Since the invention of video projectors, they have always had a problem with the light source; it is difficult to combine high brightness with natural color reproduction. The introduction of the so-called laser-phosphorus modules solved this problem only for one class of projectors – expensive models for recreation centers. In relatively cheap home and office models, this only gave an increase in brightness with a longer “life” of modules without replacement, as opposed to lamps, and there was practically no improvement in color rendering.
Therefore, research in the field of creating alternative light sources is actively continuing. In particular, recently the Chinese company XGIMI, whose projectors, presented its original module. They called the development very banal – Dual Light Technology, because it uses two types of light sources: LEDs and lasers. I must say that this combination is not the first time: ten years ago, Casio released a projector with a laser and diodes, but the laser in it did not shine directly, but through a phosphor, as in laser-phosphor modules.
The fact is that diodes and lasers differ by orders of magnitude in energy output, and the phosphors of diodes are comparable to those in laser modules. At the same time, the use of just three diodes gives a full-color image with a wide palette, but low brightness, and three lasers – bright, but an unnatural image with artifacts is obtained, because the spectrum of any laser is extremely narrow and actually consists of one wavelength.
At XGIMI, both diodes and lasers are used without phosphors and phosphors – they shine directly, and their light is summed using a special optical system. In total, this module has three LEDs (R, G and B) and two lasers – blue and red. And the relative alignment of the characteristics occurs due to the introduction of a special component in the optical system, developed with the participation of the petrochemical holding Zeon Group from Düsseldorf.
What the use of such a module with five light sources ultimately gives, XGIMI has not yet reported – it does not give either the color gamut area or the resulting luminous flux. And the timing of the appearance of the first models with Dual Light Technology is also, although the company has already managed to receive certificates from regulatory European authorities like TÜV Süd.