11 November 2010


Mitsubishi samples record-output 1W red laser for pico projectors

Tokyo-based Mitsubishi Electric Corp says that on 18 November it will begin sample shipments of its new ML501P73 red laser diode (LD), which has what is reckoned to be record pulsed output power of 1W for the 638nm wavelength band, suiting pico projectors and other portable display systems that require a high-brightness red light source.

Pico projectors have attracted much attention because they can be embedded in or connected to mobile systems such as cellular phones and laptop computers. Laser diodes are widely used as the light source because they can project a wider range of colors compared with lamp-based projectors. Compared with LEDs, laser diodes deliver higher output while consuming less power, extending battery life. They also enable focus-free operation, because optical systems with great depth of field can be used with laser beams.

After only in January 2009 launching a 638nm laser with what was then record output of 110mW (operating in continuous-wave mode), the firm boosted output to 300mW in July 2009 then 500mW in January 2010, helping it to achieve luminosity of up to 60 lumens (lm) compared with just 10lm in LED-based projectors.

However, at high temperatures, the output power of red LDs with wavelengths shorter than 640nm was insufficient for high-brightness projector applications. Mitsubishi Electric says that it has now used its capabilities in applying window mirror structures and epitaxial growth technology to develop output power of 1W at the 638nm lasing wavelength, doubling luminosity to more than 120lm for pico projectors.

Supplied in a standard 5.6mm-diameter CAN package, the ML501P73 can be operated over a temperature range of –5ºC to +40ºC while emitting at an output power 0.5W in continuous wave (cw) mode and 1W in pulsed mode at a duty ratio of less than 33% and a frequency of 50Hz or higher. At a CW output of 500mW at 25ºC, operating current is 660mA and operating voltage is 2.2V. The threshold current is 170mA.

In addition, at a case temperature of 25ºC, the new laser has an what is claimed to be an industry-leading electrical conversion ratio of 32% at 1W (compared with 32% for the 500mW-output laser), helping to reduce power consumption in pico projectors.

See related items:

Mitsubishi launches record 500mW red laser for pico projectors

Search: Mitsubishi Red laser Pico projectors


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