Sustainable Technology: Reducing Power Consumption of Projectors

(Based on the article: Reducing Cinema Projectors Power Consumption Using Global Dimming and Image Statistics)

Cinema projectors have greatly improved in recent years, especially with the transition from film to digital. Image quality, distribution, operability, and cost of ownership have improved the most in the last 20 years. However, energy consumption still remains a major issue, especially in movie theaters. Thus, the question arises: What techniques can be used to reduce projector energy consumption?

A recent study performed by engineers from Barco and MTT examined a strategy called Global Dimming, a technology that varies the total light output level of a display. Unlike manual dimming, Global Dimming is dynamic and can be employed dynamically without user input. There are several different ways Global Dimming can be implemented on a projector. However, this study focused on a specific method utilizing four separate steps: dimming mechanisms, dimming decision algorithms, dimming predictions, and dimming modulation algorithms.

The study used five films from four different genres (drama, action, war, and crime) to determine how much power could be saved while maintaining the quality of the content. The results?

If the images in the film remained unaltered, power consumption on the projector was reduced by approximately 20%. The reduction in power consumption could be reduced by nearly 60% if images are altered. This, unfortunately, comes at the cost of reduced image quality. However, combining Global Dimming with HDR Lightsteering projectors (which Barco produces) could dramatically reduce power consumption while maintaining the image quality of a movie.

As the experiment was only done with five movies, more testing is needed to ensure this method can be replicated and results in more efficient projectors. That said, the results of this test are very promising and are a bright spot for projection technology. As more testing occurs, more technologies will emerge that keep projectors efficient and movies looking beautiful.