Weak current College】 【basic parameters screen.

<br> 1. gain <br> <br> Screen incident light. In the incident light angle must, the incident light flux invariable, screen brightness in one direction and ideally brightness ratio is called the direction of luminance coefficient, the maximum value is .called the gain of the screen. Usually the matte white walls of the gain is set at 1, if the screen increases is less than 1, will weaken the incident light; if the screen increases is greater than 1, the reflection or refraction more incident .light. <br> <br> 2. perspective <br> <br> Screen in all directions of reflection is different, and in the horizontal direction from the center of the screen, the lower the further brightness; when the brightness is reduced to .50% of the viewing angle, defined as the angle of view. View images in perspective, brightness within satisfactory; in addition to the viewing angle, the image brightness is not enough. Generally speaking, the higher the gain of the screen, the smaller .the angle (metal curtain), gain, the greater the angle of view (white plastic curtain), for a higher number of occasions, use white plastic curtain expanded perspective. <br> <br> Size 3, <br> <br> .Screen size is the size of the diagonal. General video image aspect ratio is 4: 3, the Education Act as squares. If a 1.83m (72-inch) screen, based on the Pythagorean theorem, we'll draw the screen width to .height 1.1m 1.5m,. <br> <br> 4. solar energy utilization <br> <br> For rear projection screen, is the light transmission rate; for front projection screen, is the reflectivity, nature is the higher the better .. On the projection screen, structured screen than scattering curtain much better. For example, to obtain the same brightness, scattering curtain users buy 8 million projectors, structured screen users as long as 5 million of the projector. <br> <br> 5 .. resolution of the screen (resolution): <br> <br> In response to the current international different projector type, image resolution based primarily on the type of projector: CRT technology and LCD, DLP, and LCOS technology into D-ILA, .bandwidth and pixels. Pixel: pixel mean resolution height pixel multiplied by the number of results, the main measure LCD / DLP / D-ILA / LCOS technology projectors. At the same time means the true resolution projectors. Bandwidth: measuring CRT projector per second .scan horizontal frequency. Fresnel optics rear projection (projector behind the screen, projector and viewers on both sides of the screen respectively in the direction of the projection mode) shadow screen because the Fresnel lens Groove and surface double convex (columnar) lens pitch lines, .has a direct impact on the resolution of the screen. For diffuse backlight hard curtain, Cork and the projection screen, no Groove spacing of lines of resolution is very high, and meet the needs of the high resolution screen. <br> <br> .6, the contrast of the screen: <br> <br> Contrast: contrast for images of uniformity and resolution is important primarily means a high level and low level of popular is the screen light areas and dark areas of the ratio. High-contrast .screen for hierarchical display screen is crucial, to this end, the internationally famous screen company Stewart (view erte) screen company launched different colored soft, hard screen so that the screen display more colourful. <br> <br> 7, screen uniformity: .<br> <br> The homogeneity of the screen: the screen uniformity is not only manifested in the screen above, but also of quality and projector projection technology. Good uniformity can ensure screen horizontally, vertically, from 0-180 ° watch, screen .brightness, and color consistency. Screen surface material for uniformity on the projector screen uniformity played a good complement. Finally, the screen from the site system, the screen also play a good complement to cover of the projection screen, the aspect ratio will be on .the screen, the aspect ratio of the screen is different even broader application in several environments, screen ratio between free conversion. <br> <br> 8. the relationship between gain and perspective <br> <br> In General, the projection screen .of gain and perspective is a rightness of Antinomies, under certain conditions the same perspective, the higher the gain, whereas the larger lower gain perspective. So gain constant increase the angle of view or in the same increase the gain is a projection screen and development .experts continually research, experimental and needs to be addressed. Metal soft curtain Rd experts by continuously adjusting the metal reflection coating formulations and screen-based production process, without lowering the brightness gain by increasing the angle of view. The current metal soft screen angle Max .110 ° has been reached. But people find looking at 40 ¡ .ã appearance, image has begun deformation; look at 80 °, the image is distorted meaningless. <br> <br> 9, the relationship between the distance and the brightness (luminance × area = brightness) <br> <br> The closer .the distance light source, the more light, the farther away the more dark, everyone knows the basics of. Similarly, a projection display areas, the same projector and the same screen hit the same distance from different on the screen, the screen's brightness is .different. In other words, the same projector and screen to play full screen in different sizes, different because of its distance, the brightness of the screen is different. But the same projector and screen play in different gain of the screen is completely different. .Experts test: use the same brand, same model, same as factory and the same test of the projector screen to play in the gain of 2, plain screen and the gains for the 4 of us-invasive metal soft curtain, two different from the .screen, its brightness gain totally different, gain higher screen brightness too high. <br> <br> <br>.