New collimating lens systems for laser diode package

Abstract

The design of a new collimating lens system for a laser diode package for optical communication is discussed. This collimating lens system achieves enough space between the laser chip and the lens, with the beam diameter smaller than the effective diameter of the isolator. This system consists of two lenses. For beam angle deviations caused by misalignments of the laser diode and the lens system, the relationships between the beam diameter and the beam angle deviation ratios are the same as those of the conventional lens system. It is demonstrated that making the beam diameter small decreases the beam angle deviation ratios. This result is useful for designing a laser diode package.<>