NDR is in uniquely positioned to pioneer in vertical cavity surface-emitting laser (VCSEL) based optical pick-up heads for data storage applications. In collaboration with leading CD driver makers, we are developing a wide variety of pick-up heads, including monolithic, multi-track, CD/DVD, MD and CD/DVD-RW. Unlike any conventional designs, our pick-up devices integrate multiple micro-lasers and photodetectors on a single chip to read and/or write multiple data tracks, enhancing performance while reducing production cost. As an added advantage, the pick-up heads can be easily integrated with PDIC and other components. With multi-track reading and writing, data transfer rate will no longer be limited by rotational speed of the disk, but comparable to that of hard disk drives.

      Some 800 million optical heads are in use today, roughly 50 % of them in audio CD players. For audio CDs and car stereos alone, the demand for low cost, thin-type monolithic pick-up ICs far outstrips supply. Global demand for optical CD, DVD and CDRW heads will amount to 119.9 million in 2002. As multi-media and Internet are becoming household staples, the market for DVD, CDR and other optical drives will increase dramatically. The projected 10% annual growth rate of the optical hard-drive industry will further expand the market for our optical head products as the new millennium unfolds. We aim to become the market and technology leader in the development and supply of low-cost, high-performance monolithic optical pick-up heads for optical data storage drives.

Characteristics

  • Integrated chip containing arrays of micro-lasers (VCSELs) and photodiodes (PDs)
  • Simultaneous reading of multiple tracks using multiple VCSELs and PDs in place of a single laser-detector pair to increase data transfer rate
  • Fast electronic servo using groups of VCSELs and PDs to correct optial magnification errors
  • Optimal element layout on the chip to achieve high performance and compact size
  • Optical scheme providing small deflections of reflected light to reach photodiodes