Matsushita today announced that it has developed the world's first high power, high efficiency SHG blue laser ready for use in next-generation optical disc recording systems. This development will be announced at ISOM2001, the International Symposium on Optical Memory, on October 19 in Taipei, Taiwan. Working samples will also be on display at the Panasonic booth at CEATEC JAPAN 2001, to be held from October 2 to 6 at Makuhari Messe (Nippon Convention Center) in Chiba, east of Tokyo.
As DVD and other high-density storage media become more widespread, blue lasers have gained increasing importance for their minimized focusing spot, necessary to realize the data densities required of the new media. The company first announced the development of an SHG blue laser in February 1999 and has been continuing its development. Panasonic's new blue laser achieves a high power level of 30 mW, 15 times stronger than previous SHG lasers, whose 2 mW has not been strong enough for disc recording. Moreover, the new blue laser produces a wavelength of 410 nm, shorter than previous blue lasers' 425 nm, considered too long for next-generation optical disc systems. The higher power and shorter wavelength were made possible by using a high-powered wavelength-tunable infrared laser diode and then transforming the infrared light into blue laser light.
By using a high efficiency SHG device (in collaboration with NGK Insulators, Ltd.), the size of the newly developed blue laser has also been greatly compacted to just 0.3 cc, only one-fourth the size of previous packages. And by employing a high precision assembly technique for miniaturized SHG lasers, this new laser also achieves one-third the noise level and 90% reduction in wavelength variation compared with GaN (gallium nitride) laser diodes.
SHG: Second harmonic generation light source. A source of light generated by using an SHG device to split the wavelength of semiconductor light into two distinct wavelengths. For example, a 425 nm blue laser light is achieved by using an SHG device to split the 850 nm wavelength light of an infrared semiconductor laser diode.