The LISA laser subsystem is built around fiber-coupled, monolithic, solid-state lasers. These common infrared lasers, operating at a wavelength of 1.064microns are naturally compact, reliable, power-efficient and readily stabilized. The laser subsystem includes a laser, an optical isolator, and electro-optic modulator and a fiber coupler. There is one laser subsystem and one spare for each optical assembly, mounted on a heat sink with active thermal control.
Color key: fused silica spacer (gray), laser diodes, Nd:YAG crystal (dark purple)
From LISA TRIP Review (2002) (Fig D-11)