Mitsubishi Electric Improves Color Gamut of Laser Display by 70%

Oct 22, 2015
Naoki Tanaka
A 50-inch 4k LCD display using the new RGB laser backlight unit (right) and a 4k LCD display using a conventional technology (left)
[Click to enlarge image]

Mitsubishi Electric Corp showed a laser display whose color gamut is about 70% wider than that of the company's existing laser displays.

In addition to the new laser display, the company's laser backlight technology used for the display was exhibited at Ceatec Japan 2015, which took place from Oct 7 to 10, 2015, in Chiba Prefecture, Japan. With the new technology, it becomes possible to cover 98% of the color gamut of BT.2020 (a standard for 8k video).

In the past, Mitsubishi Electric developed a backlight unit using a red laser diode as a light source and demonstrated an LCD display equipped with the unit. The backlight technology that the company showed this time uses laser diodes not only for the red light source but also for the blue and green light sources.

Moreover, the company realized the wide color gamut by designing a color filter whose properties are suited for RGB (red, green and blue) laser light sources.

In general, laser light goes in a straight line. To use it for the backlight of an LCD panel, the light needs to be spread in a planar direction. Therefore, Mitsubishi Electric developed a bar-like light guide plate containing a material that scatters light. With this plate, the company succeeded in spreading laser light in a planar direction.

However, the high prices of laser diodes are a challenge in commercializing the new laser display. At this point, the cost is much higher than that of the LED backlight units of normal LCD TVs, Mitsubishi Electric said. So, the company is not considering using the new display for consumer applications. It aims to have the new display employed for business-use displays that show 8k wide-gamut video at broadcasting stations, etc.