frequency is 4.5MHZ；; Japan and the United States use this audio system.
15. What is a super bass?
Make the bass sound richer, more powerful and more shocking.
16. What is BBE sound enhancement technology? (Listening to music)
It is a professional audio technology developed by American BBE sound Company. So as to reproduce the original sound without distortion. Can make the treble clearer, more natural, brighter and more expressive in detail; Make the bass strong, clear and rhythmic. (original flavor)
17. What is the sound enhancement technology of bbeviva?
Based on the original sound effect of BBE, 3D (three-dimensional surround sound) has been enhanced. So that the sound signal of the sound can be perfectly reproduced and restored, and the sound quality is clearer and more realistic.
What is virtual surround?
Dual speakers, realize the surround sound effect of 5. 1 channel (that is, 6 speakers), and have a strong sense of the scene.
19, what is SRS?
The patented technology of SRS, a famous American audio company, is surround sound system. Create the real effect of professional family influence. Mainly to watch blockbusters. (there is a sense of existence)
20. What is the WOW3D dynamic surround sound effect?
It is a sound system recently designed by SRS company in the United States, including the following three different sound quality effects:
SRS 3D surround to enhance the sound presence;
Focusing technology to improve the clarity of sound quality
TRUBASS technology enhances bass shock (low stress)
2 1, what is a digital five-segment equalizer?
Generally, color TV can only adjust the high and low tones.
While the five-segment equalizer is divided more finely:
120 Hz (bass)
500 Hz (bass)
1.5khz (alto)
5KHZ (medium and high pitch)
10KHZ (treble).
22. What is Li Yin? (NICAM)
It was the British BBC that developed the pulse broadcasting system. Used for multi-channel audio or multi-language broadcasting. Good sound insulation, high stereo separation, good sound quality and small distortion. Mainly used for multi-audio broadcasting in multilingual areas.
Television 2 related knowledge 1, resolution:
Resolution is an important standard to measure the performance of LCD TV. At present, the mainstream resolution parameters in the market are 1366× 768 and 1920× 1080. The definition of high-definition flat-panel TV is higher than 720 lines in both horizontal and vertical directions. Simply put, a real high-definition flat-panel TV must meet the condition that the resolution is higher than 1366× 768.
2. Response time:
Response time is also very important, which will determine whether there will be blurring and tailing when displaying high-speed dynamic pictures. Experts from purchasing partners remind everyone that the current mainstream response time of 8 milliseconds can basically meet the use requirements. Generally speaking, the faster the reaction time, the less smear and afterimage appear on LCD TV. It is best to see the actual effect of playing action movies before buying.
3. Brightness and contrast:
In fact, you can directly ignore the brightness and contrast parameters provided by the manufacturer and concentrate on your own visual experience. The method is to check the brightness and contrast of the screen display at a distance of 5 meters, pay attention to some details in dark scenes, and compare several products.
4. Size:
It is necessary to know the size of the house where the TV is placed, so as to determine which size TV should be purchased. For example, the best viewing distance of 42-inch LCD TV is 2.5 to 3.3 meters, 47-inch LCD TV is 3 to 4 meters, and 55-inch LCD TV is 4.5 to 5.5 meters. This is a size that can be selected according to the actual situation of your home.
5.HDMI interface:
HDMI interface is a digital interface that can transmit audio and video signals simultaneously. It can not only simplify the connection and reduce the connection burden, but also provide huge bandwidth for digital signal transmission. It is emphasized that the importance of this interface mainly lies in that new and future devices such as disk drives, computers and home theaters will actively adopt this interface, and it will undoubtedly achieve the best effect by connecting these devices with this interface.
6. Disadvantages:
Be sure to carefully observe whether there are bright spots and dark spots on the screen before buying. You can look for black spots when the screen is white and bright spots when the screen is black. Experts from purchasing partners tell you a trick to identify bad spots: look for black spots when the screen is all green and bright spots when the screen is all blue. Once there are bright spots or dark spots, it is very easy to see them. In addition, it is best to reach an agreement with the merchant on the problem of bad points before payment, and write it into the contract.
7. Sound quality:
Each manufacturer has its own selling points in this respect, such as surround three-dimensional surround sound, SRS virtual surround sound, BBE stereo sound effect, crossover speaker, DDAS digital dynamic sound valley, various audio decoding chips and engines.
But these things have no practical significance to ordinary consumers except that some professionals and music enthusiasts can understand them. No matter how lively the hype is, the actual effect is basically the same. Therefore, consumers should make up their minds when choosing, and it is most important to listen to the sound quality.
8. Remote control:
The most easily overlooked when choosing is the remote control. A good remote control has a strong adaptability.
Knowledge about TV 3 Children watch less TV.
Babies can watch TV quietly, and parents are not bothered. They all feel relaxed. When children are in infancy, many adults either hold their children or put them in the cradle when watching TV. Infants and young children, attracted by the sound of TV, often stare at the TV sideways.
Keeping the same posture often may cause strabismus. Watching TV for a long time or watching TV with inappropriate distance, light and posture will affect children's vision and may cause strabismus, amblyopia and myopia. Parents should avoid letting too young children watch TV.
You should open the window when you watch TV for a long time.
Many people like to close the window while watching TV, especially during the day. It will be quieter when the window is closed. Television and other visual radiation pictures can release dangerous energy. If people often close the doors and windows while watching TV, it is easy to get cancer. Especially in the video room, the TV is on, the doors and windows are closed, and the curtains are pulled down. It is even more dangerous if the air conditioner is on.
However, there is no need to worry too much. If you just watch TV 1 or 2 hours with the doors and windows closed, the danger is not great. It is only dangerous to turn on the TV and close the doors and windows for several hours. And as long as you open the window, this dangerous carcinogenic energy will disappear. So remember to open the window when watching TV for a long time, even in winter.
The correct way to watch TV
1, viewing position: The closer to the TV, the greater the stimulation, and the easier it is to cause eye fatigue. The best position is that people are 2.5 ~ 8 meters away from the TV, and the height is slightly lower than the horizon of the eyes. When it is too high, looking up is easy to cause fatigue; It is easy to get tired when it is too low, because you need to bow your head.
2, viewing time: no more than 60 minutes, you should have a rest, it is best to close your eyes and rest. It has been investigated that watching TV for more than 4 hours without rest will lose two lines of vision (0.2). Watching TV for a long time makes children prone to myopia. If you are a nearsighted child, it is best not to watch TV for more than half an hour at a time, but to rest for 10 minutes.
3, ambient brightness: the brightness of the TV and the brightness contrast around the room should not be too different, otherwise it will easily cause eye fatigue. When you turn off the lights and watch TV at night, you should keep a low-degree lamp to reduce the contrast between light and dark, and its brightness should be suitable for you to see the handwriting of books clearly. It's best to draw curtains when watching TV during the day to avoid sunlight reflecting on the screen, and the picture is not clear.
4. TV brightness: If the contrast and brightness of the TV are too large, although the image is clearer, due to the uneven brightness of light, people's vision is concentrated in bright places, which is easy to cause eye fatigue; If the contrast and brightness are too small, the color of the image is not clear and can't be seen clearly. Therefore, the brightness and contrast of TV must be adjusted moderately and softly.