LiDAR Space

The diode-pumped alkali laser (DPAL) is a gas laser pumped by diodes. It leaves only a few percent of each pump photon behind as heat. It has no solid medium to distort under load, and its flowing gas carries the heat away. It emits in the near infrared, where the atmosphere is clear and a director of a given size forms a smaller spot than at one micron. That combination is why the idea has drawn two decades of effort.

What has held it back is the pump. Laser diodes are about a thousand times wider in wavelength than the atoms they must excite, and the customary remedy, high pressure and high temperature, gives back much of the advantage. And because the atoms cannot store energy, alkali lasers have been continuous-wave machines.

LiDAR Space has taken these obstacles in turn. A patented atomic-line-filter cavity locks the pump to the alkali line, which lets the laser run at low pressure. A ring resonator exposes its low-power return path for mode control. A folded multipass path stores energy in the circulating pulse. And burst pumping, which the instant atomic lock makes possible, raises the peak brightness. The result is a low-pressure, pulsed DPAL.

The technology serves two missions, both power-scalable: solar-suppressed sensing, applied first to detecting and tracking small objects in low Earth orbit in daylight, and ablative effects delivery, applied first to countering uncrewed aircraft. Both apply on land, at sea, in the air, and in space.

The company is based in Durham, New Hampshire, is a member of the Joint Directed Energy Consortium, and is eligible for SBIR Phase III awards.