On April 1, the first laser TV industry standard in mainland China, "TV Receiving Equipment Laser Projection Display Specification", was officially implemented. This is the first "document" in the laser TV industry that "accurately defines" product features and is recognized by most companies in the industry: Obviously, after the unified opinion, the development of laser TV will be more "smooth".
For this "line mark", Da Pingjun studied it and found that more of its content is focused on the aspect of "how color TV is like" - this is obviously reasonable. However, compared with the national standard for LCD TVs and other products, it also has unique features: that is, a clear and colorful "specification" of the "brightness" index of the product!
Laser TV brightness should use "nit" instead of "lumens"
For a long time, among the many products known as laser TVs, the brightness standards are relatively confusing: the big screen jun can at least list three major standards - light source brightness, projection brightness and color TV brightness. Usually the brightness standard of the light source is 3-10 times the brightness of the projection, which is 20-100 times the brightness of the color TV; the projection brightness can also reach 6-10 times the brightness of the color TV!
The difference between the values of the three brightness parameters is so large that it may lead to consumers' "cognitive confusion" and "purchase deception" - in this regard, what the big screen Jun wants to say is that consumers can only eat dumb losses many times: because the above three brightness is not false propaganda, but only "a physical quantity with different meanings and actual existence".
In particular, when a product advertises itself as a laser TV and a color TV product, but does not use the brightness representation and logo of "color TV", it is easy to "mislead consumers". In this regard, the laser TV standard can be described as a big step forward: that is, the laser TV must use nits as the brightness standard, rather than "lumens". What is the difference between Nit and Lumen?
Da Pingjun believes that this difference is very easy to understand: that is, nitnit (also known as, candela / square meter, 1 cd / m; in the practical sense with the illuminance unit lux, English for lux, simplified as lx and Le, most of the time the effect is equivalent) is to describe the "brightness per unit area". The lumen (cd, Candela) standard is the concept of "light intensity", which is used to describe the performance of a display device, referring to the sum of all the light flux emitted by the device.
The relationship between the two can be understood as a fixed lumens standard projector, in different sizes of projection screens, the nits brightness standards provided must be different - the larger the picture, the lower the nits brightness standard: from the consumer point of view, the NITs standard is the real perceived "display effect"; the lumens standard is an "intermediate quantity" in the equipment workflow (the brightness of the light source is the "intermediate amount" in the projection equipment workflow)!
That is, Dapingjun believes that consumers can completely evaluate the visual effect of laser TV with "display screen size + nit brightness standard". However, if the vendor only gives the flow brightness of the host, the "final visual standard" becomes complicated!
How far is the lumen standard from the Nits standard
"The lumens divided by the display area, isn't it Nit?" This is the "simple logic" of many consumers. In this regard, DaPingjun would like to point out that there is nothing wrong with simply from the perspective of the ideal equipment, from the standard definition and the conversion process. However, the actual conditions are not ideal conditions, and the lumens turning into nits is not a "simple" thing for laser TVs.
The explanation of this problem involves another major "concern" of the laser TV standard: that is, only the product set with a standard screen can be called laser TV. Otherwise, he can only be an ordinary ultra-short throw projector.
Why emphasize that laser TVs must be equipped with a good screen as standard? DapingJun believes that there are at least three important points that need to be explained: First, the same projection host and projection environment, the difference in the "contrast" effect achieved by different projection screens is a common thing - that is, a high level of optical anti-light curtain, in order to enable the laser TV to achieve a "contrast" effect that meets the quality of the picture under ambient lighting.
Second, different projection screens have a great influence on the final nit brightness. On the one hand, because the larger the screen area, the smaller the brightness of the nits - so the stream brightness of the laser TV host is required to match the area of the projection screen, at least not insufficient luminous flux. On the other hand, the "gain effect" of different projection screens is different: the gain index of the optical anti-light curtain ranges from the negative gain of 0.8 to the positive gain of 30% brightness of 1.3. For the same host stream brightness, the brightness difference between nits viewed directly in front of the screen at different gain screens can be as high as 50%.
Third, the impact of the projection screen on the viewing angle is also huge. Dapingjun feels that this may be a problem that many consumers have ignored. In practical applications, if the brightness of the projection host stream is not sufficient, a high-gain screen can be used to increase the brightness of forward viewing. However, high gain does not create more "light energy" by itself, but achieves higher positive brightness through more "focused light angles" – an operation that loses the "brightness level" of a large angle, i.e. sacrifices the angle of view. At present, the viewing angle of different optical anti-light curtains may vary from 140 degrees to 100 degrees, and the difference is still relatively large. In addition, ultra-high gain screens will also sacrifice some brightness uniformity, that is, the brightness difference between the four corners of the screen and the center position is large.
Because of the above three key performance parameters, the big screen Jun must point out that in the laser TV system, the host is only the "first half of the experience effect realization", without a reasonable "screen", there will be no "final real visual feast". Judging from the indicators of "brightness (of course, nit standard, LIQUID CRYSTAL, plasma, CRT, OLED are this standard), contrast, viewing angle, picture uniformity" selected by conventional color TVs, "laser TV standard screen" is "an inevitable rigid demand".
From projection to color TV, "the market needs re-education"
Traditional projection consumption heavy host light screen: This is the experience of the big screen Jun in the industry for nearly 20 years. But is this traditional market landscape really "healthy and correct"? The answer, of course, is no.
Indeed, from the perspective of cost, technical content, technical complexity, etc., the screen is not dry host. However, projection imaging is a "system engineering", as long as a little stuck neck, then "no matter how good the drama, it will not come out." A good screen is a crucial "core link" in the entire system. Especially to achieve color TV display effects and applications, the equipment of high-quality anti-light curtains is the "top priority"!
However, for a long time, the application of projectors adhered to the "little black room" mode. For example, the large-screen system of the cinema is the representative of the projection of the small black room - the large screen jun should point out that the screen brightness of the cinema is generally 40-80 nits. Such a low brightness If you do not strictly control the ambient light, I am afraid that the picture will really not be able to see. Similar scenes also appeared in large quantities in the early LED smart projection, as well as on all single-chip LCD projectors: this type of product has insufficient brightness output, so consumers generally use "dark" mode to watch the picture, and then develop the habit of "screen is not important".
However, in recent years, with the popularity of 2000+ brightness high-brightness projector models in the domestic market, especially the rise of special categories of laser TVs, the recognition of "screen value" has changed dramatically. Dapingjun observed that the number of brands and sales scale of optical anti-light curtain products on e-commerce platforms have expanded several times in the past three years. A "revolutionary trend" characterized by "love" screens, projection and laser TV high-quality consumption has been formed.
In summary, the laser TV industry standard pays great attention to the "application difference" between laser TV and projector products, and puts forward reasonable, scientific and extremely urgent "normative requirements" in terms of brightness indicators and screen configuration. DapingJun believes that this is not only beneficial to the development of the laser TV industry, but also to the entire home projection product market "original source", "high-quality upgrade" and its benefits. It is expected that around 2025-2026, the home projection market size will rise to 10 million units, of which one-third will be "real quality consumer products" that emphasize high-quality screens and visual brightness on screens.