3. Operating Procedure

High power laser diodes have a distinctive structure compared to semiconductor lasers for optical discs or laser beam printers. This is because the laser beam is emitted from a line-shaped portion only a few hundred microns wide in contrast to other semiconductor lasers which are considered to be point light sources a few microns in size (Fig. 1).

In addition, array lasers have these linear light sources arranged side by side at a pitch of several hundred microns (Fig. 2). The length of these linear light sources is called "emitting line width".

This structure gives the NFP and FFP characteristics different shapes in the horizontal and vertical directions of the active layer (Fig. 3). In particular, the horizontal NFP shape for the SLD330 series is close to a trapezoid shape, although some strength distribution remains.

SHP packages include the φ9 mm V-PKG and the YT-PKG with on-chip TE cooler (Peltier element). Array type packages include the open heat sink type S-PKG and the water cooled type S3 and S4 packages (Fig. 4).

Cooling methods suited to the above SHP packages are required, and these are shown on the following page.