No need to dim the lights with new Hitachi projectors
By Tim Hornyak
Hitachi has developed projector technology that makes video display clearly in brightly lit rooms.
The processing hardware is just under 2 square centimeters. That means the technology itself could help enhance video in everything from security cameras and vehicle camera systems to pocket projectors and home theater systems.
The technology improves the visibility of the projected images without using more light, Hitachi said, adding that it will be incorporated in projectors launching in the U.S. and Europe in April.
Hitachi’s approach focuses on video processing. Instead of processing the entire image as a whole, it analyses individual characteristics and enhances whatever is necessary.
“Most manufacturers simply increase the power source for the light projection to improve visibility,” said Masayuki Yoshida, spokesman at the company’s R&D headquarters. “Hitachi’s technology does not change the power of the light, but it won’t make dark regions of an image completely black or lighter regions washed out.”
Hitachi researchers developed an algorithm that is based on a model of how the human eye and brain perceive colors and light known as the Retinex Theory. It processes brightness, resolution, and color composition and makes individual adjustments for each.
The results include the enhancement of dark areas in a video without affecting brighter ones, and object outlines are better defined so they appear more distinctly.
The researchers also optimized the algorithm’s processing sequence so it could be efficient enough for commercial applications. They developed compact logic circuits that can perform real-time processing at 60 frames per second for still images and 1920 x 1200 pixel high-resolution video.
Hitachi Maxell will launch seven projector models with the enhancement technology in Europe and the U.S. They will have lumen ratings of 2,700 to 3600 and two HDMI digital inputs.
“In recent years, the performance of various display devices has been improved, but it is not sufficient in comparison with the dynamic range of the human eye yet,” said Hitachi spokesperson Tomoko Sato.
“Therefore, visibility enhancement by image compensation has been very desirable. In order to support such needs, Hitachi has developed this technology,” he added.