Christie Digital Christie Digital

50,000 hours to 80% brightness

Getting the most from your RGB laser projector

Share

How can I use a laser projector for a longer life?

Christie

February 19, 2021

It’s no surprise that RGB laser projection is increasingly popular for cinema. A long service life and efficient power consumption offer a low total cost of ownership (TCO) that cinema owners appreciate. Laser projectors maintain stable brightness, so there’s no need to frequently adjust output power to meet brightness level, which saves time and labor costs. And with no consumables to replace, these low-maintenance all-in-one projectors save time for projectionists and technical managers. Laser projectors are quite simply the most affordable and reliable projectors in the industry.

Let’s talk about lifetime

Let’s take a closer look at the service life of RGB laser illumination, since it’s a factor that greatly affects TCO. Service life varies due to differences in electronics platforms and design optimization. With increasing market competition, the life of the light source becomes a powerful deciding factor. In order to decrease TCO and increase longevity, we focused on creating an energy-efficient projector, an integrated cooling system, industry-leading MPDs (multi-laser pack devices), and a future-proofed electronics platform.

Laser theory

Let's put aside the lively 50,000-hour question first, and instead ask what makes the operating life and brightness of the laser light source so incredibly stable?

Starting with basic theoretical knowledge, the life of laser light sources relates to two factors:

  1. Temperature
  2. The intensity of the laser drive

Temperature directly relates to the equipment’s operating environment and cooling system performance, and laser output power can be easily adjusted on the control interface of the projector.

This is key: If we can control the balance between laser operating temperature and drive power efficiently, we can reduce wear and tear on the laser and increase its operating life.

Temperature

The inside of a cinema projector showing all the fans

Large area air cooling surface

Room temperature is one of the most vital factors in laser lifetime; an optimal environment can significantly increase return on investment (ROI) for laser projectors by extending their usability. We recommend keeping Christie® Real|Laser™ cinema projectors in a room set to 25°C, the ideal temperature for laser operation. Lower is better, but not too low, otherwise condensation can form in the projector body. Air conditioning makes this requirement easy to maintain.

Keeping it cool

Another important factor is the projector's own temperature control capability, which is the cooling system. Real|Laser projectors use a comprehensive system of liquid cooling, air cooling, and precise TEC (thermoelectric cooler) temperature control. The LOS (Laser Optical System) and optical engine are subjected to overall circulation heat treatment to obtain efficient cooling. We design models with less than 30,000 lumens as all-in-one chassis with internal circulation. We equip models with more than 40,000 lumens, like our CP4440-RGB and CP4450-RGB, with external water-cooling boxes for efficient heat dissipation through the active refrigeration cycle.

In addition to the hardware contribution, Real|Laser's software uniquely correlates laser output power with ambient temperature through patented LiteLOC technology. If ambient temperature in the equipment room is too high, the optical output power automatically reduces the operating settings of the laser light source to prevent overloading it.

Laser drive intensity

Laser drive intensity is a more complicated factor. Let us simply express this concept in terms of output power. In fact, for a projector that uses different light source output power, the laser attenuation rate is also different. In simple terms, with higher power daily operation, there’s a quicker rate of decay. For example, in a room temperature environment of 25°C, if we always operate Real|Laser projectors at 100% power, after 30,000 hours, its brightness will be reduced to 80% of the initial maximum brightness. (Note that this is only for Christie’s Real|Laser RGB pure laser projectors, thanks in part to our MPDs. Other brands and phosphor laser platforms have not yet accomplished this.)

The golden ratio

However, if we operate at 80% instead of 100%, brightness decay decreases to just 80% after 50,000 hours. Even slightly reducing laser drive intensity greatly increases the projector’s service lifetime, and the quality remains consistent. And if we continue to reduce daily operating power, the projector’s lifespan continues to extend.

The following diagram gives us an intuitive understanding of how reducing brightness leads to longer laser lifetime.

X-Y axis chart showing the effect on brightness over the course of operating hours

Always leave some margin

When you choose equipment for a new theater, keep these factors in mind: configuring the most reasonable projector brightness according to screen size and 3D system performance, how much output power is used in daily projection work, and the lifetime of the ideal machine. The concept of "always leave some margin" stands as a golden rule for projectors.

A note about RGB

It’s worth noting that the attenuation rate of red, green, and blue lasers are not the same. Christie’s LiteLOC technology helps maintain accurate colors by automatically sensing the light output and adjusting the laser drive power to maintain a constant light output, which fixes white point accuracy and prevents color cast.

What do we mean by ‘laser life’?

As we have shown above, Christie Real|Laser projectors operated at an ambient temperature of 25°C maintain 80% brightness output for 50,000 hours. But do we simply define this lifespan as 50,000 hours? Not at all. After 50,000 hours, even though it can’t meet 100% brightness, your Real|Laser projector still meets DCI standards. As another example, the brightness of a Christie CP4440-RGB is 45,000 lumens, which means that even at 70% output power, it still produces more than 30,000 lumens and still shows high-quality images on large screens.

In summary, Christie Real|Laser projectors rely on advanced MPDs , efficient cooling and heat dissipation systems, LiteLOC™ software for precise control, and other key engineering functions to deliver the longest laser lifetime in the market. Keeping a Real|Laser projector under 80% output power intensity means it can continue at 80% brightness for 50,000 hours—and beyond.

Related products