The 3D light efficiency of the laser projector can reach 45-XY Screens-img

The 3D light efficiency of the laser projector can reach 45%

by:XY Screens     2021-08-28
Recently, there have been more and more discussions about high-brightness laser projectors. It seems that laser projection will soon become the future trend of digital cinema, and I have always been skeptical. It needs to be admitted that the color gamut of the laser light source is wider, which will bring about the improvement of picture quality and color, but the cost performance is really low. Because the 60,000 lumens laser projector only doubles the brightness of the traditional 30,000 lumens xenon light source projector, and the price is much more expensive. In particular, I heard that a company gave the brightness index of a 6 million 6P lumens laser projector: in a 24m wide white screen (1.8 gain), only 7fL 3D screen brightness (estimated light efficiency is 22%) can be obtained, which is quite regrettable. Because a traditional 30,000 lumens projector is equipped with light recyclable 3D, the front brightness of the screen on the metal screen can reach this brightness (of course, the uniformity is flawed). Later, I heard that another company gave a 6P lumen laser projector with a built-in 3D light effect of 45%, that is, a 24m wide white screen (1.8 gain) can get a 14fL 3D screen brightness. I was really surprised, because This means that a 30,000 lumens laser projector can obtain 7FL 3D brightness under the same conditions. It is also a well-known company in the industry. With the same laser module configuration, one uses a single projection head and the other uses a dual projection head. It is impossible to have such a big difference. According to the analysis, in the single-head mode, 30,000 lumens are provided to the left eye 3D image, and the other 30,000 lumens are provided to the right eye 3D image. Because the image projected to the left and right eyes is refreshed intermittently, that is, the viewer sees the image with the left eye. , The right eye cannot see the picture, and vice versa, so the overall perceived brightness is 30,000×22%u003d6600 lumens; while in the dual-head mode, 30,000 lumens are provided to the left eye 3D image, and the other 30,000 lumens are provided to the right eye 3D images, but the images projected to the left and right eyes are refreshed at the same time. The left and right eyes of the audience can see the left and right eyes at the same time, so the overall perceived brightness is 30,000×22%×2u003d13200 lumens, which is exactly twice the former. It is said that another tall Max company also adopts a dual-head model, which is to be tested. But there are still doubts: in fact, dual-camera polarization 3D is very common in theaters. Two 30,000 lumens projectors are equipped with dual-camera polarizers. The left and right eyes of the audience can also see the left and right eyes at the same time, but the overall light effect is only 16 % (Same as passive 3D light effect), how come the laser era has increased the light effect by 45% to a terrifying height? As a technical control, after digging into the traditional two-machine polarization and color separation 3D methods, the problem came out. 3D principle: Traditional two-machine polarization method: two polarizers are polarized, and the light projected by the left and right machines is separated by the left and right polarizers. Two orthogonally polarized lights are formed by filtering to ensure that the images received by the audience are not disturbed. However, in principle, 50% of the light has been lost. Considering the loss of about 68% of polarized glass and glasses, the total light effect is (1-50%)×(1-68%)u003d16%. The laser color separation technology is different. It does not need to use a color wheel to separate colors (the light loss is large), but creates two sets of RGB light with different wavelengths from the laser mode. The left and right glasses of the 3D dichroic glasses accept different For wavelengths of light, the light loss of the glasses is 55%, and the comprehensive light efficiency is 1-55%u003d45%. This calculation is more reasonable. According to this 45% light efficiency, I feel that the commercial prospects of lasers are still promising, because the theater itself can calculate the account and find that the laser projectors are more cost-effective: In order to achieve the 7FL 3D center brightness, a 24-meter-wide metal screen + The total cost of the traditional dual-machine 4K (30,000 lumens) + server is about 1.6 million, 100 xenon lamps used in ten years, the cost is 1.1 million, and the total is 2.7 million; in particular, only in the initial stage of use, the center of the screen can reach 7FL 3D brightness , The edge is estimated to only reach 3FL; the xenon lamp has attenuation in the later stage of use, and it can only reach about 4fl 3D in the center of the screen. In order to achieve the same 3D brightness, a 24m wide white screen + 30,000 lumens laser projector 4K (dual head) + server, 2.7 million should be enough, considering that the laser has no attenuation, the white screen has good uniformity, and the overall 3D brightness can be maintained. The cost-effective advantage of laser projectors is obvious. Well, it seems that it is possible for the laser projector to achieve 45% luminous efficiency. I hope that one set can be actually tested in the theater.
Custom message
Chat Online 编辑模式下无法使用
Chat Online inputting...