TV shows have become more and more colorful and interactive. They have given viewers greater visual impact. The background of the programs has played an important role. In recent years, LED display screens and DLP splicing screens have gradually become the mainstream of the program background. This article intends to do some analysis and discussion on the technical features, use effects, advantages and disadvantages, and precautions of the two types of display screens.
First, LED display
LED is the abbreviation of LightEmittingDiode. Chinese means light emitting diode. It is a solid-state semiconductor device that can directly convert electrical energy into light energy. LED display is an advanced digital information product. It successfully integrates computer technology, network communication technology, image processing technology, embedded control technology, etc. It has flexible display area and resolution (modular assembly can be arbitrary), high With the advantages of brightness, low power consumption, long life, low heat, environmental protection, and durability, the company has comprehensively used sound, light, electricity, maps and texts, and is an end product that displays information in an all-round and perfect manner.
LED displays are increasingly used in large-scale events in television studios and television broadcasts. As a stage backdrop, it provides a variety of lively, dazzling background images and more interactive features, so that the background image is also static This blends the performance with the background and gives people an immersive feeling. It brings more space to the spectacle of ceremonies, designing a modern and visually striking stage that perfectly integrates the atmosphere of the scene and the program, realizing the functions and effects that are difficult to achieve for other stage art equipment.
The audience's viewing effects and feelings of the LED display are very intuitive, and as long as the screen size, pixel pitch and viewing distance are appropriate, such a direct-view display can obtain excellent results. However, the number of viewers in front of the TV is far greater than the number of on-site viewers. Therefore, the viewing effect of the TV in front of the audience is the focus of TV technical workers' research and discussion. Many Taiwanese have used LED display screens, but the effects of the TV screens are very different. Some of the screens are bright and clear and stable from beginning to end; some are not clear at long-distance viewing, or are highlights of some activities at close quarters, or they are Dirty fringe interference, in some characters close-ups, often appear moire interference, disrupting the audience's line of sight.
During the selection and use of LED display screens, the following aspects must be noted:
1. The distance between the dots should be as small as possible The distance between the center points of adjacent pixels of the LED display. The smaller the dot pitch, the more pixels per unit area, the higher the resolution, and the closer the shooting distance, of course, the more expensive it is. At present, the dot spacing of LED displays used in studios in domestic TV stations is mostly 6-8 mm. To achieve excellent results, buy LED screens to find Shenzhen Yuanxu Optoelectronics Manufacturing Experts! It is necessary to carefully study the relationship between the resolution of the signal source and the distance between points, strive to achieve consistent resolution, and achieve point-to-point display, so as to achieve good results.
2. Fill factor to be higher Fill factor of the LED display screen (FillFactor), also known as the bright area ratio, that is, the ratio of the light emitting area of ​​each pixel to the physical surface area occupied by the pixel. The LED display is made up of discrete pixels arranged with a distinct non-emissive black area between the pixels. When viewing at close range, the picture is incoherent and the brightness is uneven. If the light source is limited to a very small pixel surface area, the brightness of a single pixel is several times or even more than ten times the brightness of the entire screen. Causes a more serious stigma. Flat panel display industry recognized TCO'99 standard, fill factor should not be less than 50%, the current market, many LED display screen fill factor does not reach this target. The cut-off characteristic of the low-pass filter of the TV also directly affects the suitable shooting distance of LED display screens with different fill factors.
Since LED displays with the same dot pitch have a large fill factor with a larger attenuation than the fill factor, the shooting distance needs to be increased. If the system lowpass filter passband is 4MHz and the attenuation characteristic of high frequency is 12db/octave, then the shooting distance of 25% of the fill factor is more than 1.15dB attenuation than the fill factor of 50%, and the shooting distance needs to be increased by about 10%. . The increase of the fill factor makes the viewing angle of the display more broad, and the color mixing effect is more ideal. It overcomes the glare problem of the pixels and also creates the conditions for appropriately improving the brightness of the entire screen to obtain better results. Jiangsu Education Station selected a 60% LED display with a moderately soft brightness, uniform bright colors, and clear and expressive performance to ensure the high quality of the display screen.
3. Color temperature The ability to adjust the color temperature (ColorTemperature) is determined by comparing the shape of the emitter emission spectrum with the fitted blackbody emission spectrum shape. When using the LED display as a background in the studio, buy an LED screen to find Shenzhen Yuanxu Optoelectronics Manufacturing Expert! The color temperature should be the same as the color temperature of the lighting in the studio to get accurate color reproduction during shooting. The studio lighting according to program needs, sometimes use 3200K low color temperature lamps, sometimes use 5600K high color temperature lamps, LED display need to be adjusted to the corresponding color temperature, in order to obtain satisfactory shooting results.
4. Shooting distance should be appropriate As mentioned earlier, the distance between points and fill factor mentioned, different point spacing, different fill factor LED display, the appropriate shooting distance is not the same. The distance between the person being photographed and the screen is appropriate in the range of 4 to 10 meters, so that when you take a picture of a person, you can get a relatively good background picture. If the character is too close to the screen, the background will appear grainy when the close shot is taken, and moire is also likely to occur.
5. Ensure a good use of the environment The product has only a low failure rate during the service life only under suitable working conditions. The LED display is an integrated electronic product. It is mainly composed of a control board with electronic components, a switching power supply, and a light emitting device. The life and stability of all these components are closely related to the operating temperature. If the actual operating temperature exceeds the product's specified range of use, not only its life will be shortened, but also the product itself will be severely damaged. In addition, the threat of dust can not be ignored. Working in a dusty environment, due to the PCB adsorbing dust, and the deposition of dust will affect the heat dissipation of electronic components, will cause the temperature of the components to rise, and then there will be a drop in thermal stability or even leakage, and in severe cases it will lead to burn. Dust also absorbs moisture and corrodes electronic circuits, causing some short-circuit problems that are not easy to troubleshoot. Pay attention to keeping the studio clean. Studio renovation will produce a lot of dust, need to do a good job of protecting the LED display in advance.
The use of LED display screens greatly enriches the display format of the program background. LED display screens are suitable for large-scale variety shows of large scenes and large studios.
Second, DLP splicing screen DLP is the abbreviation of DigitalLightProcessing, the Chinese meaning for digital light processing, this technology is the first image signal after digital processing, and then projected light. From the technical principle of DLP, it has advantages such as less signal noise, accurate gray scale, higher reflectivity, seamless image display, and high reliability. The DLP splicing screen is made up of a plurality of rear projection display units. Its main feature is that the seams are small and can be controlled within 0.5 mm. Everyone calls it "seamless" splicing. This is also the other two major technologies LCD and PDP. Unable to reach. Due to its advantages, TV stations have used DLP splicing screens as the background of studios in recent years. CNN, BBC, SKY, CCTV and other well-known big TV stations have achieved excellent results after they are used.
DLP splicing screens also have disadvantages. Because the light source of the DLP splicing is from the light bulb, its power consumption is large, the heat dissipation is high, and the brightness will be reduced after a period of use. The user must constantly change the light bulb to maintain the initial display effect. With the development of technology, thanks to the addition of LED light sources, the current DLP splicing screen has solved a series of problems such as frequent bulb replacement, high power consumption, and high heat dissipation. The DLP splicing screen after the LED light source has not only achieved a major breakthrough in the service life and power consumption, but also has a revolutionary change in the color, so that the DLP splicing screen continues to maintain the market advantage.
In order to achieve a satisfactory TV effect, we must pay attention to the following aspects in the selection and use of DLP splicing screens:
1. Splicing gaps should be as small as possible. The background display we want on the TV is seamless. This requires the splicing gap to be small enough to see no gaps in the lens. At present, the use of titanium alloy stitching technology can reduce the splicing gap to less than 0.2 mm. At the same time, the connecting plate design can ensure that the screen does not deform during thermal expansion and contraction, providing excellent image geometry and sharpness for the entire screen.
2. Higher uniformity The DLP splicing screen is made by splicing multiple display screens, resulting in individual differences in each screen. We hope that they look like a large display screen with matching colors and brightness. Need to improve uniformity by technical means. At present, this technology is relatively mature, and the advanced technology manufacturers have been able to operate in the silent mode in the background without operator intervention. It integrates proprietary brightness and color sensors to continuously measure the color and brightness of the screen wall and between the projection modules. Communication, automatic matching all white, all black and all the gray level brightness and all the display module color between the two, and to maintain the same gray level of the entire display, so as to achieve long-term image consistency under multi-screen mosaic.
3. The color temperature needs to be adjusted like the LED display screen. The color temperature of the DLP splicing screen needs to be consistent with the color temperature of the lighting in the studio to ensure the true reduction of the image color.
4. Studio lighting to control the DLP splicing screen compared to other displays, the brightness is relatively low, which requires control of the studio lighting, to avoid direct light to the screen. After researching and exploring, we used a cold light fixture with a 20° grid to effectively control the illuminance on the screen to within 100 lux, and ensure that the luminosity of the host's surface can reach 800-1000 lux. Effect.
5. The light source needs high security. The interaction of live TV is getting stronger and stronger, and the security requirements for the background are getting higher and higher. The single screen size of the DLP splicing screen is larger. If there is a problem with the light source, it causes a black screen. The negative impact on this program and even one station will be great. Therefore, it is necessary to use a dual-lamp hot backup or a redundant LED module as a light source.
6. To ensure good heat dissipation, but also to control the noise UHP bulbs and LED light source will produce a lot of heat during the work, its heat is to ensure the life of the light source and an important part of the normal work, advanced liquid cooling technology can make the cooling efficiency Higher, less noise, but also pay attention to maintain a good ambient temperature, can not immediately cut off the power at shutdown, let the cooling system continue to run for a period of time, so that the light source is fully cooled and then cut off the power, which plays a good light source The role of protection to make it work when it works.
DLP splicing screen is a revolution in the studio background, but due to its high lighting requirements, it is not suitable for use in large-scale variety shows. It is suitable for news, interviews, live connection, weather forecast, etc. in small and medium-sized studios. Types of shows. Buy LED screen to find Shenzhen Yuan Xu photoelectric manufacturing experts!
With the development of technology, more new technologies and new ways will be applied to the studio background. We need to understand their characteristics in depth, select technical products as background for different studio conditions, program forms, and requirements, so that these new technologies will give full play to their advantages, better serve programs, and serve the audience.
First, LED display
LED is the abbreviation of LightEmittingDiode. Chinese means light emitting diode. It is a solid-state semiconductor device that can directly convert electrical energy into light energy. LED display is an advanced digital information product. It successfully integrates computer technology, network communication technology, image processing technology, embedded control technology, etc. It has flexible display area and resolution (modular assembly can be arbitrary), high With the advantages of brightness, low power consumption, long life, low heat, environmental protection, and durability, the company has comprehensively used sound, light, electricity, maps and texts, and is an end product that displays information in an all-round and perfect manner.
LED displays are increasingly used in large-scale events in television studios and television broadcasts. As a stage backdrop, it provides a variety of lively, dazzling background images and more interactive features, so that the background image is also static This blends the performance with the background and gives people an immersive feeling. It brings more space to the spectacle of ceremonies, designing a modern and visually striking stage that perfectly integrates the atmosphere of the scene and the program, realizing the functions and effects that are difficult to achieve for other stage art equipment.
The audience's viewing effects and feelings of the LED display are very intuitive, and as long as the screen size, pixel pitch and viewing distance are appropriate, such a direct-view display can obtain excellent results. However, the number of viewers in front of the TV is far greater than the number of on-site viewers. Therefore, the viewing effect of the TV in front of the audience is the focus of TV technical workers' research and discussion. Many Taiwanese have used LED display screens, but the effects of the TV screens are very different. Some of the screens are bright and clear and stable from beginning to end; some are not clear at long-distance viewing, or are highlights of some activities at close quarters, or they are Dirty fringe interference, in some characters close-ups, often appear moire interference, disrupting the audience's line of sight.
During the selection and use of LED display screens, the following aspects must be noted:
1. The distance between the dots should be as small as possible The distance between the center points of adjacent pixels of the LED display. The smaller the dot pitch, the more pixels per unit area, the higher the resolution, and the closer the shooting distance, of course, the more expensive it is. At present, the dot spacing of LED displays used in studios in domestic TV stations is mostly 6-8 mm. To achieve excellent results, buy LED screens to find Shenzhen Yuanxu Optoelectronics Manufacturing Experts! It is necessary to carefully study the relationship between the resolution of the signal source and the distance between points, strive to achieve consistent resolution, and achieve point-to-point display, so as to achieve good results.
2. Fill factor to be higher Fill factor of the LED display screen (FillFactor), also known as the bright area ratio, that is, the ratio of the light emitting area of ​​each pixel to the physical surface area occupied by the pixel. The LED display is made up of discrete pixels arranged with a distinct non-emissive black area between the pixels. When viewing at close range, the picture is incoherent and the brightness is uneven. If the light source is limited to a very small pixel surface area, the brightness of a single pixel is several times or even more than ten times the brightness of the entire screen. Causes a more serious stigma. Flat panel display industry recognized TCO'99 standard, fill factor should not be less than 50%, the current market, many LED display screen fill factor does not reach this target. The cut-off characteristic of the low-pass filter of the TV also directly affects the suitable shooting distance of LED display screens with different fill factors.
Since LED displays with the same dot pitch have a large fill factor with a larger attenuation than the fill factor, the shooting distance needs to be increased. If the system lowpass filter passband is 4MHz and the attenuation characteristic of high frequency is 12db/octave, then the shooting distance of 25% of the fill factor is more than 1.15dB attenuation than the fill factor of 50%, and the shooting distance needs to be increased by about 10%. . The increase of the fill factor makes the viewing angle of the display more broad, and the color mixing effect is more ideal. It overcomes the glare problem of the pixels and also creates the conditions for appropriately improving the brightness of the entire screen to obtain better results. Jiangsu Education Station selected a 60% LED display with a moderately soft brightness, uniform bright colors, and clear and expressive performance to ensure the high quality of the display screen.
3. Color temperature The ability to adjust the color temperature (ColorTemperature) is determined by comparing the shape of the emitter emission spectrum with the fitted blackbody emission spectrum shape. When using the LED display as a background in the studio, buy an LED screen to find Shenzhen Yuanxu Optoelectronics Manufacturing Expert! The color temperature should be the same as the color temperature of the lighting in the studio to get accurate color reproduction during shooting. The studio lighting according to program needs, sometimes use 3200K low color temperature lamps, sometimes use 5600K high color temperature lamps, LED display need to be adjusted to the corresponding color temperature, in order to obtain satisfactory shooting results.
4. Shooting distance should be appropriate As mentioned earlier, the distance between points and fill factor mentioned, different point spacing, different fill factor LED display, the appropriate shooting distance is not the same. The distance between the person being photographed and the screen is appropriate in the range of 4 to 10 meters, so that when you take a picture of a person, you can get a relatively good background picture. If the character is too close to the screen, the background will appear grainy when the close shot is taken, and moire is also likely to occur.
5. Ensure a good use of the environment The product has only a low failure rate during the service life only under suitable working conditions. The LED display is an integrated electronic product. It is mainly composed of a control board with electronic components, a switching power supply, and a light emitting device. The life and stability of all these components are closely related to the operating temperature. If the actual operating temperature exceeds the product's specified range of use, not only its life will be shortened, but also the product itself will be severely damaged. In addition, the threat of dust can not be ignored. Working in a dusty environment, due to the PCB adsorbing dust, and the deposition of dust will affect the heat dissipation of electronic components, will cause the temperature of the components to rise, and then there will be a drop in thermal stability or even leakage, and in severe cases it will lead to burn. Dust also absorbs moisture and corrodes electronic circuits, causing some short-circuit problems that are not easy to troubleshoot. Pay attention to keeping the studio clean. Studio renovation will produce a lot of dust, need to do a good job of protecting the LED display in advance.
The use of LED display screens greatly enriches the display format of the program background. LED display screens are suitable for large-scale variety shows of large scenes and large studios.
Second, DLP splicing screen DLP is the abbreviation of DigitalLightProcessing, the Chinese meaning for digital light processing, this technology is the first image signal after digital processing, and then projected light. From the technical principle of DLP, it has advantages such as less signal noise, accurate gray scale, higher reflectivity, seamless image display, and high reliability. The DLP splicing screen is made up of a plurality of rear projection display units. Its main feature is that the seams are small and can be controlled within 0.5 mm. Everyone calls it "seamless" splicing. This is also the other two major technologies LCD and PDP. Unable to reach. Due to its advantages, TV stations have used DLP splicing screens as the background of studios in recent years. CNN, BBC, SKY, CCTV and other well-known big TV stations have achieved excellent results after they are used.
DLP splicing screens also have disadvantages. Because the light source of the DLP splicing is from the light bulb, its power consumption is large, the heat dissipation is high, and the brightness will be reduced after a period of use. The user must constantly change the light bulb to maintain the initial display effect. With the development of technology, thanks to the addition of LED light sources, the current DLP splicing screen has solved a series of problems such as frequent bulb replacement, high power consumption, and high heat dissipation. The DLP splicing screen after the LED light source has not only achieved a major breakthrough in the service life and power consumption, but also has a revolutionary change in the color, so that the DLP splicing screen continues to maintain the market advantage.
In order to achieve a satisfactory TV effect, we must pay attention to the following aspects in the selection and use of DLP splicing screens:
1. Splicing gaps should be as small as possible. The background display we want on the TV is seamless. This requires the splicing gap to be small enough to see no gaps in the lens. At present, the use of titanium alloy stitching technology can reduce the splicing gap to less than 0.2 mm. At the same time, the connecting plate design can ensure that the screen does not deform during thermal expansion and contraction, providing excellent image geometry and sharpness for the entire screen.
2. Higher uniformity The DLP splicing screen is made by splicing multiple display screens, resulting in individual differences in each screen. We hope that they look like a large display screen with matching colors and brightness. Need to improve uniformity by technical means. At present, this technology is relatively mature, and the advanced technology manufacturers have been able to operate in the silent mode in the background without operator intervention. It integrates proprietary brightness and color sensors to continuously measure the color and brightness of the screen wall and between the projection modules. Communication, automatic matching all white, all black and all the gray level brightness and all the display module color between the two, and to maintain the same gray level of the entire display, so as to achieve long-term image consistency under multi-screen mosaic.
3. The color temperature needs to be adjusted like the LED display screen. The color temperature of the DLP splicing screen needs to be consistent with the color temperature of the lighting in the studio to ensure the true reduction of the image color.
4. Studio lighting to control the DLP splicing screen compared to other displays, the brightness is relatively low, which requires control of the studio lighting, to avoid direct light to the screen. After researching and exploring, we used a cold light fixture with a 20° grid to effectively control the illuminance on the screen to within 100 lux, and ensure that the luminosity of the host's surface can reach 800-1000 lux. Effect.
5. The light source needs high security. The interaction of live TV is getting stronger and stronger, and the security requirements for the background are getting higher and higher. The single screen size of the DLP splicing screen is larger. If there is a problem with the light source, it causes a black screen. The negative impact on this program and even one station will be great. Therefore, it is necessary to use a dual-lamp hot backup or a redundant LED module as a light source.
6. To ensure good heat dissipation, but also to control the noise UHP bulbs and LED light source will produce a lot of heat during the work, its heat is to ensure the life of the light source and an important part of the normal work, advanced liquid cooling technology can make the cooling efficiency Higher, less noise, but also pay attention to maintain a good ambient temperature, can not immediately cut off the power at shutdown, let the cooling system continue to run for a period of time, so that the light source is fully cooled and then cut off the power, which plays a good light source The role of protection to make it work when it works.
DLP splicing screen is a revolution in the studio background, but due to its high lighting requirements, it is not suitable for use in large-scale variety shows. It is suitable for news, interviews, live connection, weather forecast, etc. in small and medium-sized studios. Types of shows. Buy LED screen to find Shenzhen Yuan Xu photoelectric manufacturing experts!
With the development of technology, more new technologies and new ways will be applied to the studio background. We need to understand their characteristics in depth, select technical products as background for different studio conditions, program forms, and requirements, so that these new technologies will give full play to their advantages, better serve programs, and serve the audience.
HUATAO GROUP is a professional enterprise specializing in the production of paper mchine clothings from China. The company has a professional, refined, vibrant first-class team to supply Spiral Dryer Canvas,poleyster spiral mesh, Papermaking Wire,sprial dryer fabric,for packing paper machine,craft paper machine,wrintting and printing paper machine,paperboard paper machine ect ,all kinds of dryer fabric for paper industry.
Dryer Fabrics,Dryer Screen,Spiral Dryer Canvas,Polyester Spiral Belt,Sldf,Spiral Dryer Fabric
HUATAO GROUP LTD , https://www.huataogroup.com