A well-known LED/laser hybrid is the Panasonic PT-RW330 laser projector. In this case, the red light is generated by one or more LEDs, as these are cheaper to manufacture and provide sufficient light output compared to red lasers. The blue and green part of the color spectrum is achieved by blue lasers and a phosphor wheel.
RGB laser projectors are the current high-end class and should be seen as the technology of the future. Here the production costs must still decrease to offer these devices for the mainstream market. These laser projectors consist of three different types of lasers (red, green and blue) which then generate the required white light. The projectors from Christie and Barco are particularly worth mentioning here (e.g.
Christie D4K40-RGB and Christie Roadie 4K40-RGB).
Laser projectors, no matter what type, have various advantages. In the past, xenon lamps had to be replaced after a good 800 operating hours, while mercury-based UHP lamps had to be replaced after about 2,000 running hours. Now, manufacturers of current laser projectors promise a life expectancy of 20,000 operating hours with a maximum brightness reduction of only 25%. However, since the technology is still too new and therefore no long-term tests exist, we cannot confirm this beyond doubt at the moment. The first devices with 20,000 hours have already been in our hands and mostly these
projectors were still very convincing. Another advantage is the fast cooling time after switching off the laser projector. So now there is no need to wait for several minutes, but the dismantling can start after a few seconds.
Laser light sources are better for the environment. Both use and disposal are less harmful to the environment compared to xenon and UHP lamps. Also, although the production of laser units is more expensive at the moment, it is more environmentally friendly to implement. In addition, laser projectors consume somewhat less power for the same output, which of course also has a positive effect on the environment.
As far as projection quality is concerned, laser light sources have both advantages and disadvantages: full light output is achieved after just a few seconds, but at the same time the light is usually perceived as rather cold and artificial (especially in direct comparison with
xenon projectors, which project a very wide light spectrum). Due to the very focused color space of the laser light source, which, for example, do completely without infrared light, significantly less heat is generated, which means that the laser projectors also require less cooling. This means that smaller and, above all, quieter fans can be installed, which has a positive effect on the noise level of the projectors. Thus, every director is happy when
theater projectors no longer need a projection room so that the audience can understand the actors.
Laser projectors also tend to be easier to install because the lower cooling requirements mean that the projector can be hung or positioned in any direction (portrait mode or downward) (360° capable). In the past, the A/V installer needed special lamps to set up the
Panasonic PT-DZ21K in portrait mode, for example, so that they could be cooled properly.
At the moment, the acquisition costs for laser projectors are quite high compared to classic lamp projectors. Thus a purchase is worthwhile purely arithmetically only if the laser projector runs for at least 12 months each day 8 hours. The ReBeam GmbH has meanwhile access however also to
used laser projectors, which offer a large price advantage in relation to
new devices. A disadvantage, which will hopefully be solved soon, is that at the moment there is no possibility to change the laser light sources, if the laser should fail or the 20.000 working hours are reached. Actually, almost all projectors are designed for a much longer lifetime. So this disadvantage is currently still an artificial shortening of the life cycle. It remains to be seen if and when manufacturers will react to this, or if they will find other companies to take on this challenge.